Sta rite maxi therm 400 NG pool heater -service heater light on.


Sep 20, 2019
Sacramento, Ca.
Last night I was heating the spa notice it was taking a long time and would not get above 90degrees.
This morning I was checking this sight for info. I headed to check heater out to see if there were any noticeable issues or codes.
I fired up spa as usual and waited for heater to do something. water temp got up to 70degrees and shut off service heater light came on then a r14 code. I researched coded and went thru and clean filter which I just did a few weeks ago. There were not dirty. I checked for any obstructions where I could and found nothing. I am getting approx. 15lbs of pressure on my tank. I preceded to continue starting and restarting heater with the same issue except I did not get any codes. It would heat to 70 and turn off with "service heater light" for a couple of minutes and then restart.
I took cover off to see if there were any other code places as read in other threads and there are none. (under display or in grey box.) No nests ether.
The heater is less than 2 yrs old.
I also notice the exhaust air was humid to the touch similar to a clothes dryer and the display would would become unreadable from moister.
Any ideas would could be causing issue?
Thx Tony


Gold Supporter
TFP Guide
Jul 21, 2013
Northern NJ
Pool Size
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Thread Status
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