Mastertemp 400 with no fan spin up....or backwards spin up. I've read through a few of the other threads on here regarding the same issue: Service heater light and a humming fan motor. If I give the motor a spin in the correct direction, it will spin up and heater fires normall.
I'm pretty handy with schematics/meters and meggers so I ran some checks based off the diagram @JamesW provided. Mine is wired for 240 using the plug so I checked supply ac voltage on the red and black wires to the motor. Measured 239vac
Pulled the back off the motor and removed the capacitor, unplugged the motor plug. Ran some megaohm checks (insulation checks) on shorts. No windings are shorted to ground.
Black to yellow: 11.3 ohms
Red to blue: 11.4 ohms
C1-C2 1.3 ohms
C1- yellow: .1 ohms
C1-white: 11.3 ohms
C1-black: 11.3 ohms
C2 to Yellow: open
C2 to black: open
C2 to white: open
capacitor was hard to measure since I have a FLuke 88, just climbs and climbs. I'm assuming the CAP is a run cap and not a start cap. Usually if a motor has 2 caps then one is start and one is run
Megger checks:
Red-Yellow: open circuit
White-yellow: closed circuit
White-black: closed circuit
CP1-white: closed circuit
CP1-Yellow: closed circuit
Cp2-Yellow: closed circuit
My best guess is I have a bad start winding in this mini motor. Anyone know if you can just get a elect new motor or anyone know if a rewind shop can rewind it? Dropping 4500 for a new heater seems ridiculous when I can change out the motor or have it rewound.
Anyhow, gimme your best guess based off what I did
PS I did notice this strap, looks burned.
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