Zone valve won’t kick on the pump

richkenny7

Hello,
I recently bought a home with an oil furnace. Many of the pipes on the furnace were bad so I had them replaced, a new transformer installed, and had new thermostat wire ran. (All by an HVAC friend of mine) After the work was done, I noticed an issue with one of my two zones. 

Zone 1 operates normally, but zone 2 will not kick on the pump or the burner. When the thermostat calls for heat, the motor turns, and the valve opens. The pump will only turn on when zone 1 calls for heat. I can tell that zone 2 is properly opening/closing the valve because when I turn on zone 1 to get the pump to turn on, I can feel the zone 2 pipe change temperature as soon as I turn the motor. 

So the motor opens the valve, but won’t kick on the pump. I just tried swapping the motor with a new one but I still have the same problem. My friend claims it is wired correctly, but could this be a wiring issue? Is there anything else that could be causing this? 

Thank you for your time and knowledge! 

Jamie Hall

It not only could be a wiring issue, it is, or a faulty end switch on the zone valve. Check and see if the pump will run with the zone valve end switch contacts jumpered.

STEVEusaPA

Which zone valve do you have.
Power off.
The simple check is to take the wires off the zone valve terminals that are on the end switch. Depending on whether you have a 3 wire zone valve or a 4 wire zone valve.
Connect the 2 wires together.
Power on.
If the burner fires it's the zone valve or the wires powering it. If it doesn't fire the burner, it's the wiring between the zone valve and the aquastat.

richkenny7

@STEVEusaPA its a 4 wire I believe. The other thing I should mention is the motor itself is very very warm. The old motor as well. The valve itself is not warm, but the motor is too hot to touch for more than 5 seconds. 

richkenny7

Ok so I jumped the red wires and the burner did not fire

STEVEusaPA

I hope you didn't jump the red wires on the zone valve but the red wires they were connected to.
Time to trace some wiring. Many times with thick and thin wire under the same wire nut, there's a loose connection, or no connection.
I'm surprised your hvac 'friend' is leaving you hanging.
In the meantime you can take the power leads off, and open it manually. When the other zone calls both will heat up. Until you get it fixed.

richkenny7

I did connect the wires connected to the zone valve. I thought that sounded off. I’ll redo it and connect the right wires. Thank you

EdTheHeaterMan

Different zone valves have different wiring diagrams. Your problem may be incorrect wiring or it could be a defective part. Can you tell if your zone valves look like any of these common valves? If it is not one of these can you post a picture of your zone valves?



Some are easier to understand the wiring than others

richkenny7

Actually, the red wires coming from my zone valve are connected to the red wires on the adjacent zone valve. Both of these wires are connected to thin thermostat wire that runs to the aquastat

richkenny7

@EdTheHeaterMan

richkenny7

I bought the entire zone valve so I have more than just the motor. I could swap the whole head to eliminate the possibility of bad parts. 

STEVEusaPA

richkenny7 said:

Actually, the red wires coming from my zone valve are connected to the red wires on the adjacent zone valve. Both of these wires are connected to thin thermostat wire that runs to the aquastat

If you twisted the 2 wires going to the aquastat together (remove the zone valve wires), and the burner doesn't fire, it's the wiring. If it does fire, it's the zone valve. Because the other zone valve works correctly, I wouldn't think it's the aquastat.
You can also check the 2 leads for the end switch coming off of the zone valve. When powered, you should have continuity (the end switch is closed). If you have continuity, again, it's the wiring or connection between the zone valve and the aquastat.
You can use your meter to check continuity between all the low voltage wiring (power off).

richkenny7

@STEVEusaPA I connected the two wires coming off the aquastat and it fired. 

No continuity on the end switch wires. Is that my problem? Bad end switch?

richkenny7

Ok so I swapped the whole head and problem solved. Thank you very much @STEVEusaPA @EdTheHeaterMan. You guys are amazing for offering your help and knowledge. I shall name my first born Edward Steven!!

HVACNUT

Just swap out the whole actuator since you have it. Put the new motor back in first. Manually lock open both while swapping, aw you have the instructions. 

richkenny7

@HVACNUT that’s what I did and it fixed it. I should’ve done that first, but at least now I learned about end switches and how to test and I know that my old motor is still good so I have a spare. Thanks man!

EdTheHeaterMan

richkenny7 said:

Ok so I swapped the whole head and problem solved. Thank you very much @STEVEusaPA @EdTheHeaterMan. You guys are amazing for offering your help and knowledge. I shall name my first born Edward Steven!!

LOL. Hay Steve... looks like I get first billing 🤪