Pentair Minimax NT Problems?

[Indi]

My Minimax NT isn't working - When I checked it out, I smelled gas so I turned off the pilot, then turned it back on, only to smell gas again (now it's off). Also, I noticed water seepage on the sheet metal on the bottom of the heater and on the ground below and around the heater. Could these be related?

[Icanfixanything]

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?

Next time instead of replacing the entire blower, you can easily replace the blower wheel as it is common that it rusts and falls apart. The part # is Fasco 1-6143. Cost $27 and fixed it in about 20 minutes.

[Leonking]

My heater is showing An eo4 problem. The heater was wrking fine all summer and mysteriously stoped heating. Had a tech come out to look at it and within 10 min said it was a bad fan. That he could not diagnose it any future without that fixed first. He then said that the price for the fan is 550 to 650 dollars. I had to send him away for now. Is he rt? Any help would be appreciated.

[Not a heater repair guy]

I'll give everyone having weird intermittent behavior with their Pentair Minmax heater a hint up front, before the long story below. REPLACE THE RUN CAPACITOR ON THE FAN MOTOR! It is a $10 to $20 part that can be replaced in 15 minutes. Just waste $20 and do it first and see if it fixes all your problems.

Turn off breakers, confirm no power to unit, remove 6 screws on top that hold the fan cover down, pull the cover up and off, and remove and replace the oval run capacitor. You need a 5MFD, 370 V or greater oval capacitor, available on the internet or most HVAC supply stores.

E04, EO5, fan eventually not running, ignitor module flashing once, twice, control panel eventual not powering up were all caused by the capacitor slowly degrading and taking out the AC transformer and low voltage power to the ignition module and DDTC controller board.

The next post gets the long story.....

[Not a heater repair guy]

Long version of the previous post, read the post before this for the short version if you are getting E04, E05, reseting panel, all with fan apparently running fine. A $10 part might fix all your problems!

I'm an engineer, I like fixing things. I have a pentair minimax, about 7 years old. Worked fine except after about 3 years, it would throw and E04 right after a big rain storm. By the time things dried out and I got out to fix it, it would clear.

About a month ago, heavy rain, EO4, more persistant than before. Sometimes run, but mostly E04. Plenty of time to fix it this time. Fan is running; must be the fan switch. I replace it; E04 with fan running. Check the hose, clear the hole into the fan; E04 with fan running. Look at the motor housing, what a crappy job they did sealing it up with goop, maybe it is leaking. Go to the autoparts store to get some high temp RTV (it is hot down there), seal it up real good; EO4 with motor running!

I decide to simulate the proper operation of the fan switch with a wire (leave terminals open until I hear the fan, then short them with a wire). Heater starts! WTF? Repeat this a few times, once out of ten times the fan fail light comes up on the ignitor, one other time it flashes twice (no heat after ignition) but mostly starts. WTF?

After the 10th time, the entire panel goes blank, won't come up. Check the AC transformer that powers up the panel. No output. Transformer blown? WTF? Was the transformer feeding flakey power the the modules and make them act weird?

Order a transformer on the internet for $40 including shipping (local price $60 to $160, and I had to wait 3 days and then go back and pick it up when it came in). Easy install, except one mounting hole was off and had to open it up with a drill. Power up and voila, panel lights up. Turn it on and whish, heater starts up.
I go off and crack open my beer, come back, and the unit is shut off! WTF?

Turn it on, and fan doesn't start. WTF? Power is going to the fan, but not running. Touch the motor housing and almost burn myself. Touch the run cap, crap really hot. Remove it, do the capacitor test with multimeter (look it up on the internet, short the cap first for safety) and it tests bad. Order a cap on the internet beacuse it is midweek, and HVAC places only like to open between 10:00 and 3:00 on weekdays.

Get the cap, install it in 15 minutes, power up. Whoosh fires right up!. Turn off, power up 3 for 3. Let it run, cycles, works GREAT!

The sequence of most likely events was that the run cap slowly degraded, and was throwing all kinds of electrical spikes back into the input power. The messed up input power feed through the step down transformer, corrupting the power to the ignitor and DDTC controller, causing wierd behavior at first, then eventually blowing the input transformer itself. The cap then degraded to the point that the motor wouldn't even run. Thnak god it finally completely died and pointed me to the root cause of all my problems!

Let everyone know if this fixes your problem, or if it was just my bad luck. I have a feeling a lot of bad motors, ignitors, and other problems are just due to a $10 cap wearing out....

[AnotherOne]

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]

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]

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]

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]

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]

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]

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]

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
damato@cox.net

[/user]

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]

5E

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?