Blower will not come on!

mt400

Member
Sep 22, 2022
5
Idalou/Texas
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I have an error code on the Fenway ignition system that is stating air flow fault - 1 flash. The blower is not coming on. I have tried everything I know how to check and cannot get the blower to come on. Help please.
 

JamesW

TFP Expert
Mar 2, 2011
31,503

AFS Error[edit]​

AFS is the air flow switch that senses if the blower is on and there is sufficient air flow to the burner. Sequence is blower motor should turn on, AFS senses air flow through a white tube down by the burner can, and switch closes to start the ignition sequence.

You can gently blow into the white tube and you should hear the click of the air flow switch turning on. Check the white tube for cracks or breaks. The white tube is not available as a separate part and comes with the Pentair MasterTemp & Sta-Rite Max-E-Therm Air Flow Switch assembly P/N 42001-0061S.

If you hear the air flow switch closing then check the continuity of the air flow switch relay using a multimeter. Connect the multimeter to the two contacts on the air flow switch after removing the heater wires. You should see it electrically open when no air is blown into the switch and closed when air pressure is through the tube.

Testing the Air Blower[edit]​

Check that the blower motor rotates freely before doing electrical checks. Sometimes the blower has began running by simply cleaning debris from the fan area or removing the cover to the blower motor and using a screwdriver to manually turn it.

Note: No guarantees on anything. Only do what you know that you can do safely. Do at your own risk.

The blower has 3 sets of windings.[19] 2 main run windings and an auxiliary start winding. Red and blue go to one set of windings. Black and yellow go to the other set.

  • For 120 volts, the windings are in parallel.
  • For 240 volts, the windings are in series.
The auxiliary start winding is in parallel with the black --> yellow winding.

Remove the capacitor and test for resistance from red to blue and black to yellow. The values should be the same.

  • Label the capacitor wires C1 and C2.
  • Test from C1 to C2, C1 to black, C1 to yellow and C1 to white.
  • Test from C2 to black, C2 to yellow and C2 to white.
Test from each wire to the green ground wire to see if any wires are shorted to ground.

Check the power going to the blower[20]:

  • When the heater tries to start, you should be seeing 240 volts from red to black on the wires going to the blower.
  • You can disconnect the blower plug and test the power at the red and black wires.
  • Have the meter connected because the power might shut off after a few seconds.
  • The red should be powered any time the heater is powered.
  • So, you should get 120 volts on that leg before the heater tries to start.
  • The black wire doesn't get power until the blower is supposed to be on. When the heater tries to start, power is applied to black and you should get 240 from red to black.
To test the motor directly wire as follows:

  • For 240 volts, Black to hot leg, Red to the other hot leg, blue and yellow connected together.
  • For 120 volts, red and yellow to one line, black to the other line and blue and white connected together.
  • The white wire is connected to the black wire, so cap it off when applying power to the black wire so that it doesn't make contact with anything.
If the power test shows that the motor is good, the problem is likely to be with the ignition control module or the main board.

Note: the above is believed to be correct. It's presented as is. If you want to test like this, you do it at your own risk.

Do the resistance test first as that should tell you something.

Test the capacitance of the capacitor to make sure that it's correct.

One power leg is always connected to the blower motor and the black wire from F2 is the switched leg.

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