Navitron Renewable Energy and Sustainability Forum

General Renewable Topics => Off-Topic => Topic started by: Heinz on November 11, 2010, 12:46:59 PM



Title: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 11, 2010, 12:46:59 PM
Oh god, he's going to kill us all.... Despite the the woman's cry of doom, we are still alive as is the fridge  ;D
couple of days ago the fridge stopped cutting out, ran all the time and didn't cool much. I hate chucking out stuff which is 90% perfect just because one part has failed, seems to be my "calling" to repair machines which others would class as unrepairable or not worth the time.
A modern fridge has no valve for re gassing as the fill pipe is crimped shut in the factory.
I had noticed ages ago in the BES plumbing cat. that the commercial refidgeration fill valves are just shrader tyre valves.  Also I knew from researching ground source heat pumps that propane was a good refidgerant. So despite the womans complaints "why waste time on an old fridge"  and "you'll blow us all up" I took the fridge out to the workshop. Carefully cut off the crimped fill pipe, nothing came out so the gas was gone and my diagnosis was correct.
(http://www.goatpark.force9.co.uk/assorted/fridge01.jpg)
I got a tyre valve and shaved the rubber off it with a knife, then sanded it clean. sleeved the copper fill pipe to the tyre valve with a bit of 8?mm copper pipe and soft soldered them together.
(http://www.goatpark.force9.co.uk/assorted/fridge02.jpg)
Screwed in the core and pressurized it with propane, 60psi. I used a propane cylinder with unregulated fitting and the tyre valve connector robbed off my vintage Dunlop footpump. Checked the plumbing for leaks but could find nothing, even cut out a chunk of the insulation so I could check the joint where the high pressure pipe connects to the expansion section. No leaks anywhere that I can find with the soapy water so I can only assume that the leak is VERY small and it may have taken the ten years since we bought the fridge for the gas to leak out. If I have to top it up in another ten years I'll be happy  :D
I emptied the system again and with the aid of a stick, whiskey, digital scales and a chair refilled it with a measured amount of propane.
(http://www.goatpark.force9.co.uk/assorted/fridge04.jpg)
 The sticker says it should have 24g +- 1g for R600a so I put a smidgen more than this in, bound to lose a wee bit in the pipe and disconnecting the valve. If you just connect the propane cylinder to the fill pipe, only a small amount of gas will flow to the fridge, but as the fill pipe is on the suction side of the compressor, switching on the fridge will suck the propane in  ;D
The fridge now cools very quickly although the thermostat is faulty, even with the end of it covered in ice, still doesn't turn off, Ebay 3.70 for a new one  ;D

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Justme on November 11, 2010, 12:56:32 PM
Using that lever method to weight the gas will give the wrong amount as half the weight is on the chair.
Unless you took that into account.


Oh whilst the gas is very similar you also need some lube oil in the fridge.
It might still be in there from the old gas & it might not.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 11, 2010, 01:04:20 PM
Using that lever method to weight the gas will give the wrong amount as half the weight is on the chair.
Unless you took that into account.


Oh whilst the gas is very similar you also need some lube oil in the fridge.
It might still be in there from the old gas & it might not.

The weight was too much for the wee scales, which is why I used the stick and put in 15g of gas which is really 30g.

Hadn't considered that it may be low on oil, but would have thought that if the oil had escaped, the leak would be A/ oily and B/ big enough to find???
Cheers,

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: dhaslam on November 11, 2010, 01:34:44 PM
But if the gas escaped before what is going to be different now?


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 11, 2010, 01:46:37 PM
But if the gas escaped before what is going to be different now?

Well, I kind of agree, but having failed to find any leakage I think the leak must be very, very small and if it's taken ten years to leak out, then maybe it'll take another ten years to leak out again??? Time will tell... and nothing lost but a couple of hours and a smidgen of propane if it doesn't last. Better to try that than add it to the scrap pile. There's a MOUNTAIN of fridges beside the Perth road, can't remember the road number, but you cross this enormous bridge and look down to see piles and piles of dead fridges. I'd rather avoid adding to that if I can...
Cheers,

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Countrypaul on November 11, 2010, 01:56:26 PM
If you can't find the leak in the piece that is left, maybe it was in the piece you discarded - ie. the crimp could have been leaky.

Maybe this is a hopelessly optimistic view, but then again someone has to be, and it may reassure SWMBO.

Paul


Title: Re: Fridge, you'll kill us all.... :o)
Post by: solarcycle on November 11, 2010, 03:14:52 PM
That fridge mountain is below the Friarton bridge on the A90 to Dundee, its enormous and getting bigger no doubt!


