navitron
 
Renewable Energy and Sustainability Forum
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Anyone wishing to register as a new member on the forum is strongly recommended to use a "proper" email address - following recent spam/hack attempts on the forum, all security is set to "high", and "disposable" email addresses like Gmail, Yahoo and Hotmail tend to be viewed with suspicion, and the application rejected if there is any doubt whatsoever
 
Recent Articles: Navitron Partners With Solax to Help Create A More Sustainable Future | Navitron Calls for Increased Carbon Footprint Reduction In Light of Earth Overshoot Day | A plea from The David School - Issue 18
   Home   Help Search Login Register  
Pages: [1] 2 3   Go Down
  Print  
Author Topic: immersion accelerator tube  (Read 7844 times)
mikegally
Newbie
*
Offline Offline

Posts: 37


Norfolk and Chance


« on: April 17, 2014, 10:31:11 PM »

Hi all,

I have a 40inch copper tank with a 36inch top entry immersion, the thermostat is 18inch which results in only a third of a tank of hot water. I have the solar iboost diverting my surplus energy into the immersion and ideally I would like to heat the whole tank or the majority of it if possible.
I have read a few posts about an accelerator tube and theoretically it sounds viable but has anyone actually successfully made one ? If so I have a few Q's -

1. What did you use to make it.
2. Should it be fixed to the element or can it be loose resulting in it sliding down and sitting on the bottom of the tank.
3. What diameter tube is best, my immersion is approx 40mm in diameter.
4. How long should it be based on my set-up.

Any pics or diagrams would be great...or any help at all.

Kind regards,
Mike
« Last Edit: April 19, 2014, 08:43:16 AM by mikegally » Logged

never say never
dhaslam
Hero Member
*****
Offline Offline

Posts: 6775



« Reply #1 on: April 17, 2014, 10:39:21 PM »

Haven't made one but  it cannot sit on the bottom of the tank  without allowing  water to enter the tube at the  lower sides.
Logged

DHW 250 litre cylinder  60 X 47mm tubes
Heating  180,000 litre straw insulated seasonal store, 90X58mm tubes + 7 sqm flat collectors, 1 kW VAWT, 3 kW heatpump plus Walltherm gasifying stove
mikegally
Newbie
*
Offline Offline

Posts: 37


Norfolk and Chance


« Reply #2 on: April 17, 2014, 10:43:40 PM »

Haven't made one but  it cannot sit on the bottom of the tank  without allowing  water to enter the tube at the  lower sides.
Yeah thanks, people talk about cutting out some access holes in the bottom and top of the tube to assist the flow.
Logged

never say never
solar_cambridge
Sr. Member
****
Offline Offline

Posts: 382


« Reply #3 on: April 17, 2014, 10:53:03 PM »

I think about 6 months ago someone posted on here that they were making one from stainless steel pipe. Not sure they ever posted back on the results.

Did you read the thread last week about an alternative suggestion of mounting a 600watt element on an external pipe.
Logged
mikegally
Newbie
*
Offline Offline

Posts: 37


Norfolk and Chance


« Reply #4 on: April 17, 2014, 11:31:27 PM »



this is the only image I can find of an actual DIY job, I think this was the stainless steel project from last year.

I'm committed to giving an accelerator tube a go, I was hoping for a steer before I have a go myself.

Mike
Logged

never say never
gravelld
Hero Member
*****
Offline Offline

Posts: 556


« Reply #5 on: April 18, 2014, 08:50:12 AM »

I thought the accelerator tube was for side entry immersions toward the top of the tank? Otherwise, how would the inlet and outlet work against stratification when they protrude horizontally?
Logged
Mostie
Sr. Member
****
Offline Offline

Posts: 495



« Reply #6 on: April 18, 2014, 12:28:51 PM »

try a circulating pump on the tank with a non-return valve
Logged

2x Solis PV = 1.875 kW, Mitsubishi inverter heat pump. Yorkshire Boiler Stove.
todthedog
Global Moderator
Hero Member
*****
Offline Offline

Posts: 4204



« Reply #7 on: April 18, 2014, 05:21:52 PM »

What ho
Have a look at this thread and whattever 's post and diagram
http://www.navitron.org.uk/forum/index.php/topic,22482.msg262153/topicseen.html#msg262153
Logged

'In a time of universal deceit, telling the truth is a revolutionary act'
Stochengberge
Sr. Member
****
Offline Offline

Posts: 486



« Reply #8 on: April 18, 2014, 07:49:09 PM »

Surely a de-strat pump has got to be easier? Out the top, into the bottom, run via a cylinder stat. Cylinder gets hot, pump runs, gradually cooling the contents, pump switches off until the cylinder is back up to temperature. It has only got to be a small flow.
Grundfos do the dinky little Bronze one for just this sort of job, but even that may need throttling back a bit.

