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Author Topic: Riello oil burners...any good?  (Read 30714 times)
Cliff top
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« on: December 07, 2014, 07:18:38 PM »

Although my Arrow Stratford has provided nearly all our heating needs for the past 7 years, the system also has an old 1985 myson oil boiler still plumbed in which can be used on a timer to take the chill off on a cold morning.

The myson part is just the steel box really, and has a red 1999 Bentone sterling burner unit....the one with the Satronic tf830.3 control box.....for which my personal opinion is that its an unreliable clockwork control box  wackoold

Its this burner unit that is again giving me problems...  surrender
I've had 3 satronic boxes, new flame photocells, a new spark generator and numerous sessions of tinkering to keep it going/ stop it going to lockout over the years. .

Anyway its failed again, no oil jet now. Sounds like ignition is trying, but maybe no oil is pumping, or solenoid not releasing... But I don't think its the satronic this time as all 3 are the same...and the other 2 were usable to some degree.
A big bulge is again present on the side of the ignitor.....maybe this is failing again?...

I fancy swapping the whole thing for a new burner...a Riello one plus control box. Easy swap it seems.
Can anyone offer an opinion on whether these are reliable and worth the effort?

As my heating system is vented, having the myson, a logstove, and a 250L store etc, I am limited to a boiler that runs without pressure, and with the myson basically being sound, a burner swap is the least work/cost option....especially as I only use maybe 100L! oil a year.

Any help appreciated.

Cheers
cliff.
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biff
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« Reply #1 on: December 07, 2014, 07:30:25 PM »

For what it is worth,
                  Riello burners are among the best that money can buy,Make sure that you filter the oil for water because if the water gets into the little pump,it will rust its insides and kill it.
  Yes they are good and very easy installed. I have only ever had one pack up and that was because of water in the oil, Years ago. I was told not to waste my time on any other make.
                                                                                                      Biff
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Billy
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« Reply #2 on: December 07, 2014, 08:13:24 PM »

Three barges use them here, so do I, brilliant things, easy to service and cheap (ish) spares.  Industry standard really.  Super.   extrahappy
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Countrypaul
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« Reply #3 on: December 07, 2014, 08:20:34 PM »

I have a Trianco oil boiler which has a Riello burner and generally has been trouble free. Have had a couple of sessions over the last 20 years where it has had problems. First major problem where it had to be stopped cause of too many fumes coming out and 2 inche of oil in the bottom of the boiler was traced to water in the oil and the pump corroding and slowly seizing up. the plastic tank has no drain on it and I was told it doesn't need one ! I siphon off any collected water every autumn now! The engineer took the burner away to fix as he couldn't get it apart on site and I was about to go away for a week so he brought it back a week later when I got back. Took him and hour or so to get most of the oil out he bottom of the boiler and a further couple of hours for it all to burn off and stop fuming/smoking.

As Biff says keep the oil free of water and things should run without problems. A second issue I have had was intermittent operation where the boiler would start then cutout. I eventually traced it to one of the screw down connections for he control box not being tight. Have been a couple of occasions where the magic eye has got sooted up and then the boiler would not fire properly, but other than those issues I can't remember any other problems. The jet is changed annually and the flexible hose has been changed at least once but these are just routine.

Paul
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Philip R
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« Reply #4 on: December 08, 2014, 12:39:40 AM »

Cliff Top
Riello burners are as good/bad as any other burner. From your tales of woe, sounds to me that you have not actually found out why it fails so why would a new burner fare any better?

The Satronic boxes are not unreliable, but a lot cheaper than the Riello and Siemens/ Landis & Gyr boxes.

Your mention of the ignition transformer bulging indicates the spark is being maintained too long, exceeding the duty cycle of the transformer and cooking it.
Suggest you get the boiler properly serviced including a full clean /de-clag of the combustion chamber, heat exchanger, baffles and flue, to eliminate back pressure issues. Also, as mentioned, the oil supply system is clean and free of water and crud entering the burner fuel pump.
From your lack of oil consumption and the use of the words "least cost", I would reason that the appliance has not been recently fully serviced?
Get the system looked at by a competent person, who can follow the industry standard (OFTEC) oil service procedure,and the fault should become apparent.
Philip R

Philip R

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julian
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« Reply #5 on: December 08, 2014, 10:04:21 AM »

Cliff,

Riello are fine, but dont try to burn any non-standard fuel in them.  28sec is fine.

I, and others, have tried bio, and its a whole load of bother (we now have a 1980s vintage, electro-oil burner, with settings for 'gas oil' 35sec, and it burns bio fine)


If you want a riello burner....

