I didn't say it was a hard start but in the video they show the difference between a factory start cap and hard start kit that's why I mentioned it and like I said hard start devices are junk. Like I said their measurement of start current in their video is misleading because they are starting the fan motor and compressor at the same time that's not normal if it's cycling on the thermostat. One other thing not to do if your running off a small generator is don't turn the thermostat on before the generator is up and running because the thermostat and control board runs off the trailers 12v system and it has no idea if the 120v is at the unit so all the time delays have timed out if you put 120v power to the unit latter.

Split phase motors are designed and wound at the factory to run on a run cap they size and start caps that are sized for the desired starting torque. When they say they ramp it up that tells me they are playing with the start winding current by varying the capacitance. The capacitor changes the phase angle for the start/run cap winding creating the rotating magnetic field that turns the rotor, the greater the phase angle the higher the starting torque to a point. If you ever looked at a split phase motor you would see that the run windings are heavier than the start winding and start windings draw a fraction of the run winding current when running. The factory sizes the start cap to start the motor as fast as possible getting the motor up to speed and build up inductive reactance or induced resistance in the motor windings lowering the current draw. When you slow the motor startup it will draw higher current longer through the start windings that they aren't designed to have and over time it can be damaging to the start windings.
If you want a true soft start compressor get a variable speed but that's a whole different animal, they are out there and are becoming popular.

I've worked on 1000s of single phase compressors and watched the winding currents with a analog amp probe not a digital to troubleshoot them when they wouldn't start and run and watched the current reading change when I didn't have the right size cap to get it going. The units I worked on ran 24/7 365 so they had to work as designed from the factory and I found one size fits all aftermarket starting devices didn't hold up over time.

Denny

 

Are you claiming their soft start is not a soft start? A VFD is a possible solution but not needed when a soft start does the job.

Based on the positive reviews of these soft starts I think they work as advertised and will be looking to add these to my new RV that has two AC units.

 

I never said it wasn't a soft start, anytime you introduce a start cap to a single phase motor it softens the start by starting it faster building magnetic resistance faster. What I call BS on is the video were he started both the fan motor and the compressor at the same time drawing startup current at the same time dropping the voltage, when the voltage goes down the amperage goes up so delaying the compressor starting then taking the amp reading using their device isn't a fair comparison.

I would think long and hard before I installed one on a brand new unit still under warranty, instant voiding of the warranty but that's your choice.

I run ours off our generator all the time but we have one big enough to do the job. If you want to run one off a small generator first make sure you frig is locked on to gas and unplug or turn the breaker off for the converter. Our unit also delays the compressor coming on after the fan motor but I have no idea if newer units do the same.

Denny

 

It seems to me they would start the fan and compressor at the same time to illustrate worst case scenario. And if the unit is really just a capacitor, it's not a soft start - a cap would help motor starting by preventing voltage drop so the motor could start normally, though that is not what a soft start does. Real soft starts (used in industry all the time) ramp the voltage and current to start a motor slower. This is critical on large electric motors with high rotating mass that can't be spun up instantly.

 

Whatever it is or should be called, in our opinion it was worth the cost of admission. We noticed a big difference in the noise level (thunk sound) when the compressor turns on even when hooked to shore power. As well as being able to run the AC and converter with our iGen 2500 Westinghouse suitcase generator with a tri-fuel conversion kit.

To each their own and I have been known to buy stupid crap in the past, at least this one makes a difference in comfort, sound and versatility.

 

I will disagree with your take on the test, for a true comparison it has to be apples to apples not apples to oranges.
And yes large industrial motors ramp up to limit voltage drop and current surge, the large (30+ HP) refrigeration compressors I worked on were 3 phase and had two contactors each running it's own set of windings. The first contractor ran smaller gauge windings with more resistance that would limit current to get it started and the second contractor winding were larger gauge wire to run it at full power. Both windings stayed in but the smaller gauge windings limited the current so they wouldn't burn up. If they are doing what I think they are doing with the start winding the small split phase motors aren't designed to be started that way.

