Mastertemp 400 heats fine until temperature gets to about 86-88 degrees and then starts cycling with the HLS led lit.
- Replaced HLS and Thermal Regulator (aftermarket- opens at about 130 degrees) in February 2023. >> Problem went away for a month or so and is now back.
- Ran heater w/o thermal regulator to test and >> No HLS cycling.
- Checked manifold bypass valve / spring >> They're both intact.
Anything else I can check? Is it possible for a Thermal Regulator to go bad in just a few months?
Thanks for the help!
- Replaced HLS and Thermal Regulator (aftermarket- opens at about 130 degrees) in February 2023. >> Problem went away for a month or so and is now back.
- Ran heater w/o thermal regulator to test and >> No HLS cycling.
- Checked manifold bypass valve / spring >> They're both intact.
Anything else I can check? Is it possible for a Thermal Regulator to go bad in just a few months?
Thanks for the help!
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