I bought a whole boiler for the heat exchanger / enclosure.  It has a riello burner in it, which ive not even turned on (as i already know it wont burn bio, and i have the electro oil unit that ill fit into the new housing)

If youre keen, ill fire it up on some kerosene, so we can both see it running, and if you would like to offer me somewhere a bit under whatever they go for on ebay, its yours.  Off the top of my head, i suspect 40 would be a sensible price, but, really, ive not looked for some time.



But, aside from any of that, im sure a cheap, drop in, riello will sort you out, and i suspect their used price (from me, or anyone else) is less than i paid for the replacement pump for my electro-oil unit alone!

...but, again, theyre no good for thicker fuels.  Some (riellos) are rated for 35sec, but im dubious of even them.
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« Reply #6 on: December 08, 2014, 10:12:31 AM »

As for repairs -

You sound as if you have some history with the unit, but, just to check -

If you remove the nozzle, does it pump oil from the end of the pipe?
Does it have a bulge anywhere on the high pressure pipe?  Looks like a compression coupling?

If so, (if its not pumping oil) have a look in there.  It would be a sprung loaded non-return-valve, which some, but not all, burners have.  (my friend has an identical burner to me, in all respects, except for the NRV was present on one but not the other)

Im guessing theyre to stop dribble / to act as a mechanical pressure switch, rather than a valve as such - anyhow, they can seize (the plunger swells).


If no oil still, could be the solenoid on the pump (but they cost as much to replace as an entire pump, it seems!)

Some pumps also have a mesh filter on the low pressure side.

Beyond that, if theres no oil, its probably new pump time (assuming, of course, youre sure theres oil on the inlet!)


If there's oil, then on to ignition, but, from your post, it sounded like you suspected a flow issue first?
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Cliff top
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« Reply #7 on: December 08, 2014, 04:09:08 PM »

Thanks for all the input.  The Riello, does seem the answer and your votes of confidence help in that direction.

I'm both an electronics engineer and competent plumber/DIYer etc, so have a lot of experience with this burner now.  I 'service' it each year, cleaning the boiler chamber, removing/replacing the plates and tweaking the oil/air mix for a nice white flame. There is a filter inline and I only use normal heating oil. 
The outside draughty boilerhouse isn't a good environment and sandblasting the house the other year didn't help, so I shouldn't moan about it being unreliable, I should expect it. tomatosplat

The original ignitor would it seems have failed how this one may too, by being constantly in use (though its never on more than an hour...and then only on the coldest mornings).
The first time (yrs ago) I had a fault,  I changed the CDS sensor before discovering it was both the Satronic box and the ignitor I needed.  The TF830.3 box has 3 switches moved by a heater round a bimetal bar. If not moved for a few months one of the C shaped springs stays compressed and one switch fails to click...hence my description as 'clockwork'. The rest of the box is surface mount components and seems engineered just fine....but the mechanical bit doesn't like the damp conditions I suspect.

I've disconnected the HP thin oil line to the jet and this blows though ok.  Oil is getting to the pump, ok, and the fan/pump runs just fine. So at this point I suspect the solenoid isn't firing to release the oil.... but for what reason?  I can't find a fault finding flowchart like the Riello one I found last night... (fantastic to have a step by step procedure chart including resistances to check for etc). Maybe the control box doesn't trigger the solenoid until it detects spark? maybe the rusty looking solenoid or it's coil is at fault... I need to get it all on my bench at work to find out.  2 hours yesterday in a cramped cold boilerhouse without all my best diagnosing tools was the last straw.

Julian,  yes I'm interested in the used burner..  I'll send a PM.. Cheers Cliff
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Tinbum
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« Reply #8 on: December 08, 2014, 04:47:18 PM »

A burner of mine has a 'key' made of copper that connects the pump shaft to the fan / motor and that used to wear and result in no fuel to the nozzle. An old consumer unit had some good copper bar in it to make a new key.

Have you measured for a resistance across the solenoid coil?
« Last Edit: December 08, 2014, 04:49:11 PM by Tinbum » Logged

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« Reply #9 on: December 08, 2014, 07:24:55 PM »



I've disconnected the HP thin oil line to the jet and this blows though ok.  Oil is getting to the pump, ok, and the fan/pump runs just fine. So at this point I suspect the solenoid isn't firing to release the oil.... but for what reason?  I can't find a fault finding flowchart like the Riello one I found last night... (fantastic to have a step by step procedure chart including resistances to check for etc). Maybe the control box doesn't trigger the solenoid until it detects spark? maybe the rusty looking solenoid or it's coil is at fault... I need to get it all on my bench at work to find out.  2 hours yesterday in a cramped cold boilerhouse without all my best diagnosing tools was the last straw.


