hot water working heating not

[1987]

hi recently my heating stopped working. if i turned on the hot water the radiators would get warm until the hot water was completely heated. but if we turn the hot water of and use it all for say a bath and leave the system for a day and turn the heating on it will come on until we turn the hot water back on again we got a plumber out who thought it was our central heating thermostat tried changing this with no positive result we have since also been told it was the pump which the plumber has changed with no result. he is now saying it is a cyclinder stat wiring problem does this sound right or is it more likely to be the three way valve ?

this is a fairly newish system in a 3 year old house the boiler is ideal and the digital system on the wall is a siemens system.

hope this makes sense

any thoughts appreciated

 

[Hugh Jaleak]

My first port of call would be to check the motorised valve.

 

[seco services]

the posts abit confusing but as said i would check the valve first.

 

[1987]

thanks i no its a bit confusing they way ive wrote it.

my plumber is adamant it is a wiring problem on the cyclinder stat and on researching it all points to the 3 way valve which it appears that would be your first point of call to. The valve moves across ok manually but doesn't seem to kick the heating all the times but sometimes it does would this point to the motor inside the valve been broke ?

 

[Hugh Jaleak]

What make is the valve. Some can be troublesome after a few years use... I'd want to check voltages before condemning the valve, but you need to be competant with a multimeter, otherwise you get bitten....

 

[seco services]

if the valve motors across it points to a faulty micro switch.
check your getting 230v on the orange wire if not operate the m/switch with a screwdriver and see if you get 230v on orange.

maybe the valve is sticky and not fully making the m/switch.

 

[1987]

the plumber checked all the relevant voltages and said they were 240v

if it was just the valve been sticky does that mean it needs replacing or would simply wd40 do the trick ?

 

[Hugh Jaleak]

Make of Valve? If its a Sunvic, my advice is replace it.

 

[1987]

what make valve would you recommend buying not to sure on the make we curretly have

 

[seco services]

honeywell

 

[Hugh Jaleak]

Honeywell. (May be a few £ more, but you get what you pay for IMO.)

 

[1987]

thanks i will give it a go tomorrow see if the changing of the valves solves the problem worth a try

 

[Hugh Jaleak]

Fingers crossed! Let us know how you get on. If you need further advice come back, someone will try and help.

 

[1987]

the valve is a siemens after taking it of and finding the make

 

[1987]

are we best replacing the motor or the valve ?