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Zone valve trouble

jascosupplyjascosupply Posts: 3Member
I just ran 20 feet of new baseboard in a basement. The home owner had the supply and return already stubbed out for me. It is a 3 floor Home. Basement main floor and top floor. There are two zone valves on the system. And a new thermostat was installed for the basement by his electrician. With the thermostat set at 66 in the basement we are only reaching 62, and the thermostat on the main floor is off and yet it has reached 81. I believe this is because the zone valve for the main floor is defective. And the boiler is trying to satisfy the basements thermostat causing th main floor to over heat and preventing the basement from reaching temperature. Before I change the zone valve I was hoping to get some of your opinions. Thanks in advance
- Matt


  • GroundUpGroundUp Posts: 307Member
    Did you verify that the basement ZV is open when the stat calls? Or disconnect power to the upper level ZV to verify that it's staying open? Sounds to me like it's wired wrong. No reason the lower level isn't heating on a call for heat if the ZV is open
  • jascosupplyjascosupply Posts: 3Member
    No I have not gone back to the job yet. Just getting info from the homeowner. I will try those steps when I get there though. Thanks for your input
  • HVACNUTHVACNUT Posts: 1,582Member
    I'm sure there is but it wasn't mentioned, a seperate zone valve was added for the basement?
    Is the lever on the 1st floor zone valve locked open or is there 24v at the motor?
    Basement zone could be air bound, assuming its wired correctly.
  • jascosupplyjascosupply Posts: 3Member
    The defective zone valve is for the top 2 floors and the other zone valve controls the basement. In the basement there is a 3 foot piece of slant fin 30 that was existing in the entry way and it appears to have been teed off in the ceiling for the stub outs provided too me, in the main room. Which I ran 20 feet of slant fin 30. The switch on the zone valve for the top floors is broken off the gears. It’s loose and slides back and forth with no resistance. It must be stuck open since it’s so hot upstairs. The top floors are heated with steel convector elements inside cabinets. All of which have bleeder valves. I bled the system several times. Maybe I should go at it again in the basement? And fix the zone valve for upstairs? Any other ideas?
    Thanks again guys for your help!
  • GroundUpGroundUp Posts: 307Member
    If you are able to manually close the upstairs ZV, perhaps by removing the head and wrenching the valve closed, all water would be forced through the new element and pushing any trapped air through. I recently had a similar issue with some new element in a basement being airlocked even with a dedicated zone circ. If the basement is not heating, you're not getting flow. If you're not getting flow to the basement with both ZV open, there is either air in the system, incorrect piping, or an undersized circ the way I'm picturing it in my noggin.
  • HVACNUTHVACNUT Posts: 1,582Member
    If the lever moves freely, it sounds like it's got 24v to it. Check the wiring. Is the basement zone valve open?
  • Big Ed_4Big Ed_4 Posts: 1,094Member
    Basement is calling for heat and nothing , now upstairs is over heating ... The electrician wired the zones up .. Hmmmmm :).
    I have enough experience to know , that I dont know it all
  • Big Ed_4Big Ed_4 Posts: 1,094Member
    The thermostats are wired to the wrong zone......
    I have enough experience to know , that I dont know it all
  • newagedawnnewagedawn Posts: 549Member
    sounds like an electrical issue and did you purge the heat loop?
    "The bitter taste of a poor install lasts far longer than the JOY of the lowest price"
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