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Aquastat - no power on the circulation

Techclique
Techclique Member Posts: 3
in Thermostats and Controls
Hi everyone,
My furnace will not start so I did a bit of troubleshooting and think the Aquastat is bad but wanted to check before spending $300. When calling for heat the relay in the aquastat clicks in and buzzes, I have 24VAC on the burner outputs but 0 on the circulator output. Nothing else happens except the relay hum. If I flick the relay the buzzing stops and once I heard another relay deeper in the furnace kick but that was it. I assume I should have 120VAC on the circulator terminals when that relay kicks in indicating a bad board, is this correct?

If I need to replace it how do I find the exact model number, I see it says Honeywell L8148E but searching for a replacement shows another 4 digits. The board has the numbers 9948 stamped on it but they don't seem to be part of the model number. I included a picture in case that helps. Thanks in advance for any advice, I really do appreciate it.


Comments

  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    Those extra four digits are production numbers. You can replace for same or put a Carlin Hydrostat (for gas) in there.

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