I am replacing an old Honeywell single pole, 24V, 30 Amp contactor with a new Packard contactor. I've looked at numerous videos and can't figure out where the black and yellow wires below the switch circled in green are supposed to connect on the new contactor? Thanks!

 

The first picture is the Old Honeywell contactor. The 2nd and 3rd pictures are the new Packard contactor.

 

In the pic old Honeywell contactor ,

Red are the incoming 240 VAC power wires , blue 24 VAC coil wires , yellow are 240 VAC outgoing power wires .

Green are also 240 VAC power wires , that connect to the stationary pole / bar that just feeds through & is not switched / broken .

The two Packard photos ,

Color code is the same .

The 2 green wires connect to the stationary pole / bar that just feeds through & is not switched / broken .

God bless
Wyr

 

Take a closer look as the feed-through bar was on top.

I think that the green circles (yellow and black wires) are for a crankcase heater. So the black wire should go with the lower red circle on the left and the yellow wire with the lower yellow circle on the right. That way the heater turns off when the compressor turns on.

 

I was just reviewing this thread and saw the same thing as astuff noticed.

The yellow and black wires do appear to be for a crank case heater. A little surprised one is needed in California unless you have cold temps where you are.

 

Astuff/PJMax: For the green circled wires, the black one is connected to the compressor. The yellow one is connected to something that goes back towards the fan.... it does appear to be connected to a crank case heater since the black wire goes to the compressor.
I previously tried to connect as you mentioned, and the fan turned on when I manually pushed in the switch. Compressor didn't seem to turn on but was warm. Wide range of temperatures here. Can get to the 20s in winter, and up to the 100s in the summer. Supposed to be in the 100s tomorrow. Hoping to get this figured out before then!


WyrTwister: I tried your connections, when I manually pushed in the switch, it buzzed a little...nothing turned on then it stopped buzzing.


Also now after replacing the contactor, my thermostat isn't calling to the AC or the blower in the house. It has the battery indicator on, which I've replaced and nothing....suggestions? Thanks for your help!

 

You may be right . I may be seeing it wrong , as to which is the stationary pole and the movable contact .

Can you please post a good / clear pic of the old contactor , now that you have it removed from the condenser & it has the wires removed / out of the way ?

God bless
Wyr

 

OK , after thinking about this a little more , go turn the 240 VAC off , at the condenser . Turn the furnace off and then back on . At the furnace , measure if you have 24 VAC at the red and common wires or terminals . If you do , set the tstat to cool and turn the set point down enough so the tstat will be " calling for " the condenser to run .

Back at the condenser , with the 240 VAC power still off . Do you have 24 VAC on what looks to be brown and orange wires , that I have circled in blue . One on each of the 2 side of the contactor coil ?

If so , is the movable contact pulled in / closed ?

God bless
Wyr

 

Wyrtwister-

Pic 1: Old Honeywell Contactor
Pic 2: Inside of Furnace

Before changing contactor: Thermostat was calling to the outside unit compressor and blower inside was working. The reason why I was changing the contactor was because it was old (12+years) and my compressor wasn't turning on.

Current situation: Have the new contactor connected as Astuff/PJMax mentioned. Thermostat doesn't seem to be getting the 24V (It was before). Thermostat has battery indicator on (with new battery). Can no longer turn on inside blower or call to the compressor.
I looked inside the furnace, and it doesn't appear to look like any I've seen online. It is fairly old...pic 2 shows the inside. I was looking for a fuse or switch to see if I blew it somehow in changing the contactor. Not sure where to test if the 24V are going to the furnace...take a look at the pic 2.

Thanks for your help!

 

I forgot to ask , do you have a volt - ohm meter ? You need one to do much troubleshooting . If you do not have one , you can pick one up from Harbor Freight for around $ 10 that will get you through this .

Your 2nd picture , bottom right there is a cable with some twisted wires and 1 orange wire nut showing . Good chance that is the cable going to the thermostat .

The red should be your 120 VAC " hot " & blue may be the 24 VAC " return " . Try measuring voltage between those 2 wires . Should be 24 VAC with power on , at the furnace .

Above those wires id a larger cable entering the furnace . You can see a little of the white plastic jacket , covering the cable . But most of the jacket has been removed , revealing a black , white and bare earth ground .

This should be power entering the furnace . Do you have electric resistance heat ? If so , the power is probably 240 VAC . Otherwise , 120 VAC . In either case , I recommend you be very careful when poking your hands around inside the furnace . Turn the power off & check it with the meter , unless you have to gave the power on to check voltages .

