Hot Water, Too Hot

[norwoodt]

Would appreciate any help or comments on this one, as my inlaws (on Holiday)
Have given me the task of sorting the problem out.

The hot water cylinder is far too hot, and it has effected the central heating (not as warm as it was).

Have tryed adjusting the cylinder thermostat and it apppears to 'click' and be doing something, but not sure?

Basically was wondering if there are any checks i can do, or trial and error tests to locate the source of the problem.

can i test if the T shape valve, is opperating correctly?

Any comments welcome

thank you...

 

[dal5band]

With the H/W stat down, room stat up, there should be some action on the valve. Otherwise suspect valve motor. Check by using manual lever on the side.

 

[JPC]

check the imersion heater is not constantly on ...ie turn it off at the switch if its is on.
as stated cound be ur 3 port valve or us stat.
if u turn on c/h only..the valve should close the water from going into the cylinder...does it ?
can the valve be moved manually ?

 

[norwoodt]

Thank you very much for your responses.

I put the HW stat to min. fired up the Boiler (you can only choose to have the boiler on and off, ie you cant select HW only or CH only) and all three pipes around the valve were hot!

the pipe going into the cylinder should not be hot should it?

The CH is still suffering.

Do i need to replace Honeywell valve (V4073A1039) (five wires), do i drain system to do this?

Cheers

 

[dal5band]

1 Do a manual test just to confirm. - push the lever on the side - it should stop the H/W side. This to make sure the valve itself is ok (i.e. the bit in the water).

2 You do need check it's not just a loose connection or H/W thermostat. It's mains voltages by the way.

I understand you can change just the motor unit (they call it an actuator) on later ones so we need someone on here who knows which type you have.

 

[norwoodt]

at the risk of sounding like a total idiot, not sure how to check for loose connection any tips?

 

[dal5band]

Have a look at waveneygnome's posts above "Y-Plan problem ..." - it looks like the same problem.

 

[ChrisR]

1 Do a manual test just to confirm. - push the lever on the side - it should stop the H/W side.

Oh no it shouldn't. It opens the valve to CH + HW.

I understand you can change just the motor unit (they call it an actuator)

NO, the motor is inside the actuator and separately replaceable.

----

Turn CH on, ie in your case HW thermostat down, CH thermostat up.

Valve should open for CH only, lever on the end should have no resistance.

Then you need to be listening at the valve and either:
turn CH thermostat Down and HW thermostat Up, or
turn off the electricity to the heating system.

You should then hear the valve motor whirr shut, and there will be resistance at the lever.
If not, the wiring's wrong.

The valve takes 20 secs or so to open to CH