Pentair Minimax NT Problems?

Electric heaters, gas heaters, heat pumps,
solar heaters, geothermal heating, solar pool
covers and wood-burning pool heating equipment.

Pentair Minimax NT Problems?

Postby ndllana » Mon 03 Mar, 2008 20:22

I ahve a Pentair minimax NT . The heater starts and heats for about 30 minutes or so then just stops. It will kick back on several times, then fi nally stops and shows and e05 messaage. Anyone have a fix to this.

Thsi is the second time this has happened since I bought it back in 2003. The first time Pentair came out and replaced the ignition module and DDTC controls.


Postby Guest » Thu 22 May, 2008 21:34

I am a pool heater technician and I would recomend throwing that peice of crap away and buying either a Jandy or Raypack heater. Nothing but problems with the mini max.

heater issues

Postby 96fatboy » Mon 08 Dec, 2008 10:40

Everyone says throw that away instead of trying to fix the problem. Nt heaters are easy to fix and diagnose. The most common problem is the gas supply to the heater. If the pressue is not right the heater will give intermittent problems. E05 is a flame rectification issue...could be flame sensor or gas pressure. If the unit is a couple years old the first thing to do is clean the orfices out with a small wire or orfice brush.
I'm new here
I'm new here
Posts: 2
Joined: Tue 21 Apr, 2009 12:24
My Pool: We over see the operation of community pools and spas in CA WA & OR. We are the Tech service for upgrade, repair, trouble shooting of systems in large mobile home parks, resorts and some RV parks.
Location: United States

Pentair Minimax NT Problems?

Postby BearHotTubs » Tue 21 Apr, 2009 13:41

Heater venting problems. The original heater lasted 23 yrs, now we have to make serious repairs to the Mini Max 400 that is 4 yrs. Old, and the third new heater in 10+ yrs. This is the state of the art unit that is supposed to solve venting problems by using fan forced venting. The fan motor burnt out and was replaced by factory at about 2 yrs. The unit fan and module burnt up again after 1.7 yrs. And factory offers no help adding the information that this unit is obsolete. So much for their problem solving state of the art venting solution. I don't want to use another mini max, that's for sure.
We have moved the unit outside and will replace parts with hopes of no overheating or venting problems. If replacement is needed I'll take the advice of "Pool User".
Swimming Pool Superstar
Swimming Pool Superstar
Posts: 302
Joined: Thu 26 Feb, 2009 11:11

Postby Me... » Tue 21 Apr, 2009 15:02

Pool User wrote:I am a pool heater technician and I would recomend throwing that peice of crap away and buying either a Jandy or Raypack heater. Nothing but problems with the mini max.

Seconded on the Raypak. Since Jacuzzi and Tropic heaters went AWOL the only good heater on the market is Raypak. Not that they haven't had issues but noone has done anything to their heaters to actually make them noticeably more efficient, easier to repair/troubleshoot, install etc. What they have done is computerize the hell out of them, shrink them too small and add useless unrequired features that make them a lot like the Hot Tubs these days ...... throw aways.

Pentair Minimax NT Problems?

Postby jcombs » Wed 25 Nov, 2009 07:57

I have the Mini Max NT Nat Gas 400 and I have replaced the blower motor assembly twice in 5 years because it rusted. It has a rubber ture on the side that goes to a vacum switch, I an not getting sucton from the blower assembly to the tube can anyone tell me if the suction out of the barb is strong enough to feel?
pool baby

Pentair Minimax NT Problems?

Postby pool baby » Thu 26 Nov, 2009 14:19

I have a Minimax Nt gas heater. The technician put a new heating element on it because it stopped heating. Stated it was fixed . Now when I turn it on the heat light comes on for about 10 seconds and the blower then it shuts it's self off. Any suggestions?
I'm new here
I'm new here
Posts: 1
Joined: Sat 12 Dec, 2009 14:24
My Pool: Free form 15' x 30', 15,000 gallon inground pool with spa and waterfall. Two 2HP pumps, filter, and heater (Pentair Minimax 400 NT TSI). Installed 2004.
Location: Los Angeles

Pentair Minimax NT Problems?

