Pentair Minimax NT Problems?

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AnotherOne

Pentair Minimax NT Problems?

Postby AnotherOne » Sat 28 Jan, 2012 14:34

I have searched long and hard for an explanation, or at least a confirmation, as to my whacky, totally unpredictable Pentair Minimax HP heat exchanger problem. It seems you may have provided the answer, but just to be sure I don't waste another dime on this beast:

Well, I bought it used. What can I say? It worked, when we first hooked it up, in the summer. Hot days, dry climate, cool nights . . . but yes, after a rain, no go. Just wouldn't start up. I started to cover it during rains, which seemed to help.

Note: There was a crappy install by the "pool guys" - they ran insufficient power to it, which caused the circuit to pop until I finally hired an electrician to put a sub-panel in and wire it correctly. This power snafu could have fried some things? But . . . it worked, except for the rain issue, afterwards, so I didn't worry.

As the weather started cooling, in the fall, it started behaving erratically, and eventually stopped working all together. Now, I get it - it's a "heat exchanger", and is not optimal in cold weather. But here's the rub . . . in November, we experienced a cold snap . . . and it was between 15 and 35 degrees F. for about a week. The damn thing worked fine, just chugging away out there, doing it's job. Then . . . nothing again.

I called an heating/AC guy to come out and have a look. They came more than once . . . and eventually wound up replacing the control board (a hefty cost, and a long wait). It worked for about a week . . . and then, nada. I winterized the spa after that.

Last week, thinking it might be "warm enough" for the heat exchanger, and that that might have been the problem, I gave it a shot. And . . . wallah! It turned on! It heated up the water . . . for a few days. And then back to the erratic behavior again. The latest thing is this, and this is a question for anyone out there that might know about this: For the last several days I just leave the thing on and hope it will "go on". And the funny thing is, it has . . . but it seems to be going on at timed intervals . . . like, it goes on consistently around 6:30 a.m., and will run for 4 or 5 hours . . . then nothing. It's strange, because it's the coldest part of the day . . .

So that's the story . . . if the fan element replacement thingy would work, I'd be a happy camper, I'm just wondering if there's more to it . . .

Thanks in advance for any feedback or advice.

DT


not a repair guy

Pentair Minimax NT Problems?

Postby not a repair guy » Fri 06 Apr, 2012 10:48

You can order the run cap on line for $10 to $20, and change it in 15 minutes (breaker off, top cover off, open the band, slide the two leads off, slide them back on the new part, tighten band, replace top cover, breaker on, done!) . Just give it a try....
Andy Jung

Pentair Minimax NT Problems?

Postby Andy Jung » Tue 17 Jul, 2012 00:06

Minimax NT heater problem?

The NT works fine when the heater's not turned on, but whenever the heater is on, I hear a strange knocking noise from the machine. Does anyone know the reason why this happens?
mps

Pentair Minimax NT Problems?

Postby mps » Sun 29 Jul, 2012 17:35

Sounds like a water flow issue make sure all ball valves are opened .make sure there is not a bypass valve opened let me know if I can help
mps

Pentair Minimax NT Problems?

Postby mps » Sun 29 Jul, 2012 17:40

Sounds like a water flow issue make sure all ball valves are opened .make sure there is not a bypass valve opened let me know if I can help
mps

Pentair Minimax NT Problems?

Postby mps » Sun 29 Jul, 2012 17:46

Sounds like a water flow issue make sure all ball valves are opened .make sure there is not a bypass valve opened let me know if I can help
alanf_45
Pool Newbie
Pool Newbie
Posts: 1
Joined: Thu 16 Aug, 2012 10:31
My Pool: Angular, 15,000 gallon, 2 HP pump motor and motorized valves, Minimax NT heater from early 2000's
Location: United States

Pentair Minimax NT Problems?

Postby alanf_45 » Thu 16 Aug, 2012 10:40

My Minimax NT problem is that I must cycle through the start-up 2-4 times before I get ignition. I turn it on, wait a few minutes, turn it off, wait, turn it on, wait, turn it off, and THEN on the 3rd try, I get ignition and it heats the spa just fine.
Two separate repairmen listened to this story and both told me the repair would be too costly, compared with the cost of a new heater. Both told me to replace the heater and not waste my time and money on repair attempts. I am adding solar water heating panels for the pool, and plan to replace the heater in a few months.

Anyone have a short term solution I can do myself? Pushing a few buttons on an X-10 keypad is NOT all that difficult.
Alan
Guest

Pentair Minimax NT Problems?

Postby Guest » Wed 02 Jan, 2013 19:24

I have a Minimax NT heater that is 7 years old (purchased in mid-2005). Just recently, when the pool/spa water is in the mid-50 degree range, the heat does not come on. The blower/fan can run for an hour or more and the heat does not come on. The unit control panel says that the water flow is fine, but the led shows "LO."

However, when I switch the settings from "remote" to "on" and run the unit, the heater comes on. All of my plumes are running when I do that.

Is there a set water temperature below which the heater will not kick on remotely (i.e. from my compool panel in the house as opposed to manually starting the heater at the unit itself.)

Any thoughts?

Thanks

Dale
[email protected]
/user

Pentair Minimax NT Problems?

Postby /user » Sun 10 Feb, 2013 14:00

Hi there,

Long story short, my fan rusted, tech comes in, tells me to replace fan (entire Gasket for about $350) and control board (another $350). I found the Fasco part, just the piece that rusted, thanks to someone here, $30. Get the board. Spent 2 weekends on it (gasket disassemble was rough, but I think it was just my luck, and how bad the fan went, the replacement process is simple), get everything in place. nothing. bypass the board and voila. works. The board is brand new, but when I try to manually or remotely start it. It just doesn't do anything, just shows OFF.

On bypass, I get Power, Thermostat and Heating lights on on the outside of the panel, and all four (hitemp, PV, Tfuse and fan) on the inside, and the thing works.

Without the bypass, just power.

Any suggestions?
markwimbush

Pentair Minimax NT Problems?

Postby markwimbush » Thu 21 Feb, 2013 19:33

5E
Andy Jung wrote:Minimax NT heater problem?

The NT works fine when the heater's not turned on, but whenever the heater is on, I hear a strange knocking noise from the machine. Does anyone know the reason why this happens?



Is it plumbed with the water flowing in the correct direction?

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