I have 2 zone heat- Hot Water baseboard up and down-typical bi-Level.

My downstairs thermostat calls for heat but the boiler will not turn on. I replaced the power motor in the Honeywell V8043-1012 zone Valve- Still no heat- the lever now works as it slowly goes back to AUTO when I move it over to Manual ( NOT LOCKED)
* Tested the Thermostat etc- It's OK*

I had it locked in MANUAL for about 5 days before I put the new power motor in this past Saturday so I had heat from the other zone when it came on for upstairs and the hot water flowed into the downstairs baseboard also.

I also had a water pressure build up to 30/32 psi + and I had excessive steam from the over flow pipe etc. I had to keep opening the pressure valve, plus I bled the lines with a hose attachment to try and get any air etc out and got it back to normal 18/20/psi.


I don't know if the manual lock caused this or not?


* I'm going to probably have to replace the entire Valve ( maybe it's a bad end-switch?) but before I can do this, I need to know is it OK to keep this valve in the MANUAL LOCK position until I can replace it?*

Thanks for any help.

If you lock it open & disconnect the wiring, that zone will heat anytime the other zone calls. By leaving the thermostat wires connected, the lever will probably return to auto anytime the stat calls for heat & is then satisfied. If you leave the end switch connected, the circulator will run all the time.

You can replace the entire power head without having to replace the valve body. It is usually cheaper to buy a whole valve instead of just the power head but you can take it apart & just use the head.