pentair mastertemp 400 service system

[prasadkm0204]

so i turned on the spa (to check if temperature sensor is working posted in another thread ). if turned on a for a bit and stopped with service system. i tried again after sometime and it did not turn on but continued showing the service system light on. )

looks like not so pleasant start this season ( sensor, leak and now this ).

 

[ajw22]

Check that the gas valve is open.

Check the diagnostic LEDs on the back of the board or the flashing LED on the FENWAL box.

See Pentair MasterTemp Heaters - Further Reading

 

[JamesW]

Service System means that the Pressure Switch is open.

 

[prasadkm0204]

I haven’t started full on troubleshooting yet. I’ll do this maybe over the next-to-next weekend or as time permits. (tired and happy that 2 of the 3 issues are resolved as of now hopefully).

The gas valve is open and has always been open. The panel is in a not so easy to reach. I opened on the accessible side but there is nothing much on that side.

I’ll read up more on the 2 pointers that you folks have mentioned.

 

[bradgray]

Like James mentioned, Service System is named such to insinuate something in your system is problematic, vs Service Heater which indicates a fault detected in the heater.

Start with your flow. Ensure pump RPM is set high enough and your filter PSI is within 10 of your baseline (new filter reading).