Heat Pump Fan Motor Install Question

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Please correct me if I'm wrong, but I am thinking it is only a 230v system because of the capacitor.
CY: Most central AC and heat pumps, use 230 volt compressor, and 230 volt fans.
There appears to be only 1 pole powering the fan motor.
CY: One pole is switched.
Does one refer to both wires power a 110v appliance as hot? Admittedly, they are both carrying current.
CY: In 110 appliances, there is typically a black hot, and a white neutral.
In your terms, the latter hot wire is connect to common, or somewhat equivalently, back at the main panel, ground.
CY: From the fan wiring I've done, black and yellow are both hot.
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Stormin Mormon wrote:

But only when the fan is actually running, right (see what I mean, there IS a difference). Kind of like whether you put a disconnect in front of an appliance or after it.
TY VM SM! I've "seen you around" the Usenet
Bill
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Both black and yellow are hots. One of course is switched. So, one is hot only when the contactor is pulled. (switched hot, y'know.) But, if you follow the wires to the other side of the contactor, they are both hot, all the time.
In the case of 110 volt appliance, one is hot, other is neutral. Switched on or off.
YW, glad to have met you around the usenet.
Christopher A. Young Learn more about Jesus www.lds.org .
Stormin Mormon wrote:

But only when the fan is actually running, right (see what I mean, there IS a difference). Kind of like whether you put a disconnect in front of an appliance or after it.
TY VM SM! I've "seen you around" the Usenet
Bill
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Stormin Mormon wrote:

SM: I think I'm getting it at another level. There nothing to keep what's on Common from coming back, if you will, and zapping you in the butt!!! : ) I'd say that qualifies it as "hot". Is that about right?
Bill

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I believe SM is incorrect. NEC requires both legs (conductors) to be disconnected by the contactor for a 240VAC load.
The motor will be a single phase 240VAC 60HZ motor (well, technically split phase, but there is a single electrical phase driving it).
Each of the black and yellow will measure 120v to ground if you test them with a multimeter, and they should test 240v to each other when the load side of the contactor is energized (the line side of the contactor will measure hot unless the compressor disconnect is activated or the breaker is disenaged).
scott
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Hmm. I've worked on a lot of illegal devices, then. Most residential AC outdoor units have a single leg that's switched.
Christopher A. Young Learn more about Jesus www.lds.org .
I believe SM is incorrect. NEC requires both legs (conductors) to be disconnected by the contactor for a 240VAC load.
The motor will be a single phase 240VAC 60HZ motor (well, technically split phase, but there is a single electrical phase driving it).
Each of the black and yellow will measure 120v to ground if you test them with a multimeter, and they should test 240v to each other when the load side of the contactor is energized (the line side of the contactor will measure hot unless the compressor disconnect is activated or the breaker is disenaged).
scott
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writes:

One leg remains energized with miliamp current so that winding acts as a crank case heater in the compressors. this is especially important in heat pumps.
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230 volt systems typically don't have a common wire. They have two hots, and a ground.
Christopher A. Young Learn more about Jesus www.lds.org .
Stormin Mormon wrote:

SM: I think I'm getting it at another level. There nothing to keep what's on Common from coming back, if you will, and zapping you in the butt!!! : ) I'd say that qualifies it as "hot". Is that about right?
Bill
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Stormin Mormon wrote:

Thank you for helping me to accept that. Alot of evidence was building up on that side, and I've been fighting it tooth and nail. The wiring diagram, and the rest of the pieces, makes more sense in that light!
Dern lady at the electrical supply emphasized I should attach the yellow wire to Common!!!
Thank you again!
Bill

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If you follow the wires back to the circuit breaker panel, the black and yellow should go to a two pole circuit breaker, providing hot and hot.
Christopher A. Young Learn more about Jesus www.lds.org .
Stormin Mormon wrote:

Thank you for helping me to accept that. Alot of evidence was building up on that side, and I've been fighting it tooth and nail. The wiring diagram, and the rest of the pieces, makes more sense in that light!
Dern lady at the electrical supply emphasized I should attach the yellow wire to Common!!!
Thank you again!
Bill
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On 5/11/2012 7:37 PM, Bill wrote:

Oh silly me, that's what I get for posting while tired. The darn motor is a 240vac motor so technically both wires are hot. On the contactor you may see a black and a white or yellow in your case. The contactor will have 1/4" Faston tabs for the flat push on connectors like the tabs on the capacitors. The black wire to black and yellow to the light colored wire which will have a jumper going to one side of the run capacitors for both the fan motor and compressor. Often there is a dual capacitor with three terminals with markings like "C" for common, "F or Fan" for the brown wire and "Herm" for the compressor. The brown/white wire from the fan motor can be taped up if the dual capacitor is used and the "C" terminal will have a jumper back to the switched side of the contactor's light colored wire. Oh, the contactor is inside the control compartment on the side of the condensing unit where you will see the flexible power conduit attached to the bottom of it. If you got a new capacitor with your new fan motor hook the brown and brown/white to the terminals on the new capacitor and leave the "F" terminal on the dual capacitor in the control box unconnected. Anyway, there should be a safety switch or disconnect next to the condensing unit to turn off the power to the unit before you try to work on it. If not, find the circuit breaker and kill the power to the condensing unit. Be safe. ^_^
TDD
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The Daring Dufas wrote:

From what you wrote, I believe that I need to connect the motors yellow wire back to the switched side of the contactor, no?
Thank you for the lesson!
Bill
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On 5/12/2012 11:45 PM, Bill wrote:

Same with the black wire, the only other wires attached to the incoming power side of the contactor besides the hot wires would be an optional crankcase heater. There are a few different crankcase heaters but there would be a pair of small wires that stayed energized when the compressor isn't running going to the CC heater which can be a stainless steel band that wraps around the lower part of the compressor housing or a ceramic cartridge around an inch in diameter stuck into a well in the base of the compressor. ^_^
http://www.tutco.com/conduction_heaters/crankcase_heaters /
http://www.myhvacparts.com/store/crankcase-heater.php
https://en.wikipedia.org/wiki/Crankcase_heater
TDD
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The Daring Dufas wrote:

As I had my condensing unit disconnected for a few days, I reconnected it to evaporate any of the refrigerant that may possibly have combined with the crankcase oil. Even if I replace the fan, I'll be sure 24 hours have passed before I test the system. That's the "standard" waiting period, isn't it?
Bill
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On 5/14/2012 3:57 AM, Bill wrote:

You could always heat the crankcase with a propane torch. ^_^
TDD
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What? And avoid the background check?
Christopher A. Young Learn more about Jesus www.lds.org .
On 5/14/2012 3:57 AM, Bill wrote:

You could always heat the crankcase with a propane torch. ^_^
TDD
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face=Verdana>...</FONT></DIV> <DIV><FONT face=Verdana>&gt; On 5/14/2012 3:57 AM, Bill = wrote:<BR>&gt;&gt; The Daring Dufas wrote:<BR>&gt;&gt;&gt; On 5/12/2012 11:45 PM, Bill wrote:<BR>&gt;&gt;&gt;&gt; The Daring Dufas = wrote:<BR>&gt;&gt;&gt;&gt;&gt; On 5/11/2012 7:37 PM, Bill wrote:<BR>&gt;&gt;&gt;&gt;&gt;&gt; The Daring Dufas wrote:<BR>&gt;&gt;&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt;&gt;&gt;&gt; There a probably four long wires not including those to the rotation<BR>&gt;&gt;&gt;&gt;&gt;&gt;&gt; selector plug and those wires for a single speed motor are usually<BR>&gt;&gt;&gt;&gt;&gt;&gt;&gt; one black, one white, one brown and one brown with a white stripe.<BR>&gt;&gt;&gt;&gt;&gt;&gt;&gt; The white and brown with white stripe are usually connected together<BR>&gt;&gt;&gt;&gt;&gt;&gt;&gt; inside the motor as the white is the neutral power connection which<BR>&gt;&gt;&gt;&gt;&gt;&gt;&gt; should also be connected to one side of the fan motor run capacitor.<BR>&gt;&gt;&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt;&gt;&gt; Mr. Dufas, You were closer in guessing what I was going to recieve<BR>&gt;&gt;&gt;&gt;&gt;&gt; than<BR>&gt;&gt;&gt;&gt;&gt;&gt; I was. Indeed, there are 4 wires : one black, one yellow, one brown<BR>&gt;&gt;&gt;&gt;&gt;&gt; and<BR>&gt;&gt;&gt;&gt;&gt;&gt; one brown with a white stripe. Evidently they made this change for<BR>&gt;&gt;&gt;&gt;&gt;&gt; safety reasons. The brown wire as well as the the brown and white wire<BR>&gt;&gt;&gt;&gt;&gt;&gt; go to the capacitor. Black goes to hot as before and Yellow goes to<BR>&gt;&gt;&gt;&gt;&gt;&gt; Common. Although I haven't opened the unit's electrical box today,<BR>&gt;&gt;&gt;&gt;&gt;&gt; it is<BR>&gt;&gt;&gt;&gt;&gt;&gt; this last connection which mainly concerns me. Can you suggest<BR>&gt;&gt;&gt;&gt;&gt;&gt; where to<BR>&gt;&gt;&gt;&gt;&gt;&gt; make this connection? I am not too lazy to try to decide for myself,<BR>&gt;&gt;&gt;&gt;&gt;&gt; but<BR>&gt;&gt;&gt;&gt;&gt;&gt; your reply may give me more confidence. I expect to possibly find a<BR>&gt;&gt;&gt;&gt;&gt;&gt; wire<BR>&gt;&gt;&gt;&gt;&gt;&gt; nut connected to Common from the power supply in the unit's electrical<BR>&gt;&gt;&gt;&gt;&gt;&gt; panel, and I would make the connection there. Is that right?<BR>&gt;&gt;&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt;&gt;&gt; Bill<BR>&gt;&gt;&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt;&gt; Oh silly me, that's what I get for posting while tired. The darn motor<BR>&gt;&gt;&gt;&gt;&gt; is a 240vac motor so technically both wires are hot. On the contactor<BR>&gt;&gt;&gt;&gt;&gt; you may see a black and a white or yellow in your case. The contactor<BR>&gt;&gt;&gt;&gt;&gt; will have 1/4" Faston tabs for the flat push on connectors like the<BR>&gt;&gt;&gt;&gt;&gt; tabs<BR>&gt;&gt;&gt;&gt;&gt; on the capacitors. The black wire to black and yellow to the light<BR>&gt;&gt;&gt;&gt;&gt; colored wire which will have a jumper going to one side of the run<BR>&gt;&gt;&gt;&gt;&gt; capacitors for both the fan motor and compressor. Often there is a dual<BR>&gt;&gt;&gt;&gt;&gt; capacitor with three terminals with markings like "C" for common, "F or<BR>&gt;&gt;&gt;&gt;&gt; Fan" for the brown wire and "Herm" for the compressor. The brown/white<BR>&gt;&gt;&gt;&gt;&gt; wire from the fan motor can be taped up if the dual capacitor is used<BR>&gt;&gt;&gt;&gt;&gt; and the "C" terminal will have a jumper back to the switched side of<BR>&gt;&gt;&gt;&gt;&gt; the<BR>&gt;&gt;&gt;&gt;&gt; contactor's light colored wire. Oh, the contactor is inside the