# Hard Start Kit/capacitor



## bradnbecca (Feb 12, 2007)

Anybody here installed a hard start kit on their A/C? I want to put one on my 15k BTU unit to give it a little help when using my generator (we travel with dogs and would like to be able to cool off the trailer if we decide to stop and eat or explore a non pooch-friendly place).

I am wondering where you put the new capacitor? Is ther room adjacent to the starting capacitor, or did you have to find another place to put it? I am assuming that it is a relatively easy job- just two wires to the starting capacitor, right?

Any input/guidance would be greatly appreciated.


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## CamperAndy (Aug 26, 2004)

The hard start or soft start (depending on who you ask) is often a replacement for existing starting cap but it depends on the AC manufacture on if you wire it in parallel or as a replacement. Either way it is a 10 minute job. Takes longer to take the cover off then replace the capacitor.


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## N7OQ (Jun 10, 2006)

The Hard starts I use connect in parallel with the starting cap. My AC unit has a double capacitor with 3 leads a common lead "C" and fan lead "F" and a compressor lead "H" not sure if the 15k is the same but if it is than make sure you connect the hard start between the "C" and "H" leads. The hard start has a ha capacitor and circuitry inside to take it out of the circuit after the start they are not a replacement but a addition to the starting cap.

A soft start is a whole different animal we use them too. They are used on motors to allow them to ramp up slower so they don't over torque the mechanical equipment. You can not use a soft start on a AC compressor it will not work at all, would make it worse.


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## aplvlykat (Jan 25, 2004)

I agree the hard start kit or super boost setup wires in paralell with the H(hermetic compressor) and the C( common), it plugs right on. I never liked this dual capacitor setup(all in one) because they have a tendency to burn out quicker then the double capacitor(seperate) set-up. If you have the room replace all three, fan cap, compressor cap and super boost. The rating will be on the dual cap something like 30/5 mfd just make sure you also get the correct voltage rating which will also be listed. Haven't done this yet but it is on the list before summer hits. Kirk


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## bradnbecca (Feb 12, 2007)

The a/c is a 15k Carrier. It appears from looking at the manual online that the capacitor is a two way, so I will connect the booster to the common term and the her terminal.

The a/c has not been used in a couple of weeks and is not hooked up to any power source. Do I need to discharge the capacitor on the a/c before I attach the booster cap, or should it already be discharged ?

I am not worried about getting electrocuted, but getting a jolt and getting knocked off the roof would suck big time . . . . .


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## CamperAndy (Aug 26, 2004)

Better safe then sorry, Always de-energize and discharge caps before working on them.


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## bradnbecca (Feb 12, 2007)

Well, I climbed up on the roof and hooked it up last night. The only difficulty I encountered was that there was no open post on the common terminal. Thankfully, the Supco capacitor comes with a "piggyback plug" on one leg, so it was just a matter of doubling up on one lug.

It seems to work just like it is supposed to. The weather was warm and muggy last night, and the a/c fired right up on generator power, without boggin or hesitating at all. I hope it will function this well when it is really hot out, but so far so good.

Thanks to all for the help. :







:

BTW, I evicted quite a few spiders and a couple of yellow jackets from the shroud and the coils- they were less than thrilled . . . . .


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## 04SUPERDUTY (Jul 3, 2006)

where did you get the hard start capicitor from and how much was it?? did you need to de energize the existing capicitor?


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## map guy (Jan 11, 2007)

04SUPERDUTY said:


> where did you get the hard start capicitor from and how much was it?? did you need to de energize the existing capicitor?


X2 here.

Looked throught the Carrier manual and searched a bit but no real luck. This is not an area of knowledge for me.

Map Guy


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## bradnbecca (Feb 12, 2007)

The "kit" is actually a capacitor/relay combination that is not just for RV air conditioners. Every one I have seen/found was made by a company called Supco. I got mine at an air conditioning supply house close to where I live. Just tell them you want a hard start kit and they will know what you are talking about. Just make sure the one you get is for 110v systems and not 220.

here is a link to a supplier in Dallas that shows what they look like:

http://www.kg-ind.com/hard_start_kit.htm

As far as discharging the capacitor, yes I did. It probably was not holding a charge, but there is no way to know by looking at it. It probably doesn't store enough to kill you, but when you consider that essentially all it is there for is to store enough of a charge to fire off a compressor, it could give you enough of a kick to really mess up your day, especially when you consider that you are perched 12-13' above the ground.

Discharging the cap is relatively easy using a screwdriver, as long as you remember to keep your hand on the insulated part. I actually used a screwdriver with a jumper wire attached, which makes it a little easier to reach a ground.

I paid about $24.00 for the one I got.

BTW- I got the STT6, because that is what the A/C guy at the supply house told me would work best for me.


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## map guy (Jan 11, 2007)

Thank you!

Map Guy


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## 04SUPERDUTY (Jul 3, 2006)

thanks for the info


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