The supplied told me that the white wire on the new motor was the same circuit as my OE black wire. According to my schematics both motor black wires are for high speed. My old motor had 5 wires: brown to capacitor, white to neutral/line, black to hi on the control board (which also has a black wire to the other side of the capacitor), blue-med, red-low & of course grn/yel to case ground. the new motor is labeled: white-common/line, brown-cap, brown 5mfd370vac(was told by supplier to cap & not use), black-hi, blue-med, red-low & grn/yel-case ground. I installed the new motor & wired white-neutral, black-hi(jumper still in place from hi to cap., brown to other side of cap, blue-med, red-low. Now, here's the thing, the lo terminal has a yellow lead going to the fan & limit switches which is where the black common/line is also connected. now the blower runs the instant you turn up the t-stat when the burner lights. But when the temp in the room gets up & the t-stat cuts off the burner, the fans stops right away instead of running a little longer to cool off the burner & the motor hums. Also, if you switch the circulator switch to manual for only blower operation (no heat) you get the same hum & I get 115v on the low speed red wire. Please help if you can.
Some one missed the wiring diagram. I believe its like this:
L1 = Line 1 = (Hot all are same thing)
Black Hi
Blue Med
Red LO
Now usually the black is for AC and connects to a normally Open (NO) contact on the blower relay.
The heater speed (either red or blue) go the the normally Closed (NC) on the blower relay and on one side of this wire or contact on the relay it goes to the heating blower thermostat on the furnace.
The remaining wire (blue or red) you tape off.
L1 also feeds the Run Capacitor on 1 side and the Brown wire feeds the opposite side
The white wire is Neutral and goes to the neutral on the main line.
If this helps you please rate me accordingly and good luck.
Well Maybe I wasn't clear about what I was pointing out.
Can you list me the colors and terminals designations on your motor. This way if you have something different than what I believe you have maybe I can correct it in my mind and tell you what I believe.
SO how many wires going to your capacitor? and what / where are they coming from? And what colors are they?
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This fix can't be right. I have the OE wiring diagram as well as the
new motor diagram, if needed.
Here's the skinny: New motor has 6 leads: Brown to capacitor,
Brown/white (I was told to tape off/not used), Black-hi speed, Blue-med speed, Red-low speed, White-common/line.
My O.E. wiring diagram: White from motor to neutral line in only, black to hi terminal on board in blower control box (no blower relay, this is an oil fired furnace-heat only). This hi terminal also has a black wire going to capacitor, brown from motor to other side of capacitor, blue-med terminal on board, red-lo terminal on board which also has a yellow wire going to the blower limit switch. This limit switch has the black common 115v line in circuit. The auto/man circulator switch is a simple rocker type, 2 pole switch. In auto, the circuit is open, in manual the circuit closes. Both wires are yellow, one to the black common line in going to the limit switch & the other goes to the lo terminal on the board which also has the yellow wire going to the fan limit switch. The circulator switch basically bypasses or overrides the fan limit switch. Please help further if you can, I'm having trouble comprehending how the old motor worked in all phases based on this wiring diagram & wiring setup, but I checked it before disassembly & I know it did. The only problem was worn shaft bushings causing noise on start-up & after running awhile.
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