Refleks Stove - Water Circulation

[Dropacog]

Hello All -

 

My 60 foot narrowboat has a Refleks stove with a water coil running through it; it throws out a lot of heat itself - but the water doesn't seem to circulate around the central heating circuit to feed the radiators in the other parts of the boat. I am wondering if an electric pump located somewhere along the water pipes might help?

 

Any thoughts folks? If I'm right in a water pump, what sort of spec. would you suggest.

 

Cheers!

 

David.

[Ex- Member]

If it's not a gravity fed system then yes it needs a pump. Ideally 12 volt with regulated output but they can be expensive a 240 volt smaller sized central heating pump will do the job also.

 

We have a 240 volt Wilo pump

 

http://www.screwfix.com/prods/33590/Plumbi...irculating-Pump

[koukouvagia]

Hello All -

 

My 60 foot narrowboat has a Refleks stove with a water coil running through it; it throws out a lot of heat itself - but the water doesn't seem to circulate around the central heating circuit to feed the radiators in the other parts of the boat. I am wondering if an electric pump located somewhere along the water pipes might help?

 

Any thoughts folks? If I'm right in a water pump, what sort of spec. would you suggest.

 

Cheers!

 

David.

 

A lot will depend on how the pipework is arranged. For example, if it’s a gravity circulation system the rise in the flow pipe needs to be 5 cm per metre. It also depends on how the radiators are configured – ideally they should have a separate flow and return (see http://tinyurl.com/asq6hl ). If it’s not absolutely spot on the results can be disappointing without a pump.

If you fit a 12v circulation pump it should be (according to Refleks) on the return pipe to the stove. There’s a diagram of how Refleks recommend installing central heating here http://tinyurl.com/cylwza (section 9)

Once they're set up correctly they are, IMHO, unbeatable

[boatbodger]

If the pipework CONTINUALLY RISES from the boiler through all the radiators, then falls back continually it's a gravity system and shouldn't need a pump.

 

However even with a pump the radiators can be troublesome to get heat to initially. The Refleks works on the basis of the burner pot being hot enough to vapourise the fuel dripping onto it. When you insert a coil of water into the stove you change the characteristics (the water in the system slows down the rate at which the burner pot will heat up). We installed a refleks about 6 years ago but couldn't get the heat to circulate through the rads properly. Advice from Lockgate Stoves the suppliers was to turn off all the rads except the first one, then once that's hot open the valves to the next one & so in. It worked ! And an expensive item which was about to be thrown into the cut was saved. We had a pump fitted, ours was a 12 volt Brolin pump which only uses about 80mA. I know of someone with a wide beam dutch barge who runs 12 radiators off this pump.

If you've 230v A.C and no shortage of power you could of course use a domestic C.H pump as has been suggested, but such a pump will drain batteries much more than the Brolin.

 

Hope you find this helpful. Bear in mind that these stoves are designed to be left running for long periods, so once you've heat running through the system you can forget about it. not turned on & off daily like a home C.H system.

 

Our system was used to heat the boat during day & evening, then at night we'd switch off all the rads except the bedroom and open the flow into the calorifier to give us a tankful by the morning. Until you're used to their behaviour they can be a bit fiddly to control.

[Dropacog]

Brilliant advice all round! I really, really appreciate it. The power of this forum is awesome! Thanks again, David.

 

Advice from Lockgate Stoves the suppliers was to turn off all the rads except the first one, then once that's hot open the valves to the next one & so in. It worked ! And an expensive item which was about to be thrown into the cut was saved. We had a pump fitted, ours was a 12 volt Brolin pump which only uses about 80mA. I know of someone with a wide beam dutch barge who runs 12 radiators off this pump.

 

Boatbodger - Just to clarify on your top tips, was the need to open the nearest rad. etc. obviated by the pump that you then fitted? Cheers, David.

[boatbodger]

Brilliant advice all round! I really, really appreciate it. The power of this forum is awesome! Thanks again, David.

 

 

 

Boatbodger - Just to clarify on your top tips, was the need to open the nearest rad. etc. obviated by the pump that you then fitted? Cheers, David.

 

 

No David, we already had the pump fitted, the stove seemed to be burning o.k but the radiators wouldn't get hot. By turning off all but 1 radiator, you're reducing the amount of water circulating through the system, thus allowing the water to get hot enough to heat the 1st radiator in the circuit, then when you open the next radiator it will initially cool the system for a while so you have to wait for the heat to build up again, before you can open up the next one and so on. I used to feel thr temperature of the flow pipe out of the boiler. And open the next valve when I reckoned it sufficiently hot, immediately though, one would feel the flow pipe go cooler until the heat built up again.

 

As I said previously I was ready to chuck the whole thing in the water, but first I decided to go and see Mike @ Lockgate Stoves and he it was who described how to get the system working. In his own words "they're a bit touchy feely, till you're used to them. " And I can honestly say his advice worked.

 

Peter.

[koukouvagia]

The Refleks works on the basis of the burner pot being hot enough to vapourise the fuel dripping onto it. When you insert a coil of water into the stove you change the characteristics (the water in the system slows down the rate at which the burner pot will heat up). We installed a refleks about 6 years ago but couldn't get the heat to circulate through the rads properly. Advice from Lockgate Stoves the suppliers was to turn off all the rads except the first one, then once that's hot open the valves to the next one & so in. It worked ! .

 

Funnily enough I employ exactly the same routine when I light the Refleks – i.e. I let the water circulate just round the flow and return pipes until they are very hot then I open the valves to the radiators and the calorifier – but for a different reason. I don’t think it’s got anything to do with the cold water in the system slowing down the rate at which the burner pot will heat up as Boatbodger suggests.

I think it’s got something to do with the efficiency of the pump. The water circulates too fast and doesn’t stay in contact with the fire long enough to compensate for the heat the water gives off as it passes through the radiators. By the time it’s returned to the fire, the water is cold. However, if you turn off the radiators, the water in the flow and return pipes will reach a much higher temperature and will be able to cope with the gradual introduction of cold water into the system from the radiators. The water returning will now be significantly warmer than when it left the fire and radiators get progressively hotter.

I’ve never tried it, but it would be an interesting experiment to add a variable speed control to the pump and have it pumping slowly until the system heated up. Has anybody tried this or is the above reasoning faulty?

[boatbodger]

I don’t think it’s got anything to do with the cold water in the system slowing down the rate at which the burner pot will heat up as Boatbodger suggests.

 

 

 

Hi,

According to Lockgate Stoves the same would apply if there's a pump or on gravity system, suggesting it's not to do with the pump.

 

When I first fitted the refleks I ran it as heater only, without radiators. The way it burnt was considerably different once the wet system was connected.

 

Peter.

[koukouvagia]

I don’t think it’s got anything to do with the cold water in the system slowing down the rate at which the burner pot will heat up as Boatbodger suggests.

 

 

 

Hi,

According to Lockgate Stoves the same would apply if there's a pump or on gravity system, suggesting it's not to do with the pump.

 

When I first fitted the refleks I ran it as heater only, without radiators. The way it burnt was considerably different once the wet system was connected.

 

Peter.

 

 

Interesting. Before I refitted Hampton I had a Refleks running perfectly with a gravity system. I had to fiddle with the starting sequence only when I put a pump in.