Looking for help with my AC condenser
I'll do my best to stick to the important details!
The fan in my AC condenser quit working late last fall during heat wave. I don't have a lot of knowledge or experience with HVAC equipment but I have a credit card and amazon, so I replaced the fan motor. Still not working, so I replaced the 5mfd fan capacitor. Now working sometimes but other times the fan needs a little nudge to get spinning. Heat wave over, cold temps coming, leave it for spring.
And now spring is here. The condenser unit is quite old. The dual run capacitor is 40/3 mfd and has an SPP6 hard start kit attached to it. One wire on the herm side and one wire on the fan side. No wires attached to the common on the dual run. The herm side tests fine at 40-41mfd and the fan side gives variable weird readings. The 5mfd fan capacitor was added at some point in the past, I'm guessing because the original 3mfd motor was replaced with a 5mfd motor. My new 5mfd capacitor tests good at 5mfd. I had my new motor wired in the "4 wire" configuration (I was basically rewiring the way I found it) with brown and brown/white on the 5mfd capacitor. I had another look at the wiring diagram and noticed the difference for a "3 wire" configuration, so I took the white fan wire off the the dual run capacitor and put it on the 5mfd fan capacitor in place of the brown/white wire, and the fan spins on it's own right away. But, now I notice that the condenser doesn't seem to be coming on, so I turn off the breaker, disconnect the hard start kit, retest the dual run capacitor herm side (it's good), and turn the breaker back on. When I turn on the AC the fan starts but I get a spark and everything stops. I forgot to cap the brown/white wire and it was loose and it made contact on the enclosure.
The way I left things last night turning on the AC I can hear the contactor close but I'm not getting anything from the fan or the condenser. I've reattached the hard start kit as it was on the dual run capacitor. I've capped the brown/white wire (obviously a bit too late).
I can't think of a reason why the condenser is no longer running.
Have I fried my motor? Is there something I can do to fix it/get it running again?
Should I try replacing the old dual run capacitor with a 40/5 mfd that will run both the compressor and fan (presuming neither are fried)?
TIA for helping me troubleshoot this. I'm determined to fix this on my own. Let me know if i'm leaving out important info or if I should post some pictures.
Comments
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what cap does the replacement require?
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By replacement do you mean the new fan motor that I might have killed? It calls for a 5mfd capacitor, which is what I have installed.
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The dual run capacitor is 40/3 mfd and has an SPP6 hard start kit attached to it. One wire on the herm side and one wire on the fan side. No wires attached to the common on the dual run.
This statement tells me that it is wired incorrectly.
I also see that you changed a white wire from the dual cap to the 5uf cap this leaves you with only one wire on the dual cap if I read you correctly. If the dual cap has only one wire connected then the compressor has no cap connected, and therefore will not run.
Any PSC motor must be wired with a run capacitor like this
Your compressor and your fan motor are both PSC motors, so you need one side of the RUN CAP connected to the L1 side of the motor, and the other side of the RUN CAP connected to the Start winding on the motor. The black wire on your fan motor is connected to L2 and is illustrated by the blue wire in the diagram above.
Any motor that has two brown wires for the capacitor has the brown wire with the white stripe is connected to the white wire inside the motor.
The same is true for the compressor motor with addition of the hard start kit as shown below.
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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oh, is this a schematic described only in words like pspice?
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LOL … Look at the edit. Patience is a verture
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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Single pipe 392sqft system with an EG-40 rated for 325sqft and it's silent and balanced at all times.
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Thanks for posting this, I'm finally getting a better understanding of what's going on, but I'm still missing some things and the wiring in the condenser is kinda screwy.
In the diagram you posted above L2 is the black wire and L1 is the red wire coming in from 240VAC.
Can either be used as the common? Right now I have RED BLACK and BLUE wires going to the compressor. RED and BLACK are attached to L1 and L2 respectively on the contactor and the BLUE wire is on the herm of the capacitor. So all I need here is a common to the capacitor.
