Heating, Air Conditioning, Fridge, HVAC/Heater


Hi Jim I replaced the capacitor and our heat worked great for almost two weeks. It is now doing the exact same thing as before. What should I do now?  I couldn't respond to your last answer so I have copied the conversation below so you will know what I have done so far. Thank you for your help.

QUESTION: "A few weeks ago our A/C stopped working. It is so close to fall and cooling down we have just been using a window unit A/C. This past week it has been pretty cool at night and we turned our heat on but it is only blowing out cool air. I can only get it to blow warm air if I turn it on Emergency Heat. Please help. We do not have the money to replace our unit due to my husband being placed on home dialysis and the many medical expenses that comes with it. I am pretty good at working on things and my dad is willing to help me. Again our unit is a Coleman EB15B Electric Furnace. Thank you for your help."

ANSWER: Hi Heather,

It sounds like you have a Heat Pump. What this means is the outside unit is your AC and your heat source. So when your AC stopped working a few weeks ago you lost both cooling and heating. When you set the stat to "Emergency" that brings on the electric strip heater in your furnace. These are very expensive to run.

So we need to find out why it stopped working. First thing we will do is set the stat switch to heat and turn the stat up to 78. Then go outside and see if the fan is running. Also listen to see if the compressor is running.

Then get back to me and let me know what you found.

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QUESTION: I turned the heat up to 78 and went outside. The fan is running and it sounds like the compressor is trying to come on but it doesn't.

ANSWER: Heather, That's exactly what I hoped it was doing. It sounds like you may have a bad capacitor. This is a easy fix but I have to warn you that there is 240 Volts inside. Make sure you turn off the breakers to the furnace and AC. You will need to get the MF ratings off the old capacitor. Probably be something like 35/5. I can go into more detail if you decide to do this.
Image: cap_2

---------- FOLLOW-UP ----------

QUESTION: Let me know what I need to do.  Thank you so much!!
Answer:   Heather,

First lets go over safety issues. The capacitor is like a battery, kind of, it stores power. So even with the power off it still have a charge in it. Normally I would test it with my meter. I don't think you will know any one that has a meter that reads MFD. So I think its worth trying to replace it.

1. Remove the cover and find the capacitor. There probably will be just one in there. In some cases there a two. Make note of the MFD ratings. Also see if it is round or oval.

2. Look on the top , each terminal will be marked. The terminals will be marked "herm", "fan" and "C". Note what color wires are on each terminal. Then go to motor-runcapacitorsonline.com. Don't remove any wires at this time.

3. Once you are ready to replace it, remove all the wires with  needle nose pliers. Next take a screwdriver and touch the terminals together. This will De-energize the cap and make it safe to handle. Make sure you put the right wires on the terminals. That's about all there is to it.

Let me know if you have any other questions.

Hope your husband is doing well.

Hello Heather, There is one more thing you can try. It is called a hard start kit. These are made for older compressors, as they age they become harder to start. This might get you a few more years out of it. The hard start has 2 wires on it. It connects to the "herm and c" terminals on the capacitor.

Let me know if you have any questions.

Heating, Air Conditioning, Fridge, HVAC

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Jim S.


I can answer questions on gas or electric furnaces, ac units and heat pumps. I don't work on boilers,chillers,or home appliances.


I have been in the HVAC trade for over 35 years. For the past 15 years I have owned my own business. I am semi-retired so I can answer questions in a timely manner.

I attended trade school for 5 years on weekends and evenings. This was very hard to do, but well worth it!

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