Hello TFP experts.
I have Mastertemp 400 that's about 5 years old. I have attempted a a deep dive search here and found a few threads that very similar.
Purchased and installed new AGS switch from Amazon. Didn't fix it. Also at the same time, I replaced the thermal regulator. (tested old one and new one in hot water, both worked)
On the header, I noticed the bottom 2 bolts were rusted(plan on changing them all to stainless). Removed the 2 to see if any water game out. No water came out. Ended up keeping going. Removed the header completely so that I could check the Manifold Bypass Valve. Looked good. Copper on the heat exchanger pipes in and out looked good. Thermister and HLS looked good, but I haven't tested them. I haven't replaced the control board yet since it's pricey. Really don't wanna jump into the tub yet, since its a big job. Honestly don't wanna just replace everything in hopes to find a needle in a haystack.
What are some other tests I can run? I'm good with DVOMs, resistance checks etc.
Not sure where to do at the moment. Suggestions?
Video added:
Maybe one of the GURUS can help?: @JamesW @Arizonarob @ps0303
I have Mastertemp 400 that's about 5 years old. I have attempted a a deep dive search here and found a few threads that very similar.
- MasterTemp 400 Heater won't stay running, but it was never confirmed if a new control board solved the problem?
- Mastertemp 400 - Burner shuts off, AGS and SERVICE HEATER lights
- Cleaned filter to ensure proper water flow
- Temp was set to 102
- Revision 13
- Thermister reporting ambient temp
Purchased and installed new AGS switch from Amazon. Didn't fix it. Also at the same time, I replaced the thermal regulator. (tested old one and new one in hot water, both worked)
On the header, I noticed the bottom 2 bolts were rusted(plan on changing them all to stainless). Removed the 2 to see if any water game out. No water came out. Ended up keeping going. Removed the header completely so that I could check the Manifold Bypass Valve. Looked good. Copper on the heat exchanger pipes in and out looked good. Thermister and HLS looked good, but I haven't tested them. I haven't replaced the control board yet since it's pricey. Really don't wanna jump into the tub yet, since its a big job. Honestly don't wanna just replace everything in hopes to find a needle in a haystack.
What are some other tests I can run? I'm good with DVOMs, resistance checks etc.
Not sure where to do at the moment. Suggestions?
Video added:
Maybe one of the GURUS can help?: @JamesW @Arizonarob @ps0303
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