The fan is where things get weird. On L1 (red) of the contactor is the WHITE wire to the fan and a wire to the 5mfd capacitor. on L2 (black) is the RED wire to the fan. BLACK fan wire is capped. BROWN fan wire is on the other side of 5mfd capacitor. BROWN/WHITE fan wire is capped.
At this moment the fan spins great when the thermo calls for cool.
I'm about to head over to the HVAC supply house to get a new 40/5 mfd dual run capacitor so I can have one cap to run both fan and compressor.
So now my question is what do I need to change? The wiring diagram in the inside of the access panel is quite faded but I can read that RED L1 is the common for the capacitor and the run side of the compressor. BLACK L2 is the common on the compressor and also goes to BLACK on the fan motor, so I'm guessing I've just substituted WHITE for RED and RED for BLACK on the fan motor and if I run a wire from L1 to the common on the new dual cap I'll be all good?
I hope all of this makes sense! I'll add my hand drawn diagram if it'll help.
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The easiest thing to do is to let me see the wiring diagram for your condensing unit. Can you take a photograph and post it here? The Red or the Black can be the common. And you can also put the red on the L2 and the black on the L1 and it will work just fine when you are dealing with single phase 220 to 240 VAC.
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
0 -
Without the cap the fan motor might have been running but it wasn't running at full speed to there wasn't enough airflow through the condenser so if it is an orifice system it is going to change the balance point of the system.
Take the cover off the terminal block on the compressor, it is held on with a little spring clip. What wires are connected to what letters on those terminals? There will be letters next to the terminals.
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regardless of color, I'm using T1 as the common for the fan capacitor. I'm using the WHITE fan wire on T1 and the RED fan wire on T2. So I will remove the 5mfd fan cap all together and use the wire from it for common on the new dual cap. I think everything will run at that point.
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With separate caps and a single cap wire from the fan motor you have to run T1 to both caps or jumper between the 2. Most caps have terminals that accept multiple quick connect terminals.
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I've just returned from capacitors 'R us and I have a brand new shiny dual cap. So I will use the line from T1 that's on the fan cap as the new common on the dual.
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get the made in mexico ones, the cheap ones tend to have very short lives.
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you have an after market motor. That diagram can’t be used!
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Winner Winner Chicken Dinner! The hot side is hot and the cold side is cold! All is right in the world.
Thanks for the help in getting me to see how it's suppose to be!
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So is the shiny new dual capacitor rating 40 + 5 uf or is it the 40 + 3 uf like the original?
I hope it is the 40 + 5 because you need 5 uf for the fan motor and 40 f0r the compressor motor.
Here is my enhancement of your wiring diagram.
The SPP6 is located where it says Start CAP w/relay. That is an aftermarket version of the Hard Start Kit that the manufacturer might offer on their condensing units.
Common Wire (sometimes white on the new motor) labeled BK for Black from the fan motor gets connected to the T2 terminal on the contactor.
Common or C wire on the compressor (labeled BK for Black) also goes to T2 on the contactor
there are three Red wires on the T1 terminal of the contactor. They go to the R terminal on the Compressor and the Red wire on the Fan motor. The final red wire goes to the C terminal on the dual CAP.
That should make the rest of the wires pretty self explanatory.
If by some reason you do not have a new 40+5 dual CAP and your purchased a 40+3 dual CAP, then you want to wire the good 5uf and not connect to the F on the Dual CAP.
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
0 -
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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Your diagrams are fantastic, thank you! I did indeed get a 40+5 and it's working great.
Funny thing about that start cap (spp6), and I swear this, one of the wires was on the herm side and the other wire was on the fan side, and this configuration was somehow getting the compressor started. Made no sense then and makes no sense still, but that thing is on its way to the great condenser in the sky so I'm not worried.
Thanks again!!
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without c connected on the combo capacitor the current was flowing though both capacitor sections and the start windings of both motors. The windings weren't getting the right currents but it was enough of an out of phase current to make the motors turn but not with their rated power.
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open the door Hal, open the door Hal,
known to beat dead horses1 -
and how do you know this?
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I can follow the path on the schematic. It is similar to having an open neutral in a 120/240 v circuit.
the impedance of the 2 motors might be involved as well.
