Camray 5 boiler switching on by itself

[MMoneypenny]

Hi there,
My first post so apologies in advance.
Just moved into a house with a Camray 5 boiler and even with the thermostat "off" the boiler comes on and the radiators are on. Am having to stop all the oil from being used up by switching the boiler off on the control panel. (The house was empty for 6 months) Any help appreciated,
Many thanks,
M

 

[leakydave]

Is it a combi or a heat-only boiler that heats rads/cylinder?

 

[MMoneypenny]

It is a combo boiler (sorry for not mentioning)

 

[leakydave]

I think the burner will be firing periodically to keep the store warm ready to give you hot water when you need it... the diverter valve must be passing, sending hot water to the radiators. You more than likely need a new valve body, but it could equally be the motor-head stuck in neither one way or the other.

 

[oilhead]

If it is a combi, then if hot water is selected all day or on, then the boiler will fire to maintain the heatstore. If the diverter valve is stuck open, then the boiler will keep firing because the hot water demand is not being satisfied.
The valve can stick physically or electrically. Switch off all power, remove the actuator and try moving the valve stem. It should turn fairly easily. With the actuator off, can you feel resistance to the manual lever? If it is slack, then the motor is probably seized.

 

[MMoneypenny]

Thank you for the info!

 

[Echo the husky]

If it turns out it's not the above, is there a frost stat somewhere, possibly incorrectly adjusted, switching the heating on?

 

[simond]

I don't recall Boulter Camray 5 being available in a combi model. Thought it was a heat-only boiler?

If so, probably stuck zone valve, external to the boiler.

 

[Terrywookfit]

I don't recall Boulter Camray 5 being available in a combi model. Thought it was a heat-only boiler?

If so, probably stuck zone valve, external to the boiler.

You thought wrong then!!