Starter kits for AC compressor

Question

An AC tech replaced a capacitor on my AC compressor. It cost 5X what I had paid for a generic capacitor, so when he mentioned that I would soon need some kind of starter kit I declined to have it done on the spot. Now that I am researching, a hard start kit seems to mean that it gives the motor an extra jolt to go ahead and get it started. A soft start would seem to be mean easing into it, but some info I find indicates that a "soft start" is actually an "extra-hard start."

If the AC compressor and fan are taking longer and longer to start, the change has been gradual. Now that I am troubleshooting why my lights dim when the AC comes on, it does seem that maybe there is a "drag" to get it started. Are either of these kits likely to affect the dimming, or are they strictly for the performance of the AC?

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The answers I have gotten so far on HISE have educated me a lot. I DIY whenever I can. My experience when I do have to call a tech of any kind is that they always insist that I buy their parts at their prices. Does this practice vary by region, or does it just depend on the guy?

Answer 1

My Gibson unit needed a starter kit almost from day one. My AC guy, who I've used for 30 years, put in one from SUPCO. Almost yearly, he would have to replace it, as the compressor wouldn't start. Had a new guy out for some other work and he suggested putting in a unit from Five Two One. It has been running strong for almost 5 years. The Five Two One unit has a relay whereas the SUPCPO does not. I ordered it in from Amazon for about $50.00 and he installed it in about 5 minutes. Just plugged in along side run cap. Depending on the age of your unit, you also may need to replace the run cap.

Answer 2

All the research that I've done can be boiled down to two main points:

1) Use the three wire kit - either the 5-2-1 or OEM kit if your manufacturer makes one. They have the potential relay which makes all the difference. Stay away from the two wire kits.

2) They are a good idea for both new and older systems.

I wish I had installed one on my Carrier system when it was new. Carrier actually makes an OEM kit for my HVAC. After I installed it on my twelve year old system I was amazed at how much easier it started and ran. When it's time to get a new system I will be installing a start cap with relay from day one.

Answer 3

I have the same situation; start shopping for a new compressor. I would say replace the whole outside unit ( compressor) and consider replacing the inside unit ( evaporator ) which may include the furnace. I replaced the start capacitor and the run capacitor and the "starter" kit last year. This year the AC tech ( who I trust) said it is not worth putting in another starter kit ; it may give another month or so of service. When my starter unit overloads , the computer shuts it down. For now I am able to disconnect all power for awhile, this erases the "error" message in the computer and it will restart. I have done this three times in a month, so the end is very near. Because your light dim ,it sounds like you need a new larger circuit for your AC. My unit is 5 ton (residential max) and it never dims lights ; has 50 A dedicated line. Actually your marginal power supply may be a big part of your problem.

Answer 4

Sounds like your "AC tech" is not telling you the whole story and jacking the price on the capacitor. Depending on your system you will have just capacitors or capacitors and a relay or current limitor. First, there could be one dual section cap or two caps for a start-run where the start cap is ALWAYS in the circuit. The second is a start-run where the start cap is switched off by either a relay or current limiter. This second system is usually repaired by adding a "hot shot" device (or whatever the locals call it) consisting of a cap and a relay. Probably can be had these days for about 40 bucks with instructions. There are variations of these two systems. You can tell if you can find a circuit diagram. And then ask more questions if the diagram snows ya!