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Actually the internal wiring of that 40+3 uf CAP makes that a 2.79 uf CAP when you connect to Herm and Fan. You add the reciprocal of both CAPs together when they are wired in series. like this:
So you were using a 2.79 uf CAP with a hard start kit to power the compressor
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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but the side of the line that powers the start windings isn't connected so it is through the impedance of the other motor. you need to draw the start windings in there too then use the impedance version of ohm's law at 60 hz and know the impedance of the windings with the stator spinning in them under some weird condition.
unless the hard start device was connected back to the contactor rather than the otherwise floating center of the combo run cap.
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The fan motor may not be in the equation if this is the wiring diagram @mattmia2
See how the impedance of the fan can not be part of the compressor motor circuit if wired this way? The Dual CAP with 2.79 MFD along with the Start CAP and relay will get the compressor started but the run CAP will grossly undersized when connected this way. Good thing the Compressor has overload protection, or the compressor windings would have burned up and let all the factory installed smoke get released into the freon.
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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I don’t know if that’s how that dual capacitor works?
I’ve gotta do a little research0 -
pecmsg, when using a Cap in parallel you add all the MFD together to get the total so 40 + 3 wired parallel = 43 MFD.
That is why the Turbo 200 is such a good part to have on your truck. It fits almost anything you need and it has a 3 year warranty.
When wired in series the equation looks like this:
That is how I came up with the 2.79 for the 40+3 dual CAP wired in series. When wired like smore1945 indicated in his original post, then the diagram for the CAP looks like this
because the COM terminal connects both the 3 and the 40 in series. This is not the intended use for that CAP, but when you make the mistake and wire it this way, you get what you get.
smore1945 got lucky and was able to save the system by getting it cack the way it is supposed to be.
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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A turbo is not a duel cap!0 -
A dual cap is just 2 caps in the same can with one end of each cap connected to a common terminal so it is 2 caps in series.
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Ed's correct.
Single pipe 392sqft system with an EG-40 rated for 325sqft and it's silent and balanced at all times.
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Actually I have used a turbo as permanent replacement for a Duel CAP many times. To be technical, it is actually a Septuplet CAP ( Duel = 2 Septuplet = 7). So If you need to replace a 40 + 5 Duel then you use the yellow jumpers to connect the 25 + 10 + 5 CAPs to total 40. Then connect the S terminal from the compressor to one of the outer CAP terminals to place the three CAPs that total 40 and the center to the C on the compressor to make them the HERM side of the CAP. The remaining 5 MFD is then used for the FAN by connecting the fan to the COM and the 5 MFD (without jumper)
I'm surprised that @pecmsg has questioned me on this topic. You should know by now that I know my wires? And if I make that rare mistake, I find it and correct it ASAP.
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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It can be.
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I'm just glad there were no fireworks and the OP is still here to write in. How was there nothing on Common on a dual cap?
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I reservemy right to question!
let me do a little research if I’m wrong I’ll admit it
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I'm just surprised your questioning it honestly.
Single pipe 392sqft system with an EG-40 rated for 325sqft and it's silent and balanced at all times.
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Was someone less qualified there before him? OR
Did he make that mistake when installing the replacement fan motor?
He started out with a statement that the unit failed at the end of the previous season and that he installed the replacement fan at the end of the previous season. Once the season ended, the priorities changed and what mistakes were made last season were not part of the new information provided this season.
My guess… He made the wiring mistake last year because he has little HVAC knowledge (self admitted) but has a credit card and amazon.com
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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It was hard to find the instructions for the turbo cap, but once found it is clear that it is just several caps in one can with one end of all of them connected to a common terminal so you just put them in parallel to get the desired capacity.
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@pecmsg said "I reserve my right to question!" and "let me do a little research"
How long do you thing we will wait for this research project? I hope it is not government funded, It may take years.
Edward Young Retired
After you make that expensive repair and you still have the same problem, What will you check next?
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trump cut the funding
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i'm curious what the overload terminal is connected to on the turbo cap. or is it connected to nothing and just a splice point
0
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