no hot water or heating together

[jamestyler]

I don't know if anyone can help me, who may have come across this problem before?

This started to happen about a month ago:

i have a gloworn boiler and my system is open, i have 2 tanks in the loft space.

i can get heating ok and hot water ok, but when both are on together i only get hot water. i am having to use my immersion heater for hot water in the evenings and morning as the radiators do not warm up otherwise if i have hot water programmed on too.

there is also a little bit of noise which is coming from the pipes when the hot water is on, maybe this is trapped air?

what is causing this problem as it is condusing me?

 

[Aquaheat]

It could be one of three things,

Either a faulty programmer

or a faulty mid position valve

or a faulty cylinder stat.

Have you noticed that the hot water is hotter than usual?

 

[jamestyler]

hmmm

ok

i do have a 3 port valve but it seems to work (i mean move across) as the heating comes on, and the hot water comes on (rest position this is i believe).

the cylinder stat? how would that cause this problem though....

the programmer also seems to be fine as we get them both separately....

 

[Agile]

But does the valve move to the mid position when you select both?

It could also be a weak pump but that tends to show up unbalanced rads.

Tony

 

[Aquaheat]

If the cylinder stat does not send the signal to close then that could be the fault.

As Tony said:

But does the valve move to the mid position when you select both?

That is why the question was asked

 

[dotto]

If the cylinder stat does not send the signal to close then that could be the fault.

As Tony said:

But does the valve move to the mid position when you select both?

That is why the question was asked

Or you probably have a diverter valve with hot water priority instead of a mid position valve.