I have a Pentair Minimax NT with error code E04 and unit will turn on blower will start then you here the ignition for the igniter. It fires either for a few seconds or a minute or two then shuts down and the error message comes on.
Pentair Minimax NT with error code E04
- Thread starter otabrab
- Start date
A couple of things can cause this. Possible bad air flow switch, tube on the air flow switch is chewed up or not connected, water in the can causing the system to not correctly ignite, or a bad blower motor. Most of the times when I see this the blower motor is shot and I need to replace it.
Thanks Paul! Ive looked into the heater and the blower is running and seems to be blowing air quite well. The tube is obstruction free and in pretty good shape. ( this unit is inside a pool house utility room) could anything else be trouble shot? Or should I just buy the new blower motor?
Have you popped the top off the heater and inspected the air tube as well as the hood that covers the heater exchanger? I would also pull the blower motor out and inspect the squirrel cage and make sure it is full intact. It might feel like it's blowing strong but if that cage is messed up in any way it will not allow the right about of air flow.
I incorrectly mentioned water in the can. I was thinking of a different heater for some reason. Yours wouldn't have this issue.
I incorrectly mentioned water in the can. I was thinking of a different heater for some reason. Yours wouldn't have this issue.
Ok, I've checks ohms, I've checked volts, I switched out the air pressure switch, I tested the igniter, I changed the flame sensor, I've check the gas. The fan blows hard as I said. The rubber tube seems to be in good condition and debris free. Unit did fire for a few hours then E04 again. When things cooled down I pulled the vacuum hose off the blower assembly and created negative pressure on it by sucking while the unit cycled. Viola it ignited and ran fine, but as soon as he stopped it shut down E04and the single red flash from the fenwal. So we figured there had to be some type of obstruction in blower housing. I pulled the blower unit off heater and it was perfectly clean inside and all parts seemed to be free spinning with no bearing problems. Now this blower was blowing hard like a shop vac in reverse so I cannot for the life of me figure why it isn't creating the vacuum needed to operate that pressure switch. Is there a way of checking this while blower is off the heater?
Check the little port on the blower housing where the vacuum tube connects. About 20% of my no-heat furnace calls each winter have an obstruction in this port. Be careful sucking on the vacuum switch. It only takes about .5 - 2" of water column to activate one of these. Too much and you can rupture the diaphragm. The only way to accurately test the blower is while it is on the unit and have a manometer (water Column) hooked to it
ok I have done absolutely everything! Except change blower. According to enter Tech Service the pressure switch that actually came in my heater from factory is meant for a much higher elevation. That Aside they said to jump the switch to see if it would start. I did this and the heater started and ran fine for about 10 hours then it shut off before reaching desired temp. No unit will not let me jump the switch nor will it even engage the start up sequence. It just shows me an ERR code. I called pentair again and they said at this point it was either the water temp sensor or the mother board. Well I figure $40 on a water temp sensor was with the cost while trying to trouble shoot. When trying to change the sensor and unplug the wires I noticed that almost all the wires that were on the front side of the wall including the main power lines coming in from the waterproof conduit were all charred and black! Where could this have come from? If it was a flame all the metal and the paper stickers and or plastic would have been burned as well but it was just the wires, almost all of them. If I could post a picture here I could show you all what I am talking about. Thanks in advance for the help.
I am having the same issue with my Minimax NT. Fan comes on igniter fires and flames start for a second then go off. Please keep us posted with any resolution.
ERR is usually the thermistor, water temp sensor. A quick test to determine if this is the issue is you can remove the sensor wires from the board and then lick your finger and hold it on the spot where they were attached to the board. Now turn the heater on. It should fire up like normal if this is the cause of the problem.
Charred black wires tells me that for some reason flames were shooting up in that area. Check and make sure the burner tubes don't have spider webs or something blocking them in side.
Charred black wires tells me that for some reason flames were shooting up in that area. Check and make sure the burner tubes don't have spider webs or something blocking them in side.
ok I rewired everything after getting charred. Changed the water temp sensor etc. everything started back up fine for about 2 hours then E04 again!!!! I jumped the air pressure switch and everything started again just fine. I let it run a while and when I cam back the blower was off but the flames were still burning so I turned off power at the breaker. I waited about an hour and started up again and all worked fine I went inside got busy, forgot to check it and went to the grocery store and when I cam back after about an hour and a half it was all melted again! After speaking to certified Pentair warranty service tech and him telling me it could be a bunch of other things including the heat exchanger even if it wasn't leaking I came to this conclusion. Too much aggravation for me and $1604.00 shipped to my door Via Amazon i Bought a new water heater just for safety sake!
If you have the extra cash and can make it work just buy a new heater!! Supposedly this was a bad design and you really never know what the E04 is coding for and that comes right from the warranty service reps mouth. He is service rep for several of the major names and recommended the Hayward H Series it has a Standard Cupro Nickel Heat exchanger which has excellent corrosion resistance over most other models. $1604.99 delivered to my door From Amazon!!
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If you have the extra cash and can make it work just buy a new heater!! Supposedly this was a bad design and you really never know what the E04 is coding for and that comes right from the warranty service reps mouth. He is service rep for several of the major names and recommended the Hayward H Series it has a Standard Cupro Nickel Heat exchanger which has excellent corrosion resistance over most other models. $1604.99 delivered to my door From Amazon!!
Out of the frying pan and into the fire. Hayward is the least suggested unit on this site as well as several others. As for the cupro nickel, not worth it. It is over sold to too many people with the hopes that it will last longer than regular copper. Not 100% true. I've seen cupro nickle heat exchangers eaten thru in as little at 18 months. Pretty aggressive water but proof it can happen.
Keep an eye out for the ICB board to go bad as well as the display board. These units are prone to this issue.
I don't mean to degrade your purchase, I just don't like to see people spend good money on mediocre products.
Keep an eye out for the ICB board to go bad as well as the display board. These units are prone to this issue.
I don't mean to degrade your purchase, I just don't like to see people spend good money on mediocre products.
gklein: did you ever resolve your Minimax NT fan issue? I am havingthe same problem today.
I am having the same problem. Fan turn on, heat come on, then a minute later it shuts off with the same error codes (on the panel and internally). I changed the flame sensor and the temp probe. I bypassed the air flow switch. Still have the same problem. Any new thoughts or ideas?