The solenoid is controlled by the 'controller'.  The solenoid allows the motor to start, spin up, etc. before the load comes on.  I guess (and it is just a guess) that this puts a touch less strain on the motor, but i think the real reason is to that the fan and the oil are independent with an added bonus that there's a quicker start to the flow / less dribble on firing.  The valve is a bypass, rather than an on/off thing.

Modern riello burners blow air through the exchanger for a while before turning on the oil and igniting.  I assume this is a saftey thing (clears potentially explosive gasses before the transformer / electrodes fire) - i possibly read that in a manual once, but, again i wouldnt bet on my memory!

My electro oil unit has a solenoid, but, as i recall, it opens up as soon as the fan starts (we dont have an oil boiler plumbed in at the moment - just the rayburn)


Anyhow, regardless of the reason for the solenoid, you could just wire it to live, at least for testing.  The boiler wont continue to burn when the pump stops, but do check that the oil does not continue to leak through the pump under gravity (ive used even older burners before, that dont have a solenoid at all, and they did not leak, but best to make sure, i think!).

All the solenoid is is a (removable) ring, with a fixed (to the pump) valve in the center.  The ring comes off easily.  Ive never tried it, but i suspect a nail through the coil center (where the valve would be) would tell you if / when it energies?  If the field induces a million volts into the nail, im not to blame, right? : )


One trick that you may do anyhow is to shine a torch at the photocell at a sensible time.  It 'tricks' the controller to think the flame is lit, and gives you more (well, as much as you like) working time before the control box goes to lock-out.
« Last Edit: December 08, 2014, 07:27:52 PM by julian » Logged

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sb79
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« Reply #10 on: December 08, 2014, 07:57:55 PM »

Cliff, I am heating engineer/plumber and my take on burners is this- ecoflam=rubbish. Riello=ok. Bentone Sterling=ok. Inter=okish.

Which would I prefer to see and service? Well there's not much in it in my opinion but parts are much cheaper for bentone and inter.

All new boilers from the top 4 selling makes grant/Worcester/warmflow/firebird use riello so I guess that's a pretty good endorsement.

However, you evidently have a problem with that particular boiler which you have not got to the bottom of which is the source of your problems. Also you mention that you service this burner yourself? Can I ask if you are using a flue gas analyser to set it up? This is the only way to set up a burner correctly.
"A nice white flame" is a very bad thing. It sounds to me that it is running lean and hot therefore cycling more than it should and thereby increasing wear on components.

Also, a 1985 myson (velaire?) should have been running a an Inter 10/11 which is what it was designed to use. A different burner such as a sterling 30/40/50 needs to have the same length blast tube, it may need a nozzle/pressure setup to get to a comparable output. If you replace the sterling with a riello (r40/rdb2/rdb2.2 etc)you will have the same problem, do you know if you need a t1,t2,t3 blast tube for instance?

What is the model of myson you have, 40/50, 50/70, 70/90 etc?
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Cliff top
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« Reply #11 on: December 08, 2014, 10:36:51 PM »

Got to admit, I'm not using a gas analyser.  fight. I set the flame so that like a Bunsen burner it appears to burn as hot as possible (most efficient?) , but well away from blowing itself out, so that it wouldn't need to keep igniting. It used very little oil / seemed quite efficient.

From the bookwork, it is a velaire 40\50 and originally had an inter 2000 burner eo11c. Blast tube 81mm. This was changed to the Bentone sterling 35 in 1999.


When I say solenoid, I mean an oil release valve solenoid.
 Start up procedure as far as I can establish with a satronic tf830.3. Power up...fan runs to purge etc. This fan drives a shaft into the oil pump.  ...in the satronic, A current warms a coil round a bimetallic shaft, this moves a slide bar and switch 1 closes...The the ignitor starts running . the coil  current continues and further moves the slide bar until a 2nd switch closes... thus the oil valve opens, releasing pressurised oil up to the nozzle. A flame lights.  The slide bar moves and  a 3rd switch opens, stopping the ignition...   As the cds sensor sees the flame is lit, it  lowers the heater coil current to maintain the slide bar at that position.. If the CDs sensor doesn't work, the coil heats further, the slide bar moves further and trips a lockout condition.. If the flame goes out the slide bar cools/ moves back, closes the open switch and turns the ignition back on. Simple in its way, and very inventive, but prone to the C springs giving trouble when not moved for a long time..

