radiators on with thermostat right down/ 'hot water only' on

[Laura78]

Hi
I know very little about plumbing but we have the problem as listed in the subject heading. A plumber came today and stomped around the house saying the problem was likely with a valve and where was the pump? We don't appear to have a pump, can't find one, hear one, or ever seen one in the house. Our boiler is quite old (too old to get a maintenance contract with eg british gas). So in the end the plumber left and said ring him when i'd found the pump.
I know some water systems are gravity driven without a pump, if this is the case with us, where is the problem likely to be? I am happy to accept I may not be able to fix it, but I would like to know what i am talking about if/when we get a plumber back so as to prevent the above scenario again.
thankyou
Laura

 

[tryitandsee]

Only offering scant ideas from the little information given about your system. Sounds like your motorised valve (if you have one) is stuck/not working and allowing the heated water to go through the central heating circuit.

Look on the FAQ at front for info.

Gravity systems as I understand them, would only heat the hot water and may be a few rads upstairs , but a pump would be necessary to push the water round the downstairs rads. Keep looking.

 

[DCPlumbing]

The plumber was probably stomping around your house looking for your airing cupboard where he would expect to find your pump and zone valve(s). As tryitandsee said the problem is more than likely a motorised (zone) valve fault.

In some cases on older systems the pump could have been installed under the floorboards. I was actually reading a thread earlier this evening where someone was asking for advice on how to cut a hole in their laminate floor to gain access to the heating pump.

Best of luck!

 

[Laura78]

thanks for the replies. The airing cupboard is easy to find, but there is no pump in there. i suppose it must be under the floorboards between the tank and the boiler (tank directly above boiler). This is not a big house, there is nowhere else it could be! I have studied the faqs in depth, now i know what a motorized valve looks like but i still can't find it. I guess the floorboards may be coming up- would you agree this should be the next step?

 

[andytheplumber]

Where is the boiler situated if its a back boiler sometimes its under the floor near the boiler.

 

[Laura78]

the boiler is at head height mounted on the kitchen wall

 

[ollski]

I would hazard a guess he was looking for the anti gravity valve although I don't really know why he would have needed to find the old one. If you have some details about the boiler we may be able to hazard a guess.
Very little is too old to go on a bg maintenance contract by the way!

 

[Laura78]

the boiler is a Thorne Apollo...any help?

 

[twgas]

thorn apollo wil definately have a pump and nearly always a motorised valve. looks like a few floorboards will be coming up, unless you have a false ceiling!

 

[Laura78]

Thanks for all your advice, at least now I have a better idea of what's what.
Laura

 

[tryitandsee]

Follow the hot pipes from the boiler in kitchen, that will lead you to the pump.

My central heating pipes travel down from the boiler and the pump is located in the side/back of kitchen unit, I had to cut a large hole inside unit to gain access to the pump. If house was sold, new occupier would not find it