I have a Pentair MasterTemp 400 heater. It's about 15 years old and get's considerable use. I've had to replace the control board about a year ago and over the years, there has been considerable rat damage to the wiring.
Recently the display became intermittent and the heater would fail with different error lights, so I replaced it again. It appeared to be fixed, but now when cold, it starts (releasing considerable steam) and then shuts off after the 20 seconds heat up time indicated on the Fenwal ignition.
There is considerable rust on the tub and my thinking is that the heat exchanges has a leak, so during the initial startup, the heat sensor in the exhaust stack does not get up to temperature fast enough because the energy is going into creating steam. On the second attempt is runs just fine.
I replaced the heat sensor and they both show this behavior, so I don't think that's the issue. I tried testing with an ohm meter and both read open, but show voltage when heated. Is that correct?
At this point my best option may be to just replace the heater since it's near end of life, but if I could get another year or two out of it, that would be great. I can live with restarting it, but it occurred to me that if I could change the 20 seconds to 30 seconds, it would probably solve the issue. Does anyone know if this is possible?
Thanks in advance for any help.
Recently the display became intermittent and the heater would fail with different error lights, so I replaced it again. It appeared to be fixed, but now when cold, it starts (releasing considerable steam) and then shuts off after the 20 seconds heat up time indicated on the Fenwal ignition.
There is considerable rust on the tub and my thinking is that the heat exchanges has a leak, so during the initial startup, the heat sensor in the exhaust stack does not get up to temperature fast enough because the energy is going into creating steam. On the second attempt is runs just fine.
I replaced the heat sensor and they both show this behavior, so I don't think that's the issue. I tried testing with an ohm meter and both read open, but show voltage when heated. Is that correct?
At this point my best option may be to just replace the heater since it's near end of life, but if I could get another year or two out of it, that would be great. I can live with restarting it, but it occurred to me that if I could change the 20 seconds to 30 seconds, it would probably solve the issue. Does anyone know if this is possible?
Thanks in advance for any help.