The solenoid appears not to be triggered now, but I haven't had my meter at home to do the basic resistance tests yet to establish why, but as it was OK when last run in march/April, and all 3 controllers exhibit the same symptom, it sort of points to maybe the solenoid coil. (The main coil, not he hold coil).

As a confirmation....From the satronic block diagram, it appears to show trigger switches for the fan,  ignition and oil valve, but no active 'detection' of whether the ignitor is working... Hence it just turns it on\off.....so it doesn't wait to see a spark before releasing the oil, it just assumes it is sparking.   

I can't really say if the ignitor was sparking as the fan noise drowns it out (and the nearby river noise), but the above sequence would seem to mean that if there was no ignition, I would still get an oil spray....which I don't see or smell.....so although it has a bulge, logic says its still working..

QED.
I'm going to drag it off to work Wednesday and check it over on my workbench.
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« Reply #12 on: December 08, 2014, 11:52:59 PM »

I can get a burner fairly close by eye as I've 18 years experience of working on them but the best i've ever got is about 0.5% out in an emergency situation when I've had to do a pump swap and not had my analyser with me. Definitely not recommended however.

A sterling 35 is a fair swap for a inter 11, the other close swap would be an inter b9a/b but still with the satronic/Honeywell tf range as controller. You could try a satronic dko 972 instead of the tf 830/832 as used on late model sterlings fitted to greenstar heatslaves etc. I suspect this would be a better option than changing again to a riello.

The hottest possible flame is not the most efficient. And is not likely to be very good for the boiler either. This is quite easily proven by use of a gas analyser as you have access to efficiency readings as part of the testing process.

A myson velaire should be run with a smoke reading of 1-2 which was common in its day and is an indicator of a relatively poor boiler in terms of efficiency. Today boilers tend to run at 0-1. So if you are trying to run it as hot and clean as possible you really are doing it no favours at all.

Interestingly though, according to my 1985 copy of the manual for that boiler, the 40/50 used the riello mectron 2 which is basically the same as the riello r40 g2 models which are suitable for outputs of 12-30kw. The rdb range are not suitable for output of less than 15kw/51kbtu.

It should be using a 0.40/60 R Monarch (though i'd use a Delavan W or a Danfoss S) nozzle and an oil pressure of 110psi (40k btu), 125psi (45k btu) or 150psi (50k btu)assuming you are on kero. It should be tested at a fgt of approx. 300c and a co2 setting of 10.5% is correct with a smoke number of 1-2.

Not the easiest figures to achieve I would say and definitely need an analyser. I would say that the root cause of all your problems is running too hot. Get a bod in with an analyser and see how it goes over the next 12 months.

Hope this helps, Steve.
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nominous
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« Reply #13 on: December 11, 2014, 09:48:54 AM »

I've disconnected the HP thin oil line to the jet and this blows though ok.  Oil is getting to the pump, ok, and the fan/pump runs just fine. So at this point I suspect the solenoid isn't firing to release the oil.... but for what reason?  I can't find a fault finding flowchart like the Riello one I found last night... (fantastic to have a step by step procedure chart including resistances to check for etc). Maybe the control box doesn't trigger the solenoid until it detects spark?

My Satronic box seems to be doing something similar ??

The ignition comes on before the solenoid. Pretty much right away after asking for a burner start.
Then the unit trips out because there is no flame before the solenoid is triggered.
Once the Satronic has done this once over and been reset, the burner will light up.
Looking at the guide for what is supposed to activate when, I have a fault in the Satronic.
With a well insulated screwdriver, I can manually flip the bottom most contact and it works.
Which gives me the conclusion that the bottom most contacts are slightly bent out of shape.

If I read your post correctly it sounds like you have a similar problem.


Beyond that at present my burner wont self sustain. It's on a bench not firing into a boiler.
But it needs the ignition running al the time in order to sustain the flame and then it's burning very black smoke.
So I've got to investigate the nozzle for a blockage I guess at first.
I've got a pressure gauge on the pump and it's where it's supposed to be according to the manual.
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Cliff top
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« Reply #14 on: December 11, 2014, 11:45:10 AM »

Its worth watching the operation of those switches to see if the solenoid ON click doesn't happen due to a faulty C spring.  Sometimes one cycle is enough to make it start working...hence 2nd go works. I remember tweaking them and re-installing them...which got it back working once. Bought a 2nd box to be more reliable.

I remember stripping my burner jet etc down and it burnt correctly after....though now the bolt is rusted in, so I can't easily get to it this time.
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