Denny

 

Not sure what video or comparison you are referencing but if there is an unfair comparison, I agree they should fix the video. However, these units are well proven to do what they say they do (both popular brands) and they do not need an unfair comparison to demonstrate they work. Mine certainly do and I tested them to ensure they meet their advertising claims. There are likely 10s of thousands of these installed if not more (20,000 Micro-Air as of 2019, does not included SoftStartRV) . I have never heard of one that did not work as advertised when properly installed. I have also never heard of one damaging a compressor motor or anyone being denied a warranty claim because they used one on their unit. Micro-Air and SoftstartRV even provides a free warranty that matches the AC manufacturers warranty in the event that the manufacturer denies warranty so either way the customer is covered. I can't find any reference to anyone ever having to exercise that warranty.

Being able to run one or more AC units on much smaller generators and the ability to run two AC units on 30 amp service has been a huge benefit to the RV community over the years.

 

I’m also thinking about adding soft starts to my three a/c units . My generator will handle all three fine as is . I think they may prolong the life of the compressor’s starting slower . I too worked in commercial buildings and had soft starts on pumps , air handlers and other equipment. Not only did they help with the inrush current surge they helped with prolonging belt and bearing life . Also had VFD drives on chillers and air handlers that help save wear and tear on the equipment along with saving energy.

 

My experience is with 3 phase 480v and 4160v motors running pumps, fans, and compressors 100 to 1000HP. So no experience with single phase.
As to the video, he's comparing start current without and with the product they are selling. Sure, if you delay compressor start it will drop the current but the units don't do that from the factory, so why should they handicap the benefit of the product they're selling?

 

__________

 

Any updates to this thread? I'm looking at a Soft Start for my camper.

 

I installed my Micro-Air Easy Start a week or so ago. I'm putting in a new Coleman Mach 15 so I did the install of the Easy Start while the air conditioner is sitting in the bed of my truck. Install was very easy. Now I just need to get the air conditioner up on the top of the camper.

 

They offer a FREE extended warranty- of course for the "scaredy cat's" you gotta give them you name and address...


Some RV owners feared that their installation of an EasyStart 364 might in some way void the manufacturer´s warranty on their rooftop AC unit´s compressor motor. That is 2 years for Coleman and Dometic models. Legally, it shouldn´t. But you never know what a manufacturer might assert. Micro-Air is quite confident that its product cannot damage your compressor so we “extended” our warranty to your compressor. And you don´t need a NEW compressor to enjoy our Double Down protection.

You can google the Magnuson-Moss Warranty Act and the voiding of warranties for adding an aftermarket part. The aftermarket part needs to have a causal effect to void the warranty.

Micro-Air offers a FREE Extended Warranty, worry no more! Please reference our EasyStart™ 364 RV Rooftop Soft Starter Double Down Extended Warranty for more information and coverage. If purchased, this Extended Warranty shall create certain rights and duties between the parties which shall be in addition to and shall not be exclusive of the Limited Warranty appearing on the Company website.

 

Maybe you should talk to Microair and learn how to unit actually works as opposed to implying that they will hurt your compressor and/or the Easystart is no good since it's universal and works on multiple units... Mine has had one on it since 2016 and been used in the hot Texas summers.... A/C and Easystart are still working..

Hard data good enough for you?

 

I installed the EasyStart 364 (Bluetooth) a couple weeks ago in a new Coleman Mach 15, which was put on the camper yesterday. The EasyStart was the easy part. The learn process was very easy too. The Bluetooth wasn't necessary for the learn process, which was good because I couldn't get the app to connect due to a permissions error that I wasn't aware of until later.

I don't know if it's just because it's a totally new air conditioner or if it's the EasyStart, but I didn't hear the compressor kick in once during the relearn.