control<BR>&gt;&gt;&gt;&gt;&gt; compartment on the side of the condensing unit where you will see the<BR>&gt;&gt;&gt;&gt;&gt; flexible power conduit attached to the bottom of it. If you got a new<BR>&gt;&gt;&gt;&gt;&gt; capacitor with your new fan motor hook the brown and brown/white<BR>&gt;&gt;&gt;&gt;&gt; to the terminals on the new capacitor and leave the "F" terminal on the<BR>&gt;&gt;&gt;&gt;&gt; dual capacitor in the control box unconnected. Anyway, there should<BR>&gt;&gt;&gt;&gt;&gt; be a<BR>&gt;&gt;&gt;&gt;&gt; safety switch or disconnect next to the condensing unit to turn off the<BR>&gt;&gt;&gt;&gt;&gt; power to the unit before you try to work on it. If not, find the<BR>&gt;&gt;&gt;&gt;&gt; circuit<BR>&gt;&gt;&gt;&gt;&gt; breaker and kill the power to the condensing unit. Be safe. ^_^<BR>&gt;&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt;&gt; TDD<BR>&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt; From what you wrote, I believe that I need to connect the motors yellow<BR>&gt;&gt;&gt;&gt; wire back to the switched side of the contactor, no?<BR>&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt; Thank you for the lesson!<BR>&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;&gt; Bill<BR>&gt;&gt;&gt;&gt;<BR>&gt;&gt;&gt;<BR>&gt;&gt;&gt; Same with the black wire, the only other wires attached to the incoming<BR>&gt;&gt;&gt; power side of the contactor besides the hot wires would be an optional<BR>&gt;&gt;&gt; crankcase heater. There are a few different crankcase heaters but there<BR>&gt;&gt;&gt; would be a pair of small wires that stayed energized when the compressor<BR>&gt;&gt;&gt; isn't running going to the CC heater which can be a stainless steel band<BR>&gt;&gt;&gt; that wraps around the lower part of the compressor housing or a ceramic<BR>&gt;&gt;&gt; cartridge around an inch in diameter stuck into a well in the base of<BR>&gt;&gt;&gt; the compressor. ^_^<BR>&gt;&gt;<BR>&gt;&gt;&gt;<BR>&gt;&gt;&gt; TDD<BR>&gt;&gt;<BR>&gt;&gt;<BR>&gt;&gt; As I had my condensing unit disconnected for a few days, I reconnected<BR>&gt;&gt; it to evaporate any of the refrigerant that may possibly have combined<BR>&gt;&gt; with the crankcase oil. Even if I replace the fan, I'll be sure 24 hours<BR>&gt;&gt; have passed before I test the system. That's the "standard" waiting<BR>&gt;&gt; period, isn't it?</FONT></DIV> <DIV><FONT face=Verdana></FONT>&nbsp;</DIV> <DIV><FONT face=Verdana><EM><U>It depend on type gas was in system and type of oil???</U></EM></FONT></DIV> <DIV><FONT face=Verdana><EM><U>You as technician must decide that at time you examine the equipment.</U></EM></FONT></DIV> <DIV><FONT face=Verdana><EM><BR></EM>&gt;&gt;<BR>&gt;&gt; Bill<BR>&gt;&gt;<BR>&gt; <BR>&gt; You could always heat the crankcase with a propane torch. ^_^<BR>&gt; <BR>&gt; TDD</FONT></DIV></BODY></HTML> ------=
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Grumpy wrote:

The length of the line is an important fact took no?
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I think there's a waiting period, and a background check. Oh, you were talking about crankcase heaters?
Christopher A. Young Learn more about Jesus www.lds.org .
As I had my condensing unit disconnected for a few days, I reconnected it to evaporate any of the refrigerant that may possibly have combined with the crankcase oil. Even if I replace the fan, I'll be sure 24 hours have passed before I test the system. That's the "standard" waiting period, isn't it?
Bill
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That shouldn't be a problem or an issue unless its either a heat pump and its winter, or you turned the condenser upside down.
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