Heating Pump Continuous

Canucklehead

Syerston_HQ wrote: »

The problem(s) aren't sorted. Not sure what to do. The white valve at the back I have seen working, not the one at the front. Can I test these? If so how? Tried to post a photo but no luck. This link might work, take the space out from after the first h.

http://i636.photobucket.com/albums/uu84/martinbhtbf/PICT1946.jpg

HI

Is that a Honeywell or a Tower valve?
230 volts to the sync motor, if yes and the motor is not opening (manual lever moves freely in the slot when open) replace the motor.If you are not sure about using a meter to test electrics get someone in. Most importantly take care.
It would help if the valve was sitting upright. If you are confident you could loosen the nuts and turn it.

GSR

Syerston_HQ

Thanks for taking an interest. I've turned the valve, taken off the cover and stuck in the multimeter. Zero volts between orange and grey, and zero between blue and blue. Manual lever moves freely.
h ttp://i636.photobucket.com/albums/uu84/martinbhtbf/PICT1960.jpg
Any clues?

albyota

with the programmer on, there should be 240v between grey and Blue /neutral.
with the room stat calling for heat, you should have 240v across brown and blue/neutral. the motor should run and open valve.
when fully open you should get 240v between orange and blue. orange sends feed to boiler and pump. however some pumps are connected to the boiler and run on for a few minutes.

albyota

Sorry.....just looked at the original photo... the valve you have taken apart is the hot water circuit so substitute room stat with tank stat.....

Syerston_HQ

Problem has gone away by replacement of the motor valve head. He's my understanding of the problem.
The motorised valve failed somehow allowing 240V to the pump. The cylinder stat was being ignored and the tank was being heated to boiler stat temperature, set at or near max. The boiler never got the message that the cylinder was hot enough and kept the pump running. The boiler fired up for short periods to keep it topped up at 65-70 degrees. This explains why I couldn't lower the temperature of the hot water coming from the taps. I don't know why the pump stopped for 2 or 3 seconds every couple of minutes but frankly I don't need to know. Replacement of motor cost £51 and was easy. Just make a note of which wire goes where and wire up the same. I ended up with a spare white wire but it's not needed with my system. The PCB I got in error cost £100 and sold for £75, both times on ebay.
Thanks to all who helped.