Question about Pentair Mastertemp Heater

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Have a Pentair Mastertemp heater that will fire up and go on for a minute or two but then the temperature display will rapidly increase up to over 100 degrees and then the heater shuts down and displays an E05 code. Any suggestions?

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Posted on Jan 02, 2017

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SOURCE: I have a Pentair Mastertemp 250 pool heater with

This is an ignition flame falure code. Could be you don't have gas getting to the pilot, no spark to ignite the pilot or your ignition is not reading the flame. Sorry to say but it's probally time to get the pool guy out to look at it. Good luck.

Posted on Apr 15, 2010

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SOURCE: getting a E05 code on my Mastertemp pentair

I have same problem. Mechanic not sure what to do. May need a new board.

Posted on Jul 31, 2010

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SOURCE: Pentair mastertemp 200 will work for a while and

If you are firing, and then going off and getting an E05, your igniter is to blame. It may be glowing but it's getting weak. The diagnostic goes further but that is usually the fix. with inactivity, the igniter is always to blame. You really need to fire it off weekly to make it reliable.

Posted on Feb 25, 2011

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Yes, Pentair does make a MasterTemp model heater.

Is that what you needed?

If not, I can keep on guessing...

  • Yes, MasterTemp can be used on a pool, a spa or both.
    • It has a Dual Temperature control, for two separate bodies of water.
  • These heaters come in both types of Fuel consumers: Natural Gas & Liquid Propane Gas
  • You do need to supply electricity to them
    • the supply can be either 120 volts or 240 volts
      • a simple change of a supplied plug
  • If installed indoors you need to vent through the wall or roof
    • Adequate ventilation is required for proper combustion of "Free Air"
  • If installed outdoors, no extra labor required, ready to go
  • Plumbing is simple, just plumb provided unions onto PVC pipe of your system, match up the alignment to the heater & tighten the unions, done.
So sorry, don't mean to be facitious...

But we could use more information to assist you. Your question was sooooo generic.


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1 Answer

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