upstairs radiators get warm when the hot water is one.

[cgkstevenson]

I have an old oil-fired Trianco boiler. Separate circuits for CH and HW , no diverter valves anywhere.
Boiler downstairs in kitchen. Hot water tank upstairs in airing cupboard.
Towel radiator in bathroom is part of the hot water heating circuit.
Since last year , radiator on landing now gets warm when the hot water is on but CH is off, likewise other upstairs radiators , though not as warm.
I guess I should check to see if CH pipes out of boiler are warm when the HW is on, so it's down to convection?
Otherwise I can't explain it.

Can anyone out there ?

thanks

 

[StevenJames125]

have you got gravity hot water?

if it's just started happening, and there's no diverter valves, could be an anti gravity valve passing -

 

[cgkstevenson]

Hi , thanks for a quick answer.

Yes , hot water is gravity fed.

But hot water heating is a totally separate circuit. The only place the two circuits come close is in the boiler at the heat exchanger.

???

 

[StevenJames125]

I don't know much about oil fired boilers but where your pump is, is there a valve closely fitted after it?

 

[cgkstevenson]

yes , just above the pump is a manual valve , like a tap. I assume it's there to isolate the pump if it needs replaced.

 

[StevenJames125]

is there 2 of these, one either side of the pump?

 

[cgkstevenson]

yes , If I remember right - which is why I thought they were there to isolate the pump.

 

[StevenJames125]

yes they will be then

after the pump is there no other valve installed on the flow pipework?

 

[cgkstevenson]

Checking this evening - both sets of pipes are hot , though the CH is not on. The hot water is.

Untitled

• cgkstevenson
• 29 Oct 2010
• 1

The pump only has valve at the bottom to isolate the pump.

Untitled

• cgkstevenson
• 29 Oct 2010
• 1

I have the original Trianco TR90 product manual but it doesn't show the heat exchanger in detail and the back of the boiler is very inaccessible.