Question about Pentair Minimax NT Heater

1 Answer

I shut off the gas to the unit and the power.i

I shut off the gas to the unit and the power for 1 week. i changed the copper heat exchanger. when i tried to fire the unit the fan comes on but the heater doesn't fire. the service light comes on. a service guy said i need the following, flame sensor replaced, thermal fuse replaced, and no voltage to gas valve. the unit was fine prior to replacing the heat exchanger. does this seem correct all these would go out

Posted by on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Expert
  • 83 Answers

No, that does not seem correct. If all you did was replace the heat exchanger, then tried to start it up, how could everything go wrong. Unless there was another issue with the heater. Not too many people change out the exchanger, unless corrosion has caused a leak there What you CAN try to do is reset the heater. To do this, turn off your heater first-at the toggle switch inside the right hand side door, then turn off the circuit breaker to the heater, wait about 5 to 10 minutes, then reverse the order. Circuit breaker then heater, if you have the digital display, you will see flashing codes, this is the computer resetting, then you should see the normal display. Try starting the heater again. If it still will not fire, let me know if you receive an error code. Also, check to see if the temp the heater is reading is close to that of the actual water temp.

Posted on Jul 01, 2009

1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

2 Answers

Where is the heat exchange in a rheem pool heater located ?

The PVC plumbing is hooked into the front header, the front header is attached to the heat exchanger. The heat exchanger looks like copper finned tubes with a steel plate on each end. You need to disassemble heater working from top down to get to the exchanger. A skilled tech can replace an exchanger in under one hour service call.

Aug 19, 2014 | Rheem 266K to 399K BTU Swimming Pool...


Renting and Paying the Gas Bill

This past week I changed out an old hot air furnace in a rental unit that made me question why the tenant did not go to the owner and offer to pay more rent in exchange for getting the furnace changed out sooner. If you are a renter that is paying the gas bill, then you need to think about this.
The hot air furnace was at least 60 years old. It had been coal fired furnace that was converted to gas many decades ago. The pilot light of this beast was more of a torch than a pilot light. When the thermostat called for heat the flame roared for 15 minutes before the exterior blower unit that was added when the furnace was converted to gas, started up to move air through the furnace and into the house.

As I was starting up the new unit, which took up less than 1/3 of the space of the old beast, the renter came and sat down on the basement steps looking on in amazement. How would that little thing make enough heat for the house? A few minutes later those questions were put to rest very quickly.

After starting the new furnace and burning off the oil that always smokes up the house a bit on a new startup the new little unit had the house warm as toast and was shutting down. Wow, that took less time than the old beast took to just warm up!

The renter related to me how that the old furnace cost over one hundred dollars a month just to run the pilot over the summer months. The wintertime heating bills were many times higher than that. The difference between the bills of the old unit and the bills that will be coming now will be unbelievable. A savings of 40-50% is not at all out of the question.

Now, if you are renting and are paying the bill to feed an old monster of a heating system, I suggest that you make a proposal to your landlord. Offer to pay a bit more rent in exchange for a new heating system. Not only will you decrease your gas bills enough to pay some extra rent and still come out ahead, but you will have the peace of mind that you have a safer heating system under the roof that you also live under.

on Dec 07, 2009 | Heating & Cooling

1 Answer

My jandy xl 250 pool heater runs great for 5-6 minutes with a blue flame then it turns orange and runs hot ive replaced all 5 burners wire brushed and power-washed the heat exchanger. I tore it all apart...

bad mixture is correct. heater is under firing, lack of oxygen, hence the immense amount of soot or carbon build up underneath heat exchanger. Is heater inside a shed? if so u need 2 vent openings to provide combustion and ventilation air. vent blockage can also cause sooting and over heat conditions. your repair guy lacks alot of knowledge. burners and heat exchangers can be cleaned. i can give you a list of reasons of possible problems that im sure were never mentioned or checked

Aug 11, 2013 | Pool & Spa

1 Answer

Heil epm36f19a1 runs but no heat

Fan relay is stuck among other things. The thermostat turns on the combustion air fan and puts power to the spark unit. If the burner comes on after the temperature in the heat exchanger rises the indoor fan will then come on. After the thermostat comes to temperature the power to the gas valve which shuts off the burner. Then after the heat exchanger cools a bit the indoor fan will stop. That's the sequence of events. look at the switches that control the fans. There is a wiring diagram somewhere on one of the panels that access the unit for service.

