Central Heating Behaving strangely

[Remoh1]

Boiler is a Glow Worm 18hxi

Controller is Drayton Tempus 7

Wireless room stat is Drayton Digistat RF


first thing in the morning everything works fine heating comes on rads get hot, hot water heats up.

During the day / evening the radiators have stopped getting hot

when I check the system
the wall stat shows the flame saying its telling the heating to be on
The wall stat receiver shows a green light indicating heating on
The controller shows a red light indicating the heating is on

however if the hot water is off the the pump doesnt run and the boiler is off despite the fact all other indicators show that the boiler should be on and the pump should be pumping

anyone got any clues?

it was all working fine up untill about a week ago and nothing has been changed on the system.

thanks.
Richard

 

[gas4you]

Check your zone valve/s

 

[Soggy_weetabix]

and replace the battery in your room stat and re-configure with the wire-less receiver

Dave

 

[Remoh1]

I only have stat valves on the upstairs rads and have set them all to max and the room stat has new batteries in it that were put in 3 days ago and the system reconfigured

any other ideas?

 

[gas4you]

Have you got a cylinder stat? If so what does this control?

If you have one could be the cyl stat faulty.

 

[bengasman]

turn up cylinder stat to 70 and set your dhw override to 'on' when rads get cold and see if they are hot again after half an hour, or open the diverter or zone valves manually whilst

 

[Remoh1]

Have you got a cylinder stat? If so what does this control?

If you have one could be the cyl stat faulty.

I have got a cylinder stat which controls the hot water.

at the moment I have to set the hot water on and the cylinder stat high enough to get the boiler going then on the three way valve I have to lock it over so that the watwer circulates round the heathing system.

the signal gets from the room stat to the receiver in the airing cupboard which switches to heating on but the boiler and pump dont get switched on

 

[gas4you]

at the moment I have to set the hot water on and the cylinder stat high enough to get the boiler going then on the three way valve I have to lock it over so that the watwer circulates round the heathing system.

You have got a zone valve then. Why did you say you didn't have

the signal gets from the room stat to the receiver in the airing cupboard which switches to heating on but the boiler and pump dont get switched on

Replace the 3 port valve head.

 

[Remoh1]

at the moment I have to set the hot water on and the cylinder stat high enough to get the boiler going then on the three way valve I have to lock it over so that the watwer circulates round the heathing system.

You have got a zone valve then. Why did you say you didn't have

the signal gets from the room stat to the receiver in the airing cupboard which switches to heating on but the boiler and pump dont get switched on

Replace the 3 port valve head.

apologies for being thick but is a zone valve and a 3 port valve head the same thing?


if so the 3 way valve has been replaced twice in the last 3 years, is this normal?

 

[Remoh1]

at the moment I have to set the hot water on and the cylinder stat high enough to get the boiler going then on the three way valve I have to lock it over so that the watwer circulates round the heathing system.

You have got a zone valve then. Why did you say you didn't have

the signal gets from the room stat to the receiver in the airing cupboard which switches to heating on but the boiler and pump dont get switched on

Replace the 3 port valve head.

does the 3 port valve head activate the pump and boiler then?

 

[MANDATE]

It certainly does when central heating is called for without HW or the hot water has been satisfied.

 

[Remoh1]

It certainly does when central heating is called for without HW or the hot water has been satisfied.

so its that valve that turns the pump and boiler on and not the controller clock?

please dont roll your eyes at me cause I dont understand cntral heating, if I understood it I would be answering questions not asking them

 

[dal5band]

The sequesnce is something like this :

clock CH on - room stat on (radio) - stat receiver on - valve opens to CH and gives on signal to - boiler & pump on.

in parallel
clock HW on- cylinder stat on - valve opens to HW and gives on signal to - boiler& pump on.

Looks like the CH chain of command is failing near the valve. If you are having to open the valve manually to CH, then looks like the valve is not working to CH. Before changing the valve, you need to confirm that it is getting the on signal - i.e. it is not just a loose connection somewhere.

 

[Remoh1]

thank you for the detailed reply

I was just struggling to get my head around the fact the 3rd 3 port valve had failed in as many years. cant they make one that will last ffs.

I will get a torch in the cupboard tomorrow and check all the conections is it possible to replace the motor part of the valve without having to remove the water pipes? may be a dumb question but I'm a programme manager not a heating engineer, if anyone needs hosting for their own website or needs a website setting up then please feel free to pm me and I am more thean willing to help.

 

[bengasman]

in the mean time, have a look at FAQ, it will give you some interesting insights