The power wires extend across the photo and continue to the left . I do not see a 24 VAC transformer in the photo . It is probably some where off to the left . You need to check & see if it is outputting 24 VAC . If not , check to see if it is receiving power , either 120 or 240 VAC .

While you are doing this checking , I would also turn the 240 VAC power off , to the outside condenser unit .

Report back with your findings .

Your picture of the old contactor is a lot better . Thank you . Once you verify you are getting 24 VAC to the new contactor , you can get back to it .

God bless
Wyr

 

After a few cups of coffee & further inspection , the transformer appears to be in the middle of the picture , I have circled it in blue .

Follow the wires connected to the transformer to locate the 24 VAC & power wires . Carefully test both sets for voltage .

God bless
Wyr

 

Wyr-I tested the blue and red wires and got around 7-8 volts. =\ I didn't test wires going to it. Won't be back home to test it until Thursday afternoon... I have the HVAC guy coming to look at it on Friday morning, since it's looking more difficult than changing the contactor.

Do you think I may need a new transformer? Just curious in looking at the costs before HVAC guy comes out.

 

You tested blue & red at the transformer ? Or where the cable is , with red , white , yellow , blue , orange ? and black and green wrapped around the cable jacket ?

Would be best at the transformer . You will have 2 - 24 VAC wires at the transformer and 2 power / line voltages wires . Or if it is a multiple voltage transformer ( 120 and 240 VAC ) , maybe 3 ( with only 2 connected ) .

You may have a fuse in either the power / line voltage circuit or the 24 VAC circuit . If you have a blown fuse , replacing the transformer may not be needed . There is a lot that can not be seen in then photos .

The " bottom " sheet metal panel is often where the furnace filter is located . There is usually a switch there , that must be closed by securely putting the sheet metal panel back in place / position . If that does not happen , the furnace gets no electrical power to its internal electrical components .

So , with the power off to the furnace , I recommend you cut the white plastic wire tye holding the red and blue wires at the " top " of the transformer . So you can separate the wires .

Find all the wires going to the transformer , both power / line voltage & 24 VAC . Test both sets of wires , power to power , then 24 VAC to 24 VAC , with your meter set on the appropriate scale .

I am reluctant to tell you to buy a transformer , at this point , unless you can easily return it , if you do not end up needing it .

If I was on site , I could test this in less time than it would take to type it .

Oh , look to see if you have a furnace control board ( may be a fuse on it ) or the individual components I see in the photo ?

God bless
Wyr

 

I tested the blue and red wire at the transformer and got 7-8 Volts. I removed the metal panel to the left of the transformer and found nothing back there... I was searching for a fuse. I thought if there is a transformer, often no fuse?

I actually ended up buying a transformer yesterday at Grainger. Can easily return. So I can have on hand with HVAC guy shows up. Here is a picture of everything...

 

Did you disconnect either the red or blue wire from whatever it's connected to before measuring the voltage? If it's easy to disconnect either wire (red or blue), I would suggest that you remeasure the voltage with the transformer "open circuit" (not connected to anything). It's possible that something is loading down the transformer reducing it's voltage output. Transformers don't normally give low voltage (open circuit). They either give the correct voltage (usually 24-28VAC), or nothing. Of course, anything is possible, so I'm not saying that your transformer is good, just that to be sure it's bad, you should measure the voltage without any load attached.

 

Did you measure to see if you have good power going into the transformer ? Should be 240 VAC in . ( Or 120 VAC , if that is the voltage coming to the furnace . )

Have you found the circuit breaker feeding the furnace ? Reset it . All the way off , then all the way on . It should be a single pole circuit breaker if the furnace is 120 VAC ( or 1/2 of a twin ) and 2 pole if it is a 240 VAC furnace .

You should also have a 240 VAC CB feeding the outside condenser unit , but it should be a different CB .

Is there a switch of disconnect at the furnace ? Fuses ?

God bless
Wyr

 

The yellow and black wires are for the condenser fan motor if I recall correctly.

.

 

Well, it turns out the compressor is dead. So was the transformer. Looks like I need a whole new HVAC unit. It had a good life of 26 years I suppose. Thanks for your help everyone.

 

Transformer is not a huge deal . but it would be good to know why it went out .

Compressor is a big deal . Also would be good to know why it went out . And if it was a burn out .

If you buy a new R410a system , I have been told that 16 SEER is usually about the break even point , as far as SEER goes .

God bless
Wyr