Question about Pentair Minimax NT Heater

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I have a pentair minimax nt heater. The screen reads HI and the heater won.t ignite. I suspect a high temp probe. Is this something a lay person can replace? If yes where would I find the instructions.

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Hi means the unit believes the water is 114 degrees or higher. The problem, assuming the water is really not that warm, is the thermistor in the header. You need to replace it with a new one as its function is to read water temp and feed that info back to the control board. It is a part most people can replace on their own.

Your part number should be: 471566

If this answer does not fix your problem, please comment with additional details prior to rating the answer. You may also contact me thru our website at Positive feedback is appreciated once your problem is solved!


Posted on Mar 11, 2011

Testimonial: "John224, Your evaluation was right on target. I purchased the thermister and installed it in 5 minutes. Thanks for the info."

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