# Condenser fan was running backwards until I ...



## justplumducky (Aug 7, 2009)

Nordyne A/C Condenser unit, Model No. ACS030BCRBA (an older unit in mobile home park - Nordyne distributor couldn't bring up the model number in his database - I had to call Nordyne. 
*Data Plate Specs:* 
Comp. Amps: 13.63 
Condenser Fan Amps: 1.25
Dual Run Cap specs from Nordyne (phone call): 35/5, 440v

*What I found:*

Condenser fan running backwards (pulling in air from top and out coil sides). Cabinet not hot (thx Yuri for the warning) and compressor terminals not shorted to bare copper (cleaned up good) suction line.
Compressor pulling 11 Amps.
Compressor ohms check: .9 ohms, 3.1 ohms, 3.9 ohms
Dual run cap was 31/3.4 uf. 
Data plate on Fan motor: 1/12 hp, 1050 RPM / 0.5 Amps.
Ohms check Fan Motor: 90 ohms, 55 ohms, 144.6 ohms

This system was run for at least a few days with fan motor running backwards, but could have been run a lot longer than that - have no way of knowing how long it could have been run backwards. Rust on the fan motor shaft at set-screw (bolt rather) has been there a long time. It's a rippled layer of rust on the shaft.

I installed new dual run cap and fan motor still went backwards while pulling air in at top and out sides. The wiring connections I found (with old cap installed) were correct according to a Nordyne generic wiring diagram for a single phase, 3-wire fan motor with dual run cap and compressor. 

I reversed the two fan motor wires at dual run cap (after installing the new cap) and fan blade reversed direction (starting running CW, looking down at it from above) while pulling air in sides and out the top, but I'm fairly confident it's not enough air out the top (fan motor seems to me to be running too slow) and the air comes out only near perimeter of the fan guard, at a slight outward angle (from vertical), but not as bad an angle I've seen before, as if it were running backwards). 

Since the data plate on the cabinet for this unit specs 1.25 amps for the fan motor, and the data plate spec on the fan motor itself is 0.5 A (it's pulling .68 amps), this is the wrong motor I assume. 

I forgot to check voltages on the secondary side of contactor, but I assume if they were off, I wouldn't have gotten the Amps readings I did (compared to the OEM specs). All wires and connections were good. Checked 'em all - cleaned some.


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## yuri (Nov 29, 2008)

sounds like the motor is dying and the windings are shorting. too much to go thru here but google psc motor and try to understand the theory of how the motor works and why and what the capacitor does. also electric motor theory. the winding(s) is in reality a very long piece of continuos wire if unwound. when the insulation on the wire breaks down from age and overheating then 2 pieces of it touch each other and shorten the effective length of it. then longer the wire or more windings the more horsepower and torque a motor has. also explains why it is drawing less power. if it dead shorts then it blows a fuse.


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## justplumducky (Aug 7, 2009)

Thx Yuri - was hoping someone would speak to the difference in the data plate spec (on cabinet) of 1.25 A for Fan Motor vs. the spec of 0.5A on the motor's data plate. Just made this newbie think this was the wrong motor because of that 0.5 A spec on the motor's data plate. Not an issue? Are you saying it could be a smaller motor with more torque (lower Amp draw) because of the motor's internal construction, which would result in the same or similar RPM's that are required? Something like that? I just saw the lower HP rating than I've seen before - 1/12 hp (in my limited experience however) and then saw the lower amp rating on the motor and thought it was a smaller (not physical size) than supposed to be.


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## yuri (Nov 29, 2008)

I have no idea w/o seeing it but at that age who knows who put what kind of motor in, some hacker? Just get a new motor whatever Nordyne recommends and use that.


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## justplumducky (Aug 7, 2009)

Ok, thx for your help Yuri. I'll call Nordyne in the morning and see what he says about this 1/12 hp, 0.5 A, 1050 RPM motor that's currently installed, and get his recommendation for replacement motor - post back tomorrow morning.


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## HVAC1000 (Dec 12, 2012)

justplumducky said:


> Ok, thx for your help Yuri. I'll call Nordyne in the morning and see what he says about this 1/12 hp, 0.5 A, 1050 RPM motor that's currently installed, and get his recommendation for replacement motor - post back tomorrow morning.


There were a few manufacturers a while ago that did design units to blow into the condenser and out through the coils (they are the worst to clean). Can't say if Nordyne was one of them or not but I know some of them are still around so maybe ask Nordyne if is supposed to blow that way or not also. Just a thought


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## justplumducky (Aug 7, 2009)

HVAC1000 said:


> There were a few manufacturers a while ago that did design units to blow into the condenser and out through the coils (they are the worst to clean). Can't say if Nordyne was one of them or not but I know some of them are still around so maybe ask Nordyne if is supposed to blow that way or not also. Just a thought


Sure will, thx for your reply.


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## taxmantoo (Jun 11, 2013)

The fan blades usually have curvature, cupped in the direction of intended air travel.


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## justplumducky (Aug 7, 2009)

Thx for your input taxman~. 

HVAC1000, I didn't get a chance to ask Nordyne about the direction because I didn't realize they were going to email the fan motor specs - thought I would get a call like last time. However, I see why they emailed it - lots of info. And obviously, I didn't get a chance to ask Nordyne about the existing 1/12 hp/0.5A/1050 RPM motor that's installed now. 

This is, essentially, how it appeared in my email: 

*PART EXTENDED DESCRIPTION INQUIRY* 

PART: 620863 MOTOR,FAN 1/8 H.P. N.L.A. 

*ADD'L DESCRIPTION:*

1100 RPM, 208V-230V, 60 CYCLE,

CW ROTATION FACING LEAD END.

TOTALLY ENCLOSED 1.25 AMP

1/2"DIA. X 2.69 LONG SHAFT W/2 FLAT 1.75 LONG 

3 LEADS 40" +-1" LONG 18 GA.

.06 WALL. 125 DEG C (CLASS B)

NEOPRENE INSULATION W/.250 STRAIGHT Q.C.

TERMINALS (AMP #42400-2 OR EQUIV.)



UE HE3E163N (SAMPLE #S-6753D)

GE #5KCP39CGM688S

A.O.SMITH/WESTINGHOUSE #322P884

EMERSON #KA55HXGTZ-1984

*PART EXTENDED DESCRIPTION INQUIRY* 

PART: 621720 MTR,FAN,PSC,K,1/8,6P,1S,CWLE


*ADD'L DESCRIPTION:*

SEE VENDOR PRINT W/SAME NUMBER

MANUFACTURERS:

BROAD OCEAN: Y7S623B55

EMERSON: K55HXJTC-9302

GE: 5KCP39CGT447S

GEN DESC: PERMANENT SPLIT CAPACITOR,

6 POLE, THERMALLY

PROTECTED, OUTDOOR FAN MOTOR

 ELEC RATING: 208/230 VOLTS, 60Hz

1 PHASE

CAPACITOR: 5MFD/370 VOLTS

FULL LOAD AMPS: 1.2 MAX

HP:1/8 RPM:1100 SPEEDS:SINGLE

ROTATION:CLOCKWISE FACING LEAD END

.


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