SB.
Logged

On the North Downs of Kent with 3.2kWp facing 12' west of south @ 33', 36 x 58mm Thermal tubes on an east / west split, 300ltr triple coil DHWC and an 8kW to water WBS.
geoffus
Jr. Member
**
Offline Offline

Posts: 74


« Reply #9 on: April 18, 2014, 09:30:13 PM »



this is the only image I can find of an actual DIY job, I think this was the stainless steel project from last year.

I'm committed to giving an accelerator tube a go, I was hoping for a steer before I have a go myself.

Mike


Hi, it was me who was going to try the accelerator tube, I didn't actually complete the project in the end, as although thought it a great idea and cost nothing to run and be self maintaining using simple physics,  I bought a 36" 3kw element instead. I fitted the element and turned the thermostat past the stop to around 80c,

I then fitted a new tank stat strapped 1/4 of the way from the top of the tank and used that as a failsafe device,

it was set at just over 80c initially and was easily adjustable to get the maximum heat into the tank without getting dangerously too hot, the tank stat was wired in series with the immersion stat so if one failed the other would cut the heat.
Using a SolarImmersion device the tank can take up to 6-7 Kwh on a good day,

this gives me enough for my needs with a modern foam insulated tank and 4 extra immersion jackets. Its still plenty warm enough for showers in the morning and has the rest of the day to heat up again, the tank stat for the gas boiler is set to low around 45 deg c to boost when only needed.








Logged
mikegally
Newbie
*
Offline Offline

Posts: 37


Norfolk and Chance


« Reply #10 on: April 18, 2014, 09:59:12 PM »

Thanks guys,

lots of good options recommended but Ive decided to try the accelerator tube.

I have considered all other options over the last few months ( willis, destrat pump, custom immersion) but they all require plumbing, modification and/or expense (pumps, copper pipe, fittings, radiator element, valves etc etc).
I have priced a 1m length of 2" stainless steel pipe, 15 and that's the only cost, no mods or pipework to worry about.....apart from everything else i'm really interested to see if the theory of an accelerator tube will actually work in a simple domestic set-up.

If it works it will be very cheap and effective with virtually nothing to go wrong or maintain once its up and running.

Ill take some pics and post the results again when I'm done in a week or two......in the meantime I'm still interested to hear about anyone else's experience.

regards,

Mike
Logged

never say never
ecogeorge
Hero Member
*****
Offline Offline

Posts: 1295


« Reply #11 on: April 18, 2014, 10:14:00 PM »

Mike , I can find you some ss tube (52mm OD) for the cost off postage if it helps.
PM if interested.

George.
Logged
mikegally
Newbie
*
Offline Offline

Posts: 37


Norfolk and Chance


« Reply #12 on: April 18, 2014, 11:18:44 PM »

Mike , I can find you some ss tube (52mm OD) for the cost off postage if it helps.
PM if interested.

George.


Thanks George, pm sent
Logged

never say never
mikegally
Newbie
*
Offline Offline

Posts: 37


Norfolk and Chance


« Reply #13 on: April 18, 2014, 11:24:35 PM »

this gives me enough for my needs with a modern foam insulated tank and 4 extra immersion jackets. Its still plenty warm enough for showers in the morning and has the rest of the day to heat up again, the tank stat for the gas boiler is set to low around 45 deg c to boost when only needed.



Hi Geoffus, thanks for the reply, Ill let you know how it goes,

Mike
Logged

never say never
crivvens
Newbie
*
Offline Offline

Posts: 21



« Reply #14 on: April 21, 2014, 04:37:18 PM »

I tried this with a plastic  2" pipe so it would go through the immersion hole. I left 6" gap at the top to allow circulation It works wonderfully if the sun is constant with early hot water available. However when the cloud came along circulation stopped and the thermostat was tempted to cut in. So on average I had less hot water than without the sleeve. A metal sleeve may have helped a bit. I ended up pumping water from bottom to the top to ensure as much hot water as possible.
Logged

2.1kWp solar PV system, Owl Intuition PV/C + Raspberry Pi monitoring, Solarimmersion for hot water.
Pages: [1] 2 3   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.20 | SMF © 2013, Simple Machines
SMFAds for Free Forums
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!