Hey experts,
When I turn my mastertemp 400 onto spa mode. It will run for about a minute then turn on a HLS error light. After maybe two minutes light will go off and it will go through the same process again.
This issue first started with an E05 error message. I came to this forum to start testing ideas. Opened up my heater and was immediately shocked by how much stuff was inside. And found a nice nest had been built inside. After getting as much debris as possible out I quickly noticed that the stack flue sensor had been chewed through.
So I replaced that, but didn’t solve the cycling issue. I tested the thermal regulator after watching videos on YouTube running it under hot water and it grew also had no corrosion. Today I replaced the high limit sensor but am still having the same issue.
What do I test next? I’m worried it might be the board - but how do I test without investing hundreds on a new one?
Also maybe related:seems the temperature down and pool on button won’t work. I can’t press the pool on button for a reading of the flue stack temperature like I have seen done on here.
When I turn my mastertemp 400 onto spa mode. It will run for about a minute then turn on a HLS error light. After maybe two minutes light will go off and it will go through the same process again.
This issue first started with an E05 error message. I came to this forum to start testing ideas. Opened up my heater and was immediately shocked by how much stuff was inside. And found a nice nest had been built inside. After getting as much debris as possible out I quickly noticed that the stack flue sensor had been chewed through.
So I replaced that, but didn’t solve the cycling issue. I tested the thermal regulator after watching videos on YouTube running it under hot water and it grew also had no corrosion. Today I replaced the high limit sensor but am still having the same issue.
What do I test next? I’m worried it might be the board - but how do I test without investing hundreds on a new one?
Also maybe related:seems the temperature down and pool on button won’t work. I can’t press the pool on button for a reading of the flue stack temperature like I have seen done on here.
