No Hot Water - Combi Boiler

[Tim williams]

Hi

I do not have any hot water but I do have central heating.

I can get the hot water to work if I turn the central heating on and manually move the wheel to the flat position on the hot water dial

also, the immersion heater gives no hot water

 

[moonlight]

What boiler do you have and what is the dial you are turning?

 

[Tim williams]

Hi it is an ideal boiler and tribune tank, the dial is the 2 port motorised valve

 

[moonlight]

I don't think you have a combi if you have a cylinder with an immersion heater, do you have any pictures of the airing cupboard?

 

[Tim williams]

 

[Headrush]

You probably need a new head unit on the motorised valve, you need to check if the valve actually moves when there is DHW demand and if so, check the signel output back to the control box, no movement or no signel output equals new head unit. If there is a 240v supply to the immersion heater, it's possible the overheat cutout has tripped, in which case just reset it and see how it goes, or you may need a new thermostat.

 

[cr0ft]

If you turn the cylinder thermostat up and down do you here it clicking as it passes the temperature of the water in the cylinder? Sounds like that to me, or if not then the motorised valve itself.

 

[Tim williams]

Hi

I will try later today and feedback if I here the clicking, I did change the thermostat over the weekend though so it is a brand new one
If it is the motorised valve why does it work if I move it manually but have to have the heating on?

 

[Tim williams]

just tried it and it clicked

 

[Headrush]

Hi
If it is the motorised valve why does it work if I move it manually but have to have the heating on?

Because there is no electrical signal coming from the DHW valve to activate the pump and boiler, so you are using the CH valve to do the same job..

 

[Tim williams]

ok, so does that mean it is the valve that is broken and needs to be replaced?

 

[Headrush]

... you need to check if the valve actually moves when there is DHW demand and if so, check the signal output back to the control box, no movement or no signal output equals new head unit.

 

[Tim williams]

You probably need a new head unit on the motorised valve, you need to check if the valve actually moves when there is DHW demand and if so, check the signel output back to the control box, no movement or no signel output equals new head unit. If there is a 240v supply to the immersion heater, it's possible the overheat cutout has tripped, in which case just reset it and see how it goes, or you may need a new thermostat.

How so I check if the valve moves or check te signal output?
Also, how do I reset the immersion heater?

 

[Headrush]

I'm talking about the box on top of the valve (the valve head). More often than not it's possible just change the head and not the whole valve.

 

[moonlight]

I had a similar problem and it turned our to be the programmer. Not the valve, but it could be either. Might be worth calling a plumber that is good with the electric side of things or an electrician.

just tried it and it clicked

Did the valve on the hot water side move?

 

[Tim williams]

No, the valve didnt move when I moved the thermostat

 

[moonlight]

It probably is the head then, but still as I said before mine turned out to be the programmer. The head will remove. If you turn the power off remove the head turn the power back on and see if the head moves. While the head is off. Try to turn the pin with your fingers. If it moves freely you can probably just change the head. Sometimes the head smell when they fail.

 

[Tim williams]

thanks all, I will try changing the head and see if that works?

Can someone tell me how to check the Immersion heater and reset it?

 

[moonlight]

If you take off the white top of the immersion you should see a small button that you can push back in. The thing is if this has popped out it is because there is a problem. Check the temperature is not over 65 degrees. Good luck

 

[cr0ft]

If the thermostat clicks then it's getting power to it from the programmer. I reckon it has to be a faulty HW zone valve. You can replace just the head but if the valve itself is getting on a bit best to replace both. Any decent heating engineer should be able to swap it for you.

 

[cr0ft]

Hi

I will try later today and feedback if I here the clicking, I did change the thermostat over the weekend though so it is a brand new one
If it is the motorised valve why does it work if I move it manually but have to have the heating on?

Because either valve will fire the boiler when it motors to fully open. The boiler sees no difference between heating zone valve open and hot water zone valve open. Both just send 230v to the boiler to tell it to fire. When you have heating on it tells the boiler to fire, doesn't matter what hot water zone valve is doing.

Your hot water zone valve isn't motoring over. If we were coming out to do this we'd change the whole valve as last thing I'd want is to swap the motor the. Have the valve go after.

Usually motors fail when the valve is starting to scale up. Put a new motor on an old valve and it's life can be reduced.

 

[Tim williams]

So an update on where I have got to....
The I removed the motorised valve and it smelt burned out so I have order a new one, hopefully this is the problem

the immersion heater had tripped so I reset it, however today we have no hot water again so I checked the trip and it had popped again, any ideas what is causing it to trip out?

 

[ShaunCorbs]

So an update on where I have got to..
The I removed the motorised valve and it smelt burned out so I have order a new one, hopefully this is the problem

the immersion heater had tripped so I reset it, however today we have no hot water again so I checked the trip and it had popped again, any ideas what is causing it to trip out?

Best get a G3 engy to have a look at it,