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Old 02-08-2013, 02:20 AM
denman denman is offline
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Motor running, I had the wires off of the element and checked between the wires and frame.
This is a bit of a puzzle, since the element is not in circuit it cannot conduct the L2 voltage to the right side (BR) of the element.
There is a possibility that you were measuring the L1 voltage on both wires.
It would conduct the right side through the normal heater circuit path. Then depending where your TEMP SWITCH was, it could conduct the same voltage through the CYCLING thermostat's internal heater to the left side BK BK

I did not understand completely on your path on right side.
I just cannot figure out why I don't see 240 when going across the two legs.
Is there anyplace where it wuld tell me the voltages I should see across all contacts when running?

Not that I know of.
Your problem is that using voltage is confusing because you have two 120 volt supplies (L1 and L2) referenced to ground and there is no way of knowing which supply you are measuring unless you have an oscilloscope.
That is why using resistance is a better trouble shooting method for everything except the motor's centrifugal switch.
With the unit unplugged and the timer set to mid scale, timed dry, regular heat. Using the most sensitive meter scale and one lead on L1 and left there.
You should read 0 ohms back through the heater circuit all the way to the right side of the main heater (BR).


Are you saying red from cycling therm to temp switch red to temp switch blue to bu on timer closes to bk to L1 is the path?

Yes.

So L1 is hot all the time and the timer closes to allow voltage flow to BU?
Yes, timer switches 3 and 4 are closed when the heater is supposed to be on.
Then when the motor gets close to operating speed it's centrifugal switches close and L2 is applied to the left hand side of the heating coil.
There is a live test that may help your troubleshooting, hopefully the BK heater and the BK cycling thermostat heater have plugs on both wires so they can be disconnected from each other and the main heating coil.
Then with the motor running you should see 120 volts (main heater's BK wire to ground). This then tell you that the centrifugal switch is closing and that you are getting L2 to the heater.
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