Heater issues

kristylove36

Member
Apr 10, 2021
5
El Paso, TX
Chlorine
Liquid Chlorine
Hello, I recently moved into a home with an older pool and I'm trying to figure out the heater. It's a minimax 250 tsi nt. When I turn on the heater I get green leds for power, pressure sw and thermostat. Heating light only turns green for a few seconds, there's a huge flame that scares the Crud outta me then goes away as well (I have the doors open to watch) it tries to stay lit 3 times then gives error code E05 and the red service led. I checked the lights behind the control board and the PV led 13 is off. I have already replaced the thermistor, both hi limit switches, the igniter and flame sensor. Any advice other than a brand new heater??TIA
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,587
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
It sounds like you have gas/air mixture issues and combustion issues. IF you are not familiar with how to work with gas systems you should call in a heater professional. You may have sooted burners or lack of air flow. E05 may be a stack flow sensor and an overheat.

If you want, post pics of the insides of your heater and let us take a look.

@swamprat69
 

kristylove36

Member
Apr 10, 2021
5
El Paso, TX
Chlorine
Liquid Chlorine
Hi! Anyone know if something should be plugged into the air pressure switch? Trying to fix my Minimax 250 tsi nt heater and need to make sure I'm not missing anything. TIAPXL_20210410_174523587.jpg
 

kristylove36

Member
Apr 10, 2021
5
El Paso, TX
Chlorine
Liquid Chlorine
It sounds like you have gas/air mixture issues and combustion issues. IF you are not familiar with how to work with gas systems you should call in a heater professional. You may have sooted burners or lack of air flow. E05 may be a stack flow sensor and an overheat.

If you want, post pics of the insides of your heater and let us take a look.

@swamprat69
Thank you, I'm going to take it apart today and see what the burners look like. I will get some pics. Thank you very much!
 

JamesW

TFP Expert
Mar 2, 2011
23,829
Is the blower coming on?

It looks like someone recently disconnected the air pressure switch.

If you look closely, you can see two clean lines on the terminal. That's where the connector was touching the terminal. Someone recently removed the connector because the rest of the metal has a patina that is different from the two clean lines.

They probably bypassed the air pressure switch, which is very dangerous.

Shut off power to the heater and get it professionally serviced.

Is the switch bypassed?

Who recently worked on the heater?
 
Last edited:

swamprat69

Well-known member
Mar 30, 2019
407
Las Vegas, NV
From the corrosion around the burner inlets it looks as if you have had at least a partial flame rollout condition ( sooted/blocked heat exchanger, weak/open blower capacitor, failing blower bearings etc.). The blower air pressure switch ( a MAJOR safety device has been wired out of the safety circuit, a big no-no). I cannot see all of the wiring, but hopefully the thermal fuse (prevents heater from operating if flame rollout is present) has not also been wired out of the safety circuit. It seems that the technician and/or homeowner who last worked on the heater disregarded all safe procedures for operating the heater. The heater is "not safe" to operate in this condition. You need to have the heater inspected by a qualified technician (NATE, RSES or HVAC Excellence certified) as not all technicians are equally competent. ARS/Rescue Rooter is a nationwide company that has NATE certified technicians ( although they are not inexpensive and tend to push replacement with new equipment over repairs, they do have a flat basic service fee for diagnosing equipment problems). You are probably looking at a fair amount of repairs/parts replacement/cost at a minimum. Did you get a "home warranty" with the sale of the home? If so, does it cover the pool equipment?