I just replace the 3-port motorised valve in my new bungalow (because it was always sending heat to both HW and heating), but now when I turn on any combination of HW or heating none of the three pipes around the 3-port valve are heating up. The boiler seems to fire briefly but then go off. The pump seems to over-run for ages.
What might cause this issue, could it be an air-lock?
I've tried continously bleeding from 1. the cylinder bleed valve, 2. the magnaclean bleed valve & 3. the pump (as per pic below). 1 & 2 work good HOWEVER I can remove the metal (bleed) plug from the pump entirely and no water comes out.
Any suggestions greatly appreciated.
PS: when installing the valve I only half drained the system to get level down to below the 3-port valve and save draining all the radiators also. Not sure if that could have contributed to the problem?
What might cause this issue, could it be an air-lock?
I've tried continously bleeding from 1. the cylinder bleed valve, 2. the magnaclean bleed valve & 3. the pump (as per pic below). 1 & 2 work good HOWEVER I can remove the metal (bleed) plug from the pump entirely and no water comes out.
Any suggestions greatly appreciated.
PS: when installing the valve I only half drained the system to get level down to below the 3-port valve and save draining all the radiators also. Not sure if that could have contributed to the problem?