Soft Start Pack for AC units

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prolong the life of your compressor

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This is one of the single worst claims I have ever seen.
If you need one to soften asynchronous startup currents so it will start on a weak generator or inverter, it could be useful for that. Extend life? Absolutely not. Maybe if you had a habit of running it to full temp and immediately starting and stopping it like a thousand times. I don’t think that is realistic. The insulation cares about temperature, not current. Inrush is a short enough period not to cause a lot of heat and isn’t usually applied to a hot motor anyway. Startup torque is already weak so there’s no need to soften anything mechanically. Also, your refrigerant isn’t even compressed yet at this point.

I bought a hyper engineering soft starter for the following reasons:

It's small enough to fit inside the covered panel on the unit

I installed a interlocked generator inlet

The compressor would dip the lights when it kicked on

No more lights dipping and I can start the compressor on a 7000W run 9000W start inverter generator converted to natural gas

I have the one from micro-air and it works for reducing startup load.

They are one of the few products still made in the US by a small private company.

As to the claims of extended compressor life, I can't confirm. But it sure can't hurt. Like many, I bought it to allow my generator setup to start the outside compressor when running off-grid (yes I have a code compliant disconnect at the main to prevent backfeeding the utility).

Here's a writeup I did years ago about the Micro Air soft starter. Been using for almost 3 years and near 30,000 starts. You gain a new respect for your compressor when you realize how many times it runs during the hot days.

LINK

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Extend life? Absolutely not.

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I think a case could be made that it extends motor life and the article below gives some good reasoning. I think the benefits would be more apparent on an old reciprocating compressor rather than a scroll compressor since there is more inertia at play. And a larger motor with a very high LRA would benefit from a soft starter by not putting so much heat and torque on the windings of the motor getting hit. Heat is generated by current and the higher the current slapping that motor the more heat is generated.

LINK

Do I think it can considerably extend compressor life? Maybe, but I see that as more of a secondary benefit of using the soft starter. Personally, I love the unit even without considering it just for my generator. It starts very quietly, it runs quieter overall, and doesn't dim the lights in the house when it kicks on. All of those have been awesome benefits.

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Ideally the worst thing that could happen is a normal start except for maybe the ones that completely bypass the run cap.

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I had a Micro Air unit fail and was quickly replaced by the manufacturer under warranty. I couldn't connect via bluetooth so I went outside and saw the compressor starting as if the soft starter wasn't there. So I'm not sure if it's designed to bypass during failure but that's what happened to me.

That said, the manufacturer told me the biggest enemy of these things is sunlight so I just stuck them in a simple outdoor NEMA-rated enclosure. And one of my soft starters has almost 30,000 starts on it.

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or any significant energy savings like some of the claims.

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I doubt this is ever seen since the inrush is such a short duration. In theory it could save energy but in the real world it's negligible.

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Search this board for "MicroAir" or "EasyStart"

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Can vouch for Micro-air.. Been on my 5 ton unit 3 years and no issues. Can startup on 10,000 generator. Once it starts I turn thermostat down to 55 so it won't cycle.

Years ago most ac units came with a soft start from the factory. As ac's became more efficient they were fazed out do to reduced draw on the newer motors. A soft start can reduce amps needed by up to 60%. The reduced amperage is stored in the soft starter. It reduces the amps needed and the duration of the start. Despite mixed opinions, HVAC repairmen use soft starters to extend the life of older units and generally believe them to extend the life of the units. As others have reported, they are very helpful when used in conjunction with generators. It plugs into the capacitor so it's like a battery boost for lack of a better analogy.