Postby Artman » Sat 12 Dec, 2009 14:42

I own a Pentair Minimax 400 NT TSI. It was installed in 2004. For the first couple of years it worked fine. For the past two or three years I've noticed that the heater has a problem staying on when there's wet weather, like during and after a good rain. Then I have to go through the ignition sequence up to 10-15 times before it really stays on. I also noticed that a lot of steam blows out of the top vent port while it's trying to get going. When there's no more steam blowing out the heater finally stays on.

When the weather gets dry again everything is fine. What's up with that?

Pentair Minimax NT Problems?

Postby fireman » Tue 23 Feb, 2010 20:32

Got a pentair minimax nt tsi customer and the heater is plagued with problems. Finally got everything working, but I have had to install a hot surface ignitor 3 times now. I called Pentair and they said it was cracking from condensation water hitting the ignitor from the cold. I should wait until it warms up, then replace it AGAIN then the home owner can use the pool. WHY IN THE HELL would they want to use the heater when its warm outside?
The ignitor keeps cracking. DOES ANYONE have ANY ideas about what is going on with the hot surface ignitor?
By the way, No error codes are given. Just broken Ignitors.
El Paso fiream

Pentair Minimax NT Problems?

Postby El Paso fiream » Wed 05 May, 2010 14:01

Can anyone help with a Mini Max problem that Iam having.
The pre-heater seems to work, but when the heater seems like it is going into the second stage it sounds as if a baffle of some sort is closing. Any ideas? Iam about to give up on the whole Pentair product line.

Pentair Minimax NT Problems?

Postby papoolservice » Fri 09 Jul, 2010 10:35

I've been working on heaters for 20 years. the nt tsi - as well as most electronic heaters - but this pentair being the worst - IS JUNK. Every one I've installed I was back replacing flame sensors and blowers within a year. As far as the HSI, just trying getting one shipped! I had three broken in shipping before I got one that was in one piece. Installing or removing them is a surgical procedure as they are more fragile than glass. If you have condensation building up on one you may have an insulation problem.

i am fighting with one AS WE SPEAK and have replaced the valve, the blower, vac sensor, flame sensor, fenwal control, and tested both incoming and differential pressures with no problems. However, E04's and E05's continue to pop up, and this thing is an hour away from me.

My advice - if you REALLY want something that's easy to diagnose, stick with MV, and if you do commercial work, Raypak DOES make an ASME header in MV. Raypak is a bit more expensive but worth it - it's all they do - and they have taken strides to make them easier to work on, based on service tech complaints such as mine. Apparently hayward is getting into ASME this year but they're all electronic.

Putting electronic controls in units that are burning in the hundreds of degrees is just bad practice...the sensors and controllers should be located somewhere outside of the heater, then maybe you'd have something. The blowers burn up fast - especially if the heater is used alot. I have a 250kbtu on a condo pool, 19000 gallons, no cover, and they want the temp at 88 constantly. The heater burns constantly and they don't want to hear that there are cheap parts in their heater. they think I'm putting garbage into the heater - it's all OEM parts, they're junk. Let the customer fight with it for a few years and then talk them into a good price on a millivolt. Install a relay and put a power vent inline in the stack. You'll accomplish the same thing and be able to troubleshoot it in 5 minutes or less every call you get.

recycle the heat exchanger and use that money to lower the customers price for the new heater. you'll save two headaches.

Pentair Minimax NT Problems?

Postby Artman1 » Sun 18 Jul, 2010 22:06

pool baby wrote:I have a Minimax Nt gas heater. The technician put a new heating element on it because it stopped heating. Stated it was fixed . Now when I turn it on the heat light comes on for about 10 seconds and the blower then it shuts it's self off. Any suggestions?

I had a very similar problem with mine. I replaced the flame sensor (about $17) and all's okay now.

Pentair Minimax NT Problems?

Postby mdrdpchc » Tue 20 Jul, 2010 20:39

how can fix e04---fan failure.

Pentair Minimax NT Problems?

Postby hmiller-2010 » Tue 27 Jul, 2010 06:37

:shock: Call and get tech support.

Pentair Minimax NT Problems?

Postby poolandspaguy59 » Mon 12 Sep, 2011 17:07

I have had nothing but bad with this heater. very expensive to fix. problem after problem. if you have nothing better to do and alot of money. but one. i only bought one but paid for 2 in as little as 4 years and i dont charge myself labor. no joke they suck...

Return to “Solar & Pool Heaters”

Who is online at the Pool Help Forum

Users browsing this forum: No registered users and 1 guest