Title: Re: Fridge, you'll kill us all.... :o)
Post by: biff on November 11, 2010, 03:15:17 PM
hello heinz,
       i have to say that it looks a bit risky,the propane might leak out and collect in a pool or cloud and maybe during the xmas party go bang,to experiment is great but you have to live with it,( god this is strange coming from me),
     reminds me of a friend,,or kind of a friend who bought a strimmer at the bootfair bout 20yrs ago,the strimmer was running fine but the actual cutting effort was missing,so he bodged a 9" black and decker circular steel disc onto the end with a bolt ,nut and big washer,,,no guard,so he started it up and it began to shake so he gave it the gas and it began to steady up,then the nut and washer fell out on the floor and this thing is doing 90 a few ft from him in his enclosed workshop, the door was closed,and he needed his two hands to hold it steady.he could not ease of the throttle because the vibration would come back,finally he lost his nerve and threw it across the workshop,diving to go out the door, the disc passed inches from his face between him and the half open door,slicing a great chunk out of the door,it then continued to rocket around the inside of the workshop taking chunks out of everything it came in contact with,
    i drove up in my van as he staggered out the door,he was shaking from head to foot and crying,i could not believe the damage ,some cuts were neat and some looked like a target practise.,the disc even took the plaster of the wall in places. and the disc itself,,,,well next to no wear. and himself,?, no damage but badly shaken.
    the moral of the story?? well there are some things you are better to buy new,
 :hysteria                                 biff


Title: Re: Fridge, you'll kill us all.... :o)
Post by: rhys on November 11, 2010, 03:34:45 PM
Hm and this fridge won't be A++ rated wil it? svengo


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 11, 2010, 04:09:55 PM
hello heinz,
       i have to say that it looks a bit risky,the propane might leak out and collect in a pool or cloud and maybe during the xmas party go bang,to experiment is great but you have to live with it,( god this is strange coming from me),

I did consider this, but as there are now thousands of fridges made with propane as the refrigerant each year and the amount is so small, I decided it would be fine. I have no way of measuring it, but if my other half is slow to ignite the gas ring on the cooker or one of the kids plays with the cooker controls, how much gas is released into the kitchen??? I did find some rules and regs. bumf on the net which said that the max permitted quantity of propane in a domestic fridge was 150g, presumably to keep the volume low enough to prevent an explosive mix being formed if released into the air contained in an average sized kitchen. 24 to 30g is Heinz-all and if it does leak, it'll be over days/weeks/years, not just released in one "lump". It'll be fine  ;D

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Philip R on November 11, 2010, 04:16:36 PM
I like your experimentation with the propane gas.  stir:

I notice the compressor has an R600a label on it, R600a is isobutane. Maybe some butane would have been a better match for your system. To late now as it seems to be working.

It would seem that propane is fairly compatible with the lube oil used in the older R12 and R22 systems. I have the former still in my kitchen fridge, will one day by a nice A++ device, see the savings and wish I had replaced it sooner!!


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Philip R on November 11, 2010, 04:19:22 PM
Apologies for my bad spellings in the previous write up. I used the spell checker but pressed "ignore" instead of  "change". wacko


Title: Re: Fridge, you'll kill us all.... :o)
Post by: johnrae on November 11, 2010, 06:20:30 PM
Great thinking and nice work on the fridge.  Sensible application of inovation and common sense.

As for the guy with the strimmer - a clear candidate for the Darwinian award.  When you put what is effectively an unguarded circular saw on the end of a piece of garden equipment ---------

jack


Title: Re: Fridge, you'll kill us all.... :o)
Post by: wookey on November 11, 2010, 06:25:56 PM
World-class bodgery. Well done. Interesting to know if efficiency changes significantly. Do you know how much it used before?


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Amy on November 11, 2010, 06:46:27 PM
Great bodgeneering mate, but next time, please do it out doors.

Gas explosions take no prisoners.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: pontiff on November 11, 2010, 09:10:57 PM
hello heinz,
       i have to say that it looks a bit risky,the propane might leak out and collect in a pool or cloud and maybe during the xmas party go bang,to experiment is great but you have to live with it,( god this is strange coming from me),

 24 to 30g is Heinz-all and if it does leak, it'll be over days/weeks/years, not just released in one "lump". It'll be fine  ;D

Heinz

30g of propane occupies about 16 litres at room temp and pressure. The lower explosive limit for propane/air mix is 2.1%. You would only reach this if your kitchen was under 760 litres air volume. Unless you are a hobbit you should be ok even if it all leaks at once. Very impressive work!

Please bear in mind this is advice from a man who once connected an outdoor garden tap to a gas pipe by mistake.  ::)



Title: Re: Fridge, you'll kill us all.... :o)
Post by: mespilus on November 11, 2010, 09:32:34 PM
I seem to remember a post from a forum member who had many
kW of cooling in his commercial premises.

He stated something along the lines of
'that all fridges leak, just slowly, and are 'overfilled'
at the factory to give a reasonable expected lifespan.

As the volume of refrigerant gas decreases,
the fridge just runs the compressor more frequently'.

Apologies to the original poster, for forgetting his/her name,
and for any paraphrasing.

Well done in resuscitating your 'dead' fridge.

I suspect the pile of fridges is awaiting an upturn
in Chinese steel production, before the refrigerant gas
reclamation units which chew up old UK fridges return to
economic operation.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 11, 2010, 11:05:12 PM
World-class bodgery. Well done. Interesting to know if efficiency changes significantly. Do you know how much it used before?

Thanks. No idea what it used before. I keep meaning to buy one of those plug in energy usage meter do-da's but there's always something more important to spend my spare fivers on...
Cheers,

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 11, 2010, 11:12:19 PM

30g of propane occupies about 16 litres at room temp and pressure. The lower explosive limit for propane/air mix is 2.1%. You would only reach this if your kitchen was under 760 litres air volume. Unless you are a hobbit you should be ok even if it all leaks at once. Very impressive work!

Please bear in mind this is advice from a man who once connected an outdoor garden tap to a gas pipe by mistake.

Thanks, useful info to fend off the wrath of SWMBO  :)

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 14, 2010, 09:53:29 PM
Update,
Got the new thermostat and fitted it but still didn't seem to work properly. Fridge not getting as cold as I'd like so drained the propane (outside) and refilled with butane which someone here had suggested. Now cools better and the condenser (black radiator thingy at the rear) doesn't get as warm, about 10deg C lower than on propane, so I assume it's more efficient?
(http://www.goatpark.force9.co.uk/assorted/fridge06.jpg)
Yes, that is a bicycle pump connector with one end chopped off and I did fill it in the kitchen again, sorry Amy  whistle . Much easier to fill it with the wee can of camping cooker butane than it was with the propane.
What temp is a fridge supposed to be at?? A Google says 3 to 5deg C but where in the fridge? The rear wall is at -18 (running) where the evaporator coil is with ice crystals forming, the milk in the door is at 6deg C and the glass of water on the middle shelf is at 4 to5 deg C, bacon on the bottom shelf at 2deg C. I wish I'd had the foresight to measure the temps a month ago when it was hunky-dory... Will need to start carrying a temp gauge and measure fridge temps wherever I go  ::)
Cheers,

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: climber on November 14, 2010, 10:31:56 PM
Excellent! It always annoys me when I see fridges being scrapped.

Must stop by the scrappy under the Friarton bridge and see how many fridges I can revive.........


Title: Re: Fridge, you'll kill us all.... :o)
Post by: roscoe on November 14, 2010, 11:03:12 PM
Absolutely magic, double applaud  :)

I think we have a white goods E-Room on the go, love it.

Side sound bite...
Once had a fancy new german car AC stop working, the garage with a straight face said whilst the AC system was under warranty, the refridgerant gas was not!
The buggers wanted several hundred to re-gas and if no leak found then not covered under warranty... disbelief.
At the time a wee van man recharged the system for fifty and did a leak test at my house, amazed it was soooooo simple.

Surely some clever/determined people could manage to uprate (energy rate) all these un-loved fridge mountains people talk about.

Which brings me finally onto the question ?

Any tips for improving the efficiency of an old cooling appliance ?



Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 14, 2010, 11:53:12 PM

Which brings me finally onto the question ?

Any tips for improving the efficiency of an old cooling appliance ?

Well, as I'm in "fridge mode" at the moment, I've been thinking about this. Seems to me that more insulation round the outside would help. If I still lived alone, I'd just glue some foam sheet all over it, but SWMBO will never pass that one... The other thing is the condenser round the back. It's warm/hot and it's just an inch away from the part you want to be cold... chocpot: seems to me that spacing the condenser another inch away and adding a sheet of something to reflect the heat would help.
Back of fridge - SPACE - reflector - SPACE - condenser.
I had wondered about something cheap like hardboard? Foil covered on one side?

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: knighty on November 14, 2010, 11:57:30 PM
iirc.... you can buy a can of fridge gas about the same size as your butane can there which is ready made to re-fill car aircon...   ;)


Title: Re: Fridge, you'll kill us all.... :o)
Post by: dhaslam on November 15, 2010, 12:10:49 AM
What temp is a fridge supposed to be at?? A Google says 3 to 5deg C but where in the fridge? The rear wall is at -18 (running) where the evaporator coil is with ice crystals forming, the milk in the door is at 6deg C and the glass of water on the middle shelf is at 4 to5 deg C, bacon on the bottom shelf at 2deg C. I wish I'd had the foresight to measure the temps a month ago when it was hunky-dory... Will need to start carrying a temp gauge and measure fridge temps wherever I go  ::)

Fridge thermostats seem to be placed around the centre  and normal setting is about  5C.   The bottom  becomes a little bit colder  and the top a bit warmer but within about one degree either way.   My fridge stopped working last week  and was indicating 12C  but actually the temperature at the bottom stayed around 8C  which is reasonably OK.   Incidentally Samsung repaired the fridge without charge even though it was out of warranty because they accepted that  there was a design fault  in the defrosting system.     


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Ivan on November 15, 2010, 02:02:52 AM
Excellent bodging! Especially the tyre valve. If anyone needs one of these for a similar bodge, let me know - I've got a few hundred brand new ones in my toolbox.

One question - did you fill with gas or liquid (ie was the bottle inverted or right way up?). Did you have any trouble getting the quantity to decant (did you need to heat the gas bottle?). Incidentally, if you invert an old propane bottle, you'll get a lot of dirt and heavy ends go through which won't do the fridge much good.

A friend of mine did this with his old CFC fridge under similar circumstances in the early 90's Last time I heard, the fridge was running perfectly, several years later. He did something quite clever - he overfilled it, then measured the cycling time (ie how long ON, how long OFF) with a stopwatch, whilst he watched TV in the evening. Once he'd worked out a baseline, he released a little gas, then did it again. The fridge was on for less time. He released a bit more, and timed it again. He did this until he reached a minimum...but of course, didn't know this until the 'On' time increased again. Once he knew the shortest time the fridge was capable of, he just refilled it a little and repeated, but this time stopping once he got to the optimum 'On' time.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: camillitech on November 15, 2010, 08:06:14 AM
Fantastic work Heinz,

I don't care how inefficient your fridge is, it's a far smaller carbon footprint than manufacturing a new one, well done.

As for Biff's mate and the circular saw, well that was much worse than when I used stainless steel rigging wire in mine cos I'd run out of cord  facepalm

Cheers, Paul


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 15, 2010, 10:04:05 AM
One question - did you fill with gas or liquid (ie was the bottle inverted or right way up?). Did you have any trouble getting the quantity to decant (did you need to heat the gas bottle?). Incidentally, if you invert an old propane bottle, you'll get a lot of dirt and heavy ends go through which won't do the fridge much good.

I filled with gas rather than liquid. If you just open the valves only a smidgen of gas will transfer before flow stops, but turn the fridge on and the compressor sucks the gas in quickly, 15? seconds for 40g.

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: rhys on November 15, 2010, 11:57:42 AM
Fantastic work Heinz,

I don't care how inefficient your fridge is, it's a far smaller carbon footprint than manufacturing a new one, well done.

As for Biff's mate and the circular saw, well that was much worse than when I used stainless steel rigging wire in mine cos I'd run out of cord  facepalm

Cheers, Paul
Is that true?
I thought the energy use/ footprint of a fridge was about 20% manufacturing and 80% energy use,over its life time,  even with a relatively modern fridge.
So replacing a 5 to 10 year old fridge makes sense, given that it should use roughly half the energy of an old fridge.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: camillitech on November 15, 2010, 12:23:32 PM
Fantastic work Heinz,

I don't care how inefficient your fridge is, it's a far smaller carbon footprint than manufacturing a new one, well done.

As for Biff's mate and the circular saw, well that was much worse than when I used stainless steel rigging wire in mine cos I'd run out of cord  facepalm

Cheers, Paul
Is that true?
I thought the energy use/ footprint of a fridge was about 20% manufacturing and 80% energy use,over its life time,  even with a relatively modern fridge.
So replacing a 5 to 10 year old fridge makes sense, given that it should use roughly half the energy of an old fridge.

You could well be right Rhys,

I am however really skeptical about these claims, for a start if the fridge is made in China by a coal fired power station then shipped here in a mega container ship using heavy oil is that taken into account  ??? or how about the energy required to remove the gas from the old one and then ship it back to China to be turned into a million other bits of cr4p we don't need.

I know you could go round in circles for years debating this and at the end of the day still be no wiser. I mean this whole 'carbon footprint' things all a bit vague anyway. At one time all the power stations were coal but at least they were British coal and usually mined right next door. What's the true price of keeping the oil and gas flowing in terms of all the embedded energy in an aircraft carrier or submarine  ;D

I'm not saying you're wrong, I'm  just saying that I've not got a clue  surrender:

Cheers, Paul


Title: Re: Fridge, you'll kill us all.... :o)
Post by: rhys on November 15, 2010, 02:17:05 PM
I agree it's very difficult to calculate and agree Life Cycle energy costs.
Generally I take the view that unless something is a heavy energy user then make do and mend is the answer.
But low energy replacement items that replace higher energy things are usually worthwhile. Eg. Lightbulbs.
Embodied energy is important but is often a fraction of the overall energy impact E.g PV panels.
The worst thing about replacing old fridges that still work, is that so many people put them in the shed and use them as beer fridges, defeating the whole point of the nice new energy efficient fridge in the kitchen. facepalm


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Ivan on November 17, 2010, 03:48:52 PM
For some products eg cars, embodied energy is very high. For other products that are smaller and used constantly or for long periods, the embodied energy becomes a much smaller part of the overall cradle-to-grave energy count. Fridges definitely fall into that category. I bet there's at least one manufacturer that's done a carbon footprint analysis - in which case you could work it out.

Older fridge half-height fridges and freezers can use up to 1.5kWh/day. A new A+ rated equivalent one could be using 0.35kWh/day.

Don't overestimate the cost of shipping from the other side of the world. We ship solar panels half-way round the world, so we have done a carbon calculation, and it's surprisingly low. For a Navitron solar panel, the cargo ship energy cost is around 2litres of fuel per panel (similar volume and weight to a fridge).

For many of us, we think long and hard about this kind of energy cost, and don't think twice about nipping down to the local shop in a landrover, which will have a greater carbon cost


Title: Re: Fridge, you'll kill us all.... :o)
Post by: camillitech on November 17, 2010, 04:37:42 PM
I'm sure you're right Ivan,

far more intelligent folk than I have perused over this subject and I don't want to get into an argument about it but these things seldom end in the 2lts of fuel to ship it from wherever. There's not only the cost of the ship required but the disposal of said ship afterwards. Then there's all the cr4p that less conscientious capitalists ( and I'm a bit of one myself  ;D ) will buy with the profits made on said fridge.

Don't get me wrong, if we did not make and buy 'stuff' then everything would go t1t5 up, I'm just saying it's a little more complicated and I'm firmly of the school "if it aint broke don't fix it and if is broke fix it if you can". Which is why I drive a 24 year old LandRover, OK it may only do 24mpg but most of the original components have never traveled more than 400 miles from where they were manufactured  ;D

Cheers, Paul 


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 21, 2010, 02:32:56 PM
Older fridge half-height fridges and freezers can use up to 1.5kWh/day. A new A+ rated equivalent one could be using 0.35kWh/day.

Just a wee fridge update.
I bought a plug in energy meter (B&Q branded "airforce" off Ebay) and it claims the fridge is using 0.67752 Kw per day. Assuming the meter is accurate, I'm happy with that  exhappy:

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Justme on November 21, 2010, 05:09:29 PM
Older fridge half-height fridges and freezers can use up to 1.5kWh/day. A new A+ rated equivalent one could be using 0.35kWh/day.

Just a wee fridge update.
I bought a plug in energy meter (B&Q branded "airforce" off Ebay) and it claims the fridge is using 0.67752 Kw per day. Assuming the meter is accurate, I'm happy with that  exhappy:

Heinz

0.67752 Kwh using 0.67752 Kw all day would be 16kwh.

Thats double what my larder sized one uses.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 21, 2010, 05:55:28 PM


0.67752 Kwh using 0.67752 Kw all day would be 16kwh.

Thats double what my larder sized one uses.
[/quote]

Oops! missed out the "h" ...... 0.67752 Kwh per day. That was yesterday.

Checked it again today, 9 hours so far and it's used .27 kwh over the 9 hours.
0.27kwh over 9hours = 0.27kwh over 540mins
0.27kwh divided by 540mins = 0.0005kwh per 1min
0.005 x 1440mins = 0.72kwh per day ??
Feel free to sort out the maths, never was very good at it.....

Heinz

edited to remove the  / from me kwh's


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Pat_ on November 21, 2010, 06:07:52 PM
Don't want to be picky but it is quite important really. Kw/h is wrong it should be kWh.

The '/' means per, and what you want to say is kW multiplied by hours not divided by them.

Exit stage left...


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 21, 2010, 06:17:22 PM
Don't want to be picky but it is quite important really. Kw/h is wrong it should be kWh.

The '/' means per, and what you want to say is kW multiplied by hours not divided by them.

Exit stage left...

OK, won't make that mistake again...

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Pat_ on November 21, 2010, 06:47:02 PM
Actually, got so obsessed with that, that I forgot to say how impressed I was with your engineering experiment. You are clearly a person who can take theory one step further. Respect.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Eccentric Dyslexic on November 21, 2010, 09:20:32 PM
Ok next job for ya... remove and weigh all the gas from a 12kw Heat PUmp to check if the right amount is still in there... crack:

Steve exhappy:


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 21, 2010, 10:17:31 PM
Ok next job for ya... remove and weigh all the gas from a 12kw Heat PUmp to check if the right amount is still in there... crack:
Steve exhappy:

I know you're just taking the p*ss  ;) But if you really wanted to do it could you not use a redundant fridge compressor to pump it out into an empty (carefully chosen for size) gas bottle? You could evacuate the gas bottle with the fridge compressor first, then weigh it, then pump your gas into it, re weigh and pump it back into the heat pump. The only problems are going to be the small lost volume in the pump/hoses/bottle and some contamination with whatever dregs the gas bottle still contains once it's evacuated, unless the bottle is the right one for your gas or you have some spare correct gas to purge everything with first. Why would you want to though??
Hook, line and sinker...

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: billi on November 21, 2010, 11:11:48 PM
Heinz have an applaud for you and your fridge

Billi


Title: Re: Fridge, you'll kill us all.... :o)
Post by: SteveH on November 21, 2010, 11:23:25 PM
 & another... ;D


Title: Re: Fridge, you'll kill us all.... :o)
Post by: fje-iptelenet on November 22, 2010, 12:15:13 AM
and one more for keeping goats a horse and two dogs.................keep up the good work!


Title: Re: Fridge, you'll kill us all.... :o)
Post by: camillitech on November 22, 2010, 05:39:21 AM
and one more for keeping goats a horse and two dogs.................keep up the good work!

and a Land Rover  ;D though anyone who keeps goats must have a screw loose anyway  ;D

Cheers, Paul


Title: Re: Fridge, you'll kill us all.... :o)
Post by: knighty on November 22, 2010, 08:38:06 AM
industrial fridges (and I'm assuming heat pumps) have an accumulator just after the condenser (hot bit) as somewhere for the refrigerant to collect up as a liquid and to help collect the oil - the liquid refrigerant comes in the top and and out of the bottom - so if you loose a bit of refrigerant the pressure drops and there's a bit of gas at the top of this small tank/bottle but there's still liquid at the bottom and going out to the evaporator (cold bit) (there's normally a very small oil return pipe going to back to the compressor too)

it's a bit like a small reservoir so as you loose a bit of gas, and as a buffer so as the weather changes and changes the pressure in the gas side of things changes it doesn't effect the way the system works... (but they're never great.... they need quite a bit gas pocket at the top for the changes in weather, so there's not enough liquid in the bottom to make up for loss or gas)


but I've always thought.... there should be another (bigger) tank between the high pressure side and low pressure side, with pressure valves connecting it to each... too much pressure in the high side and refrigerant is let in..... too little pressure on the cold side and some is let back out into the system....

that way you could have a decent amount of refrigerant in it..... and the system would stay at the right pressure for years.....

I have to have mine at work gassed up every year.... could maybe get away with every 2 years but it's not worth the loss in efficiency.... and that's with pretty new systems, 2 of them are less than 3 years old and still need it !


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Eccentric Dyslexic on November 22, 2010, 09:43:58 AM
Ok next job for ya... remove and weigh all the gas from a 12kw Heat PUmp to check if the right amount is still in there... crack:
Steve exhappy:

I know you're just taking the p*ss  ;)

Who sed i was jesting  exhappy:

My HP takes 1.3Kg of R407c and 1l of oil.  I suppose i could refill the system via a filter/dryer to make sure the gas is nice and clean and dry....?  I can buy bottles of R407c off of eBay wacko

Steve :hysteria


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 22, 2010, 12:16:50 PM

it's a bit like a small reservoir so as you loose a bit of gas, and as a buffer so as the weather changes and changes the pressure in the gas side of things changes it doesn't effect the way the system works... (but they're never great.... they need quite a bit gas pocket at the top for the changes in weather, so there's not enough liquid in the bottom to make up for loss or gas)


so there's a wee tank, liquid in the bottom, gas in the top. Couldn't you use one of those cheap magnetic thermal strip gas cylinder level gauges to "see" the level of the liquid in the reservoir and top up if it's low?? Or is the temp change between the gas/liquid not great enough?

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: knighty on November 22, 2010, 12:25:24 PM
yeah it's all the same temp (quite warm!)

another thing I forgot to say is, industrial compressors (and I guess heat pumps?) "pump down" just before they turn off - the solenoid letting liquid through to the evaporator (cold bit) closes but the compressor keeps pumping and sucks the gas side empty pumping everything into the accumulator and high pressure side...

they do that so there's no chance of any of the refrigerant in the gas/cold side condensing back down to liquid and being sucked into the compressor and damaging it

in domestic fridges when they compressor shuts off, the pressure equalises around the system and all the liquid refrigerant drops down to the lowest point.... which is in the bottom of the compressor - they only have enough refrigerant in to fill the bottom of the compressor (where the motor is) the top of the compressor is above that level and in gas :)


as you might have guessed..... refrigeration engineers charge a fortune so I've done a lot of reading up on the subject !!


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 22, 2010, 01:11:17 PM

and a Land Rover  ;D though anyone who keeps goats must have a screw loose anyway  ;D

Cheers, Paul

A LandRover? I wasn't aware that you could only have one?! I thought they were herd animals???
1966 109 GS canvas top - my wheels :) general workhorse,  Lpg
198? 109 FFR Canvas top - sleeping
1973 88 hard top - long term project
1953 86 series1 hard top - awaiting rebirth one day if I ever have the time.
1991 127 RAF ambulance - current favorite, v8 Lpg camper, doesn't go far and not nearly as thirsty as you'd expect.
1990 110 RAF station wagon - not sure what to do with this one but it's eating no grass.
197? 88 pickup - spares.
some others being recycled into other things (that's real recycling, not "recycling") and slowly being reclaimed by the earth...

Just in case someone jumps on the anti 4x4/gas guzzler bandwagon. We really do need a 4x4, a Ford KA would not make it up the 750 foot hill dirt track for long, would not be able to bring the firewood out of the forest, would not get us home in the winter and would not get the kids to school in all weathers. A (real) LandRover does all this and will probably still work for the kids when I'm long dead...  ;D

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Stevie D on November 22, 2010, 04:33:45 PM
Quote
A LandRover? I wasn't aware that you could only have one?! I thought they were herd animals???

 :)

I must tell the wife that one, I've just bought a 3rd.

Love the home made mill as well - excellent work on the fridge too!

Steve


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on September 01, 2011, 07:59:30 AM
Well, that's about 10 months and the butane fridge hasn't missed a beat  exhappy: although by saying that, I've probably jinxed it  facepalm
I do have a small problem with it though. The condensation dish on top of the pump no longer gets warm enough to evaporate the accumulated water, dish overflows and the water run out onto the floor. Any bright ideas to avoid me getting abuse from the rabble and having to dry up the mess once a week? Best I can come up with is a bit of tubing shoved in the drain hole and a milk bottle beside the fridge..... not sure how well that will go down with the woman though.  My other idea is a wick dipped in the dish, which goes up to the warm condenser, but it would probably just end up mouldy.

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Justme on September 01, 2011, 10:55:03 AM
Well, that's about 10 months and the butane fridge hasn't missed a beat  exhappy: although by saying that, I've probably jinxed it  facepalm
I do have a small problem with it though. The condensation dish on top of the pump no longer gets warm enough to evaporate the accumulated water, dish overflows and the water run out onto the floor. Any bright ideas to avoid me getting abuse from the rabble and having to dry up the mess once a week? Best I can come up with is a bit of tubing shoved in the drain hole and a milk bottle beside the fridge..... not sure how well that will go down with the woman though.  My other idea is a wick dipped in the dish, which goes up to the warm condenser, but it would probably just end up mouldy.

Heinz

Our fridge was like that from new. In the end I piped it through the floor to a drain. Not easy to move the fridge now but better than a spill.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Eccentric Dyslexic on September 01, 2011, 12:02:28 PM
The wick idea is best, maybe an old cotton rag with the bottom in the dish and the top against the condensor, its heat will keep it dry at the top, encouraging more water to be drawn up into the rag.  i wouldnt worry about the mold, it shouldnt cause much of a problem as it will be mostly dry, try it and see.

I'm wondering why your pump is not getting hot, maybe the new gas is so much more efficient the pump isnt running long enough for it to get hot:-)  The pipe coming from the pump gets hot though doesnt it? 

Another point to improve efficiency, try running a little pc fan to blow on the condensor when the motor runs....have a play with that and re do your kw/h test...

Steve


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on September 01, 2011, 01:03:33 PM

OK, added a rag to the fridge. About a foot long bit of denim, inch and a half wide, dipped in the dish and woven up the condenser bars. The PC fan is a good idea, but I think they are normally 12 volts? Suppose I could use an adapted cheap plug transformer from the pile of cast off chargers in the shed, going to reduce the efficiency though...

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Eccentric Dyslexic on September 01, 2011, 03:45:05 PM
I would have thought efficiency should improve, normally, the condensor relys on convection to cool the rails on the back, but if you use a fan to aid convection it should help.  Our A++ rated Samsung yankie FF has no rails on the back...it uses a fan to cool the output from the condensor.

One simple way to see if it helps is to monitor the temp of the pipe at the far end of the condensor rail before it goes into the back of the fridge, if its cooler with the fan, the fridge will be more efficient....nice little experiment anyway! wacko 'Leccy consumption will go up a tad due to the fan, but run time should reduce... :laugh:

Steve


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on October 07, 2013, 12:11:52 AM
The fridge regassed with propane is still running well  ;D  Still had trouble with the lack of heat to evaporate the condensed water from inside the fridge though. The water runs down inside, through a drain to the dish on top of the compressor which is supposed to be warmed enough by the waste heat from the compressor to evaporate the water.
This worked fine on the original gas, but the system runs much cooler on propane resulting in the evaporation dish overfilling and the water ending up on the kitchen floor.
Tried various absorbent things woven into the hot condenser on the back and dipped in the evap. dish. Nothing really worked very well....
I'd added a bit of tube and a syringe, so I could drain the dish without having to move the fridge but it was a bit of a PITA. Got a couple of feet of 10mm copper pipe, pushed the end directly into the water drain tube from the inside of the fridge and this now feeds the condensed water into an easily emptied jam jar on the floor beside the fridge. I was sure this would work, but there was still water on the floor. Turns out the suction pipe from the inside of the fridge to the compressor is cold enough to condense the moisture in the air which then freezes onto the pipe and melts when the compressor pump stops running. Got half a dozen bog roll tubes, carefully masking taped them round the rather awkward suction pipe (it's far from straight) and filled them with spray foam, so the suction pipe is now mega insulated  ;D
No more water on the floor so the woman is happy, or rather the woman is as happy as most women would be with an old bodged fridge, copper pipe and jam jar.... Yup, she's not happy at all  :hysteria

H


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Eccentric Dyslexic on October 07, 2013, 06:54:59 AM
Yep my swmbo is never happy with a bodge either! Lol

Steve


Title: Re: Fridge, you'll kill us all.... :o)
Post by: daserra on November 18, 2013, 01:44:36 AM
The modern gases are all blends with differing gases with different evaporation points so should be filled with an upside down bottle to get the liquid BLEND into the system. Rule of thumb; if the system freezes up (on the outside of the pipes) you're running too cold and there's not enough gas. Do yourself a favour and get a cheap manifold so you can charge to the correct pressure. 25 bucks should do it.
Great work soldering that nipple on there !


Title: Re: Fridge, you'll kill us all.... :o)
Post by: derekmt on November 18, 2013, 10:16:36 AM
Are you supposed vacuum pump the system before filling?


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 18, 2013, 10:19:20 AM
You're probably right, gas blend, manifold, etc. But it's running fine on the Butane (no idea why I said Propane a couple of posts back), the suction pipe is causing no trouble now it's insulated, the water in the jam jar is minimal, maybe half a jar a week? so I'm not going to interfere...
If it ain't broke, don't fix it  :hysteria

Tiny bit of fridge madness though, the handle cracked ages ago so we've been using it handleless which is OK, but I was casting some fire grates for a bloke in the village and made these while the furnace was still hot. First one not perfect, second one OK  ;D
(http://www.goatpark.force9.co.uk/assorted/handlemold01.jpg)
(http://www.goatpark.force9.co.uk/assorted/handlemold02.jpg)
(http://www.goatpark.force9.co.uk/assorted/done01.jpg)



Title: Re: Fridge, you'll kill us all.... :o)
Post by: biff on November 18, 2013, 10:29:32 AM
Wow Heinz,
            Nice bit of work.I have a pal on top of the mountain and every few months he lights a fire under a barrell,chucks in broken alloy bits of manifolds,gearboxs and diffs to melt down.Then he pours the lot into these round moulds of different sizes.He makes casings for bearings and tells me it is the easiest job in the world,Very sore on the coal supply.
                                                              Biff


Title: Re: Fridge, you'll kill us all.... :o)
Post by: knighty on November 18, 2013, 11:00:44 AM
those look really good, I'm impressed!

(better than the casting I had done at a foundry tbg)


Title: Re: Fridge, you'll kill us all.... :o)
Post by: mespilus on November 18, 2013, 04:29:30 PM
A mate of mine 20+ odd years ago was looking round scrappers on the western edge of London
for Viva parts.

At one place he saw a 200 litre drum over a fire ........
....... with the engine of a Hillman Imp sticking out of it,
slowly sinking into the ferment of liquid aluminium alloys.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: daserra on November 18, 2013, 08:02:24 PM
Excellent handles, wow ! You can cheat vis a vis the vacuum by pushing out the air with the refrigerant. Not sure how you'd do that in a fridge though but on split AC you open the tap without the Schraeder filling valve to pressurise the lines, then close it and bleed off the air. Rinse and repeat then open both taps.


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on September 07, 2017, 11:55:20 AM
Well, it's been about four oops, Seven years since the fridge got regassed with Butane and all has been OK until recently. Noticed the fridge was running more than normal and  not working as well as it should. SWMBO is away in Belgium, so I'm free to mess around with such things in the house with zero interference/paranoia for a while  ;D
Checked the pressure, next to nothing and the pump is HOT, so all is not well. Left it to cool for a while and drained the residual pressure, horrible hot electrical smell and almost no gas smell. Regassed with 40g or thereabouts of Butane from a camping gas cartridge, fired it up and I'm waiting to see if it ok before pushing it back into place in the kitchen. I really hope it runs for a while as she wants to get one of those American style fridge freezers (has to be red) and I would rather not spend many hundreds on such a thing.... I have no need for a water cooler and ice maker  ::)
Cheers,

H
p.s. I notice the photos have disappeared from this thread, seems to be a lot of older forum posts on the net have lost their pics recently, shame as much info that was researchable is now as good as useless ...   ???


Title: Re: Fridge, you'll kill us all.... :o)
Post by: camillitech on September 07, 2017, 12:25:53 PM
Aye H, good to have you back,


I notice the photos have disappeared from this thread, seems to be a lot of older forum posts on the net have lost their pics recently, shame as much info that was researchable is now as good as useless ...   Huh


That'll be cos of this https://www.navitron.org.uk/forum/index.php/topic,28643.0.html


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on September 07, 2017, 01:25:50 PM
That explains it....   Blo*dy Photobucket....    :'( 

H


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Fionn on September 07, 2017, 01:37:05 PM
Do you still have the original photos? Would be cool if you could edit the original post and replace them.
Great thread and outcome by the way!


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on September 07, 2017, 01:57:44 PM
I will have them somewhere, but they will be on one of the older PC's or one of the many backup hard drives in a box in the attic or on backup CD disc or a 'just in case' flash drive. Life was simple when we just got 35 prints from a film at Boots and kept them in a shoebox under the bed, too easy to take photos now and everyone has thousands stored on drives that will probably never be looked at again after a very few years....
I do sometimes have plans to sort it all out, but there are always more important things to do.
Thread is drifting a little here, all my fault  whistle
I do wonder if these cloud storage things will bite people in the arrse in a similar way to Photobucket??  We get convinced to store all our photos on Amazon or wherever, then A/ we are hooked and end up paying forever when the tempting free space is used up, B/ if they lose them, there will be no comeback, C/ their terms will change over time and they will end up being able to use/search our pictures without our permission, D/ what happens to my photos when I die?? Are they lost on a cloud server somewhere? does the cloud Co. aquire them?? 
Similar to cars on lease instead of buying, you never own it. Software that we used to have on our PCs, now it's 'online' and we no longer have control or ownership. I resist all such things..

H


Title: Re: Fridge, you'll kill us all.... :o)
Post by: todthedog on September 07, 2017, 02:31:48 PM
Blackmail
Heinz we are going in the opposite direction, Old albums of photos needed to be scanned for posterity or rather to print in book format for Mrs T's dotage. My computer is rammed with pictures that I had little interest when taken and even less now. at least with the old printed ones film and developing was quite expensive limiting the numbers together with natural incompetence further reducing the numbers
 


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Fionn on September 07, 2017, 02:37:17 PM
Definitely drifting OT, but on Google Drive at least, the invasion of privacy is immense.
If you take photos on your android phone and have them backed up to google drive (default setting) then google scan every one for object recognition and OCR.

I was searching for a bill recently and found a photo of a bill which had not been renamed in any manner, the photo had obviously been OCR'd.
Similarly I searched for a file with "meter" in the text and it brought up all maner of photos of electricity meters, energy meters etc that I had taken or were in my WhatsApp photos!


Title: Re: Fridge, you'll kill us all.... :o)
Post by: Heinz on November 13, 2018, 12:41:36 PM
The Fridge is dead, long live the Fridge Freezer!!!
The door seal was falling to bits and it suffered from condensation on the cold pipe from the compressor, which I had carefully insulated and attached a drain system to. Anyway, after much badgering and complaining, I was talked into buying a new fridge freezer for a sum of money that proves that I am the fool !!
https://www.robertdyas.co.uk/russell-hobbs-rh90ff176r-wide-american-style-fridge-freezer-red?istCompanyId=bf3344d9-83f5-4abd-b69a-da131f7567d1&istItemId=xlllwrwrwx&istBid=tzxx&source=&gclid=EAIaIQobChMI-tyn57HR3gIVbLXtCh2QEQuqEAQYASABEgIhHPD_BwE
there are some of these on ebay with minor? damage for mucho cheapness, but I chickened out, women tend to be much pickier than blokes??  and it was long term ear grief I don't need.

It seems Ok, but the freezer could be bigger and will be when I throw away the ice maker which wastes an entire shelf just on the off chance that I would use it to ruin my whisky...  :o

The delivery blokes were extra helpful, unpacking, lifting it in, etc. which was good as I was away at work, but they also helpfully removed the old fridge and freezer which delighted the woman and disappointed me  :(  I had plans for the compressors and my workshop needed another couple of fridge based cupboards. Oh well....   ;D
Cheers,

Heinz


Title: Re: Fridge, you'll kill us all.... :o)
Post by: eabadger on November 13, 2018, 01:03:09 PM
we bought something similar 4 years ago in the sale, only difference seems to be our freezer is two big drawers at the bottom and all the top fridge.
so far so good, power consumption well down on what the old Bosch one used and no food going off, we thought the fresh chicken was not so fresh and some went off, seems the old fridge was not getting cold enough, we can now see temp and when kids leave doors open it kicks off!!