Help no CH

[dave215]

I have just replaced my central heating pump as prior to this I had no hot water or heating. i replaced pump with exact Grundoff replacement.
Now I have hot water again but alas no heating.
I imagine the cause of this is that I need a replacement 3 way valve.
Is there anyway of checking this before spending more money.
The pipe leading from the 3 way valve to rads is cold yet if i open bleed valves on rads the water spurts out:::
I can hear pump moving and have bled the pump??
Is there an electrical test I can perform??
there is also a lever of sorts on the side of the 3 way valve what does this do.. problem is that seems hard to reach and seized.
Any advise or tips thanks Dave...

 

[petit_pablo]

problem is that seems hard to reach and seized.

Possibly answered your own question there.
Does the boiler come on in heating only mode?

 

[dave215]

problem is that seems hard to reach and seized.

Possibly answered your own question there.
Does the boiler come on in heating only mode?

The heating system i have has a Potterton boiler and only ever has been able to put hot water on own or hot water and CH

 

[MANDATE]

Sounds very much like your 3 way valve to me, but believe me it is quite complicated.
Could be down to few things. It seems no problem to get the valve to the mid position so room stat is OK. to get valve from mid point to CH position, grey wire to valve must be live. Also the motor within the valve may be the problem. Or the micro switch within the valve may have dirty/burnt contacts so that if valve does move to the correct position there is no output to light the boiler. Or the valve itself may be stuck.
First conform wiring is ok. best thing after that is to see if you can remove the actuator head off the valve spindle. Don't just turn HW and CH to off positon and think there are no live wires there because there is.
With head off you can test spindle for freeness.
If the wiring is OK and the spindle is free your best bet is get a replacement head. (The fault will either be the motor or micro switch).
Suggest you do search on mid position valves.
The lever you mention is for pulling the valve to the mid positon for filling purposes so there is no restriction, it can be held there with a latch.
It has been known on some valves to use this lever if it will far enough to assist the motor and trigger the micro switch to get CH, but it does not cure problems.