heating comes on when HW only is selected

[electricdave]

Hi,
Please can anyone help.I have a heating system with a Honeywell mid-position valve (V 4073A).When hot water only is selected the central heating comes on as well.I suspect the valve is faulty.Does anyone have wiring diagram of theINTERNAL wiring of the valve?
Regards
Dave

 

[gas4you]

Forget the wiring, it sounds as if the valve body has stuck mid position.

 

[electricdave]

HI,
THJanks for reply.I should have said the valve works ok when CH or CH and hot water ere selected.Just a problem wheh HW only is selected.
Regards
Dave

 

[seco services]

maybe the port has abit of crud blocking it from shutting.
the paddle is faulty
spring is weak.

 

[electricdave]

Hi'
Thanks for reply
Regards
Dave

 

[kevindgas]

just replace it with a drayton valve, when it sticks again you can take the head off and free up the valve. it also has a small indicator on the side so you can see exactly what position it is in

 

[electricdave]

Hi,Kevingas,
Thanks for reply.Will do as you say.
Regards
Dave