Stove Burner Query

[cooket3]

Hi

When I have my multi burner stove on at a high temperature the water gets hot and circulates upstairs via a gravity feed (Pipe 1 in the attached image, this pipe gets really hot, this is fine. I turn the pump on (P) in my image attached, and the water is circulated through my house, this is still fine.

However when I turn the pump off when the stove is still hot, pipe 1 becomes stone cold and pipe 3 (feed from upstairs return im assuming) gets very hot as if the water is falling back down and reversing the original pump flow. After a while the pipes start banking as if boiling water is in the back boiler and is forced up pipe 1 (I know it does as ive had my hand on it when it was stone cold, then bang, boiling water went up and burned my hand!)

I do not understand why when the pump is turned off the water flow suddenly gets reversed. And even against the natural hot water goes up convection. Makes me wonder if my pipes are all wrong.

The fire and pipes were fitted before I moved in. I also have other queries, which ill post seperately.

In the image attached im assuming pipes

1: goes upstairs to the radiators and coils through the hot water tank to provide some heat there, then returns in pipe 3

Pipe 2 must be the downstairs feed

Thank You for any help you can provide

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• cooket3
• 15 Oct 2012
• 1

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• cooket3
• 15 Oct 2012
• 1

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• cooket3
• 8 Jan 2013
• 1

 

[dcawkwell]

1. The pump is installed incorrectly vertical.

2. Check the the arrow on the pump is pointing to the stove.
If not it is the wrong way around. The pump looks to be on the return
to the stove which is ok. Make sure it is pumping into the stove.

 

[cooket3]

Hi Thanks for the reply. Yes the arrow is pointing towards the stove.

When you day the pump is verticle, do you mean the whole unit or the way it is facing, therefore just needs rotating?

Thanks again

 

[dcawkwell]

Hi Thanks for the reply. Yes the arrow is pointing towards the stove.

When you day the pump is verticle, do you mean the whole unit or the way it is facing, therefore just needs rotating?

Thanks again

Yes needs rotating so it is horizontal or closer to horizontal.

 

[dcawkwell]

I am guessing that when the stove is hot with no pump on and pipe 1 is hot there is actually no circulation going on via this pipe due to a down leg or something and the water is just getting very hot up to there.

When the pump is running all is fine and it is circulating.

You then switch the pump off and the boiler then heats the water rapidly and you get the kettling.

There is a fault on the gravity pipes it must be a continuous flow upwards.
No down legs. I would suggest putting the pump on a pipe thermostat so that when the pipes are hot the pump circulates.

 

[cooket3]

Yes the top pipe, pipe 1 gets very hot . The radiators upstairs get very hot too and so does the pipes leading into the hot water tank

 

[Onetap]

Who installed it?

Can you get them back to rectify the problem?

Is there an open vent on the system? It sounds like the system is air-locking when hot, due to trapped steam or air, and this is stopping the circulation.

Are there heat dump radiators and/or a hot water storage cylinder upstairs?
The gravity circulation to the cylinder will slow down and stop working as the cylinder gets hotter; there needs to be something upstairs removing heat from the hot flow water from the boiler for the gravity circulation to carry on working.

 

[cooket3]

Who installed it?

Can you get them back to rectify the problem?

Is there an open vent on the system? It sounds like the system is air-locking when hot, due to trapped steam or air, and this is stopping the circulation.

Are there heat dump radiators and/or a hot water storage cylinder upstairs?
The gravity circulation to the cylinder will slow down and stop working as the cylinder gets hotter; there needs to be something upstairs removing heat from the hot flow water from the boiler for the gravity circulation to carry on working.

Hi

I have no idea who installed it

There is a vent - open pipe on the end of pipe 1, which leads back into the radiator tank in the attic for if the water boils - is this what you mean?

I imagine the heat dump radiators are ones up stairs, which do not require a pump to work