Hot water too hot and pump not cutting out

[OllyJC]

The hot water from our gas fired central heating system has in the past week got very hot.

Also, the central heating pump continues to operate after the timer has switched off the hot water and central heating. The boiler is also continuing to heat the hot water after this is 'off'. Whilst the pump is still wirring, the radiators do not continue to heat when the heating is off.

I have replaced the hot water cylinder thermostat and this has made no difference ( one wire is blue, the other brown ans a green/yellow earth wire is not needed on the new Honeywell thermostat. I assume that it doesn't make a difference which way the two wires are connected to the thermostat - as long as the first two connections are used as shown in the instructions?)

It has been suggested that it might be the two/tree way valve - any ideas?

 

[seco services]

if you have two of these

i would say the hw one is sticking open

 

[OllyJC]

There are two of those. Presumably it needs replacing rather than repair?

 

[seco services]

on the hw one check the lever on the end has it got resistance or is it loose.

 

[OllyJC]

Not sure which one is the hot water one, but both levers are faily loose.

 

[seco services]

is this with the programer off on both heating/hw ?

 

[OllyJC]

At the moment, the boiler is switched off at the main switch and only turned on when we need heating in the evening and early morning. Otherwise, it is firing continually.

 

[seco services]

if all is switched off both levers should have resistance on them when you push them across then when you let go you should hear the valve move back.
if the levers are loose and no resistance the valve is open.

 

[OllyJC]

Ok. Thanks. I'll look at replacing this.