Mar 06, 2013 | Electronics - Others

1 Answer

Having problems with metal staining. i was told that i should clean the heat exchanger. can i just take off the front header & flush the tubes with some d-lime. Thanks

There is a very specific method for cleaning heat exchanger tubing and using any acidic cleaner could potentially cause damage to the tubing, especially if it is erroded. As to metal staining in your tub... cleaning the heat exchanger is NOT the answer! If the staining is copper, then cleaning the heat exchanger is NOT going to correct the problem!. Your heat exchanger is likely copper and if it is the source of the copper staining, then the problem is NOT the heater, the problem is your water chemistry. In most pool service calls I have done, involving staining from copper or iron, the most common problem was low pH. If your test is showing a pH of lower than 7.2, then add pH increaser (baking soda) based on a base demand test. If after adding the needed amount of pH increaser, the pH remains below 7.2, then perform a pool stabilizer (cyanuric acid) test. If the results show higher than 80ppm, drain at least 50% of the volume and refill and retest again. A high stabilizer level in excess of 100ppm will result in a low pH and cause metals like copper to dissolve and stain the pool. Get the level down to around 30-40ppm if possible. Stabilizer is added to chlorine tablets to help hold chlorine in the water longer. You can unstabilized chlorine, but chlorine consumption is higher as a result. If the staining is copper, you should dismantle and inspect your heater for erosion and possible early stage leaks. Replacing the heat exchanger can be very costly. Proper preventive maintenance and chemistry balance will keep the staining issue under control. There are some products available on the market to assist with balance, staining treatment and overall chemistry control. I suggest looking at products by EasyCare, called Pooltec, Scaletec and Beautec. These may be beneficial for your situation.

Aug 04, 2011 | Hayward H-series Electronic Gas Pool...

1 Answer

Water turned green was blue this am heater off for 1 week browncolor in water and filter is heater damaged?

First thing you need to do is check the pH of the water. If the pH got too low, below 7.0, this could be caused by copper from the heat exchanger in the heater. If the pH is ok, this could be nothing more than an algae bloom because the pool ran out of chlorine. Not quite enough information to answer your question.

Jul 24, 2011 | Teledyne Laars Laars Lite 2 Pool Heater...

2 Answers

Purex triton powermax 400- gas ignites for a moment and then shuts off - basically cycles on and off for the spa. any idea to the problem?

This is usually either the Thermal Overload Cutoff (an inline fuse to prevent overheating) which costs $13.50 through, or it is that you are not getting enough water pressure through the heater. There are sensors that will shut down the heater if there is not enough water flow. Is your filter clean so enough pressure/flow is happening?


1 Answer

Furnace runs about 1 minute, then total shutdown

What type of gas supply line do you have? Is it black pipe or copper? If it is copper, there can be a film like substance that builds up on the inside of the copper. The debris will the get caught in a pre screen where the supply enters the valve thus cutting the supply of gas to the unit. Also, the thermocouple may be bad. You didn't say that you replaced it. Try replacing it as well. Also, you could have a limit switch turning the system off and thus cutting the gas off completely but it is highly unusual for the pilot to be cut off as well unless the pilot is being blown out when the gas is shut off. Also, turn the unit to fan only without calling for heat. Using a flame of some sort, put it into each baffle of the heat exchanger. If your flame is being blown around in one of the baffles, then you have a hole in the heat exchanger and what is happening is that the roll out switch is cutting the unit off and the air still moving through the heat exchanger is blowing the pilot out. I have seen this actually happen. If your furnace is in excess of 15 years old, it does need to be checked for possible holes. If it is in excess of 25 years old, it is a huge possibility that the unit has already developed a hole. If you feel hair coming out of one of the baffles, then shut the unit down immediately and have it replaced!

Apr 05, 2009 | Heating & Cooling

Not finding what you are looking for?
Pentair Minimax NT Heater Logo

348 people viewed this question

Ask a Question

Usually answered in minutes!

Top Pentair Pool & Spa Experts

Pj Kiley
Pj Kiley

Level 1 Expert

21 Answers

Jay Finke
Jay Finke

Level 3 Expert

1338 Answers

Bill Jordan

Level 2 Expert

372 Answers

Are you a Pentair Pool and Spa Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides