Ok thanks. I’m ordering a new AFS switch. It must be staying open not closing. What happens when spa heater is turned on, see both temps ok with pool water below the set temp, the blower motor starts and runs about 45 secs with heating light on and then I get AFS error flag. The motor continues to run until heater is turned off. I can feel air coming out of chamber stack vent and feel air being sucked in from blower. It’s been tough getting to the bottom of this.
Mastertemp 400 AFS error no power to blower
- Thread starter MLCarlson
- Start date
- Jul 21, 2013
- 65,727
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Your hand is not a good measure to determine if you have sufficient airflow to close the air flow sensor.
We have seen heaters where the blower runs but the burner can is clogged with rats nest blocking the airflow, or the blower motor is not spinning at proper speed and giving the needed airflow.
I have not gone back and read through your thread to see what you already replaced or examined.
Pentair MasterTemp Heaters - Further Reading
www.troublefreepool.com
Remove one of the bottom manifold bolts to see if water comes out, which would indicates a leaking heat exchanger.
www.inyopools.com
Sta-Rite Max-E-Therm & Pentair Mastertemp Heater Manifold - 77707-0015 - INYOPools.com
77707-0015 - MANIFOLD 333 (77707-0015)
www.inyopools.com
Thanks again, I don’t know what happened to cause all my issues except it was working until we had a hurricane and the sand filter tank which is 2 feet away from heater busted and sand went everywhere. Since those two events I got a AFS error. Called spa pool tech to house, he determined blower motor is bad. I replaced blower motor (old one’s fan was frozen and it had corrosion but no animals). Next, the new motor would not start unless F1 and F2 jumped. Still AFS error too. I could not adjust temps either so called Pentair, they said membrane and control board bad. I replaced both. After, still no power to blower motor. The Pentair troubleshooting flow chart said replaced ICM so I replaced FENWAL. Also, I have checked all wiring voltage from new control board to ICM and the fuse, all good. Now now have blower motor turning on but still get AFS error.Your hand is not a good measure to determine if you have sufficient airflow to close the air flow sensor.
We have seen heaters where the blower runs but the burner can is clogged with rats nest blocking the airflow, or the blower motor is not spinning at proper speed and giving the needed airflow.
I have not gone back and read through your thread to see what you already replaced or examined.
Pentair MasterTemp Heaters - Further Reading
Ok, thanks, I’ll do it. I did look inside the chamber by sliding a camera into the stack flute opening. It looked dry no water. I was thinking of taking the new blower motor off again to see if I can look down the funnel for obstruction?
Ok, thanks, I’ll do it. I did look inside the chamber by sliding a camera into the stack flute opening. It looked dry no water. I was thinking of taking the new blower motor off again to see if I can look down the funnel for obstruction?
James, you still there? I took the bottom screw off manifold and no water. I also ordered a new AFS and put it on. I’m stIll getting a AFS error with new switch. When I turn heater on, blower starts (after new ICM) but in few seconds I get AFS and no ignition so no burner. Any ideas?
Yes, started out with heater service light and AFS error. The blower motor would not turn on. I called pool tech and he said blower motor was bad. I installed new blower motor, it new would not start and same AFS error. I could not adjust temps on membrane pad. I installed new circuit board and membrane pad, service heater light gone but no blower and still AFS. I checked voltages and installed new ICM. Now, blower starts but still AFS error after few seconds.
Seems like you have replaced all parts that can cause the issue, so I don't know what the issue could be.
How old is this heater?
What is your total cost for parts so far?
What is your total for number of hours spent on this?
This is exactly why I usually recommend replacing a heater instead of spending over $1,000.00 on parts and tens of hour in labor to get something that might or might not work.
If you cannot get it to work, you basically have lost all time and money spent.
If you were a service person who bought the parts and did the labor, you would have to eat that cost because the customer isn't going to pay $1,500.00 in parts and $2,000.00 in labor (Total $3,500.00) for an old heater that does not even work.
How old is this heater?
What is your total cost for parts so far?
What is your total for number of hours spent on this?
This is exactly why I usually recommend replacing a heater instead of spending over $1,000.00 on parts and tens of hour in labor to get something that might or might not work.
If you cannot get it to work, you basically have lost all time and money spent.
If you were a service person who bought the parts and did the labor, you would have to eat that cost because the customer isn't going to pay $1,500.00 in parts and $2,000.00 in labor (Total $3,500.00) for an old heater that does not even work.
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Looks like 2016 from the label.
That's not that old, but the fact that the blower was frozen points to some sort of excessive corrosion, which might be due to water in the combustion chamber or maybe stray current etc.
It seems like you have replaced all major parts, so I don't know what else to try.
I would probably have just replaced the heater when the blower was found to be seized.
That's not that old, but the fact that the blower was frozen points to some sort of excessive corrosion, which might be due to water in the combustion chamber or maybe stray current etc.
It seems like you have replaced all major parts, so I don't know what else to try.
I would probably have just replaced the heater when the blower was found to be seized.
Ok, it's unusual for the blower to seize at only 7 years old so something went dramatically wrong.
Did mice get inside?
Any chance that water somehow got into the exhaust?
Maybe a sprinkler system or maybe a house downspout?
Did mice get inside?
Any chance that water somehow got into the exhaust?
Maybe a sprinkler system or maybe a house downspout?