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My Amtrol hot water maker is throwing er3 - Zone valve? Need diagnose assistance

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clydesdale
clydesdale Member Posts: 85
in Oil Heating

I touch the lever on the zone valve and it is free to swing. The pipes though going into and out of the water tank are not hot. If I then trigger another zone to heat, I then get heat going though the supply and return pipes for the Amtrol hot water maker. I was able to take a "warm" shower. But, it says the water is 102 degrees and the set point is 135. How can I diagnose this and determine if it is the zone valve or whatever else? Thank you.

Comments

  • 109A_5
    109A_5 Member Posts: 4,122

    Since the lever on the zone valve is free to swing, it sound like the thermostat on the indirect water heater is commanding the zone valve to open. However it appears the boiler / circulator is not being commanded to operate. This could be the 'End Switch' in the zone valve is defective, the zone valve is not fully open, a loose wiring connection, if there is a switching relay box between the zone valves and the boiler it could be defective.

    Diagnosis, understanding which electrical controls need to be active for hot water production, visual inspection of the wiring making sure it is all intact, then if needed troubleshooting with a multimeter to find where the call for heat for hot water is being interrupted. Posting pictures of the system may help us help you.

    image.png
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • 109A_5
    109A_5 Member Posts: 4,122
    edited 8:14AM

    Some basic wiring examples. Often systems are a combination of "A" or "B" and a Multi-Zone Relay box.

    image.png image.png
    National - U.S. Gas Boiler 45+ Years Old
    Steam 300 SQ. FT. - EDR 347
    One Pipe System
  • SuperTech
    SuperTech Member Posts: 2,666

    Sounds like a bad end switch on the zone valve, a Honeywell zone valve from your description. This zone valves last about as long as an old light bulb. Best thing to is completely rebuilt the valve and replace the motor. If the valve opens like you described you can see if the end switch is the problem by jumping out the wires attached to the red wires on the zone valve. If the boiler comes on then you know the end switch didn't close when the motor opens the valve.

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