Soft start for AC

SiniWisdom · 07-18-2020, 06:36 AM

I recently purchased a propane generator for my 2018 Cougar 25RES fifth wheel. It runs 3,000 at peak and 2,700 watts continuous. I wanted to get a soft start for my AC but my RV tech said that the Cougar has that built in. Here is what he said: "Under the shroud of the AC, there are 1 to 3 capacitors. The newer units have only 1 that does the job of all 3. The original 3 were 1 hard start, 1 soft start, and 1 starter for the fan. Your (my) AC is already equipped with a soft start. I'm not sure how many yours has, but the 1 does the same job as all 3 so either way you are covered. And it goes based off of the incoming power so it will automatically select the best choice".

Does this sound right? Because the soft start manufacturer seems to think mine is more a "hard start kit". Granted, he does want to sell me the unit, but his opinion makes sense also. Any thoughts that could help a girl out? And if so, please dumb it down for me. Thanks!

KRumm · 07-18-2020, 06:42 AM

You have the generator... Just plug it in and see if the AC starts... One thing you need to do is turn off the built in converter/battery charger at the fusebox as it can draw a lot of amps if in charge mode...

wiredgeorge · 07-18-2020, 06:46 AM

Don't know about current A/C capacitors and would tend to pay attention to that tech who probably is... a house A/C has a run capacitor and a start capacitor and soft start capacitors are an add-on. I added one to ouir currect A/C (house). You might want to fill us in our make/model of the A/C on your camper. Someone here may have the same unit and know the answer. It also helps to put your year, make, model and tow vehicle info in your signature in the event other questions arise in the future! Good luck... not sure how much propane a generator uses... I have a gasoline/propane generator but have never used it in propane mode. It is what the generator snobs call a construction type generator and it does make some noise so isn't suitable for rv parks most likely.

**chuckster57** · 07-18-2020, 06:54 AM

Some newer RV's are coming with Roof air that has "soft start" integrated in the unit. To verify if this feature is in fact included in YOUR unit, I would get the model and serial number and check with the manufacturer of the AC unit.
I have met too many "tech"s that say they know a lot and in reality know nothing..I think its a product of needing to feel/appear "smart". I have NO ISSUE saying I don't know, but I also say I will find out for sure.

SiniWisdom · 07-18-2020, 07:05 AM

Do I need to get on the roof to find the model & serial#?

**chuckster57** · 07-18-2020, 07:11 AM

Quote:

Originally Posted by SiniWisdom

Do I need to get on the roof to find the model & serial#?

That might be the quickest way if you don't have the owners packet that will have the warranty tag for the AC unit with the model and serial numbers.

**flybouy** · 07-18-2020, 08:19 AM

That's a lot of fifth wheel for a F150. I know they call it a "1/2 ton towable" but all 1/2 tons are not created equally. Do you know what the door sticker in your truck reads? The part that states "all passengers and cargo shall not exceed xxx lbs.?

travelin texans · 07-18-2020, 08:50 AM

Quote:

Originally Posted by KRumm

You have the generator... Just plug it in and see if the AC starts... One thing you need to do is turn off the built in converter/battery charger at the fusebox as it can draw a lot of amps if in charge mode...

Second to running the air conditioner keeping the batteries charged would be the next reason for using a generator so why would you turn that OFF.
By turning the converter off the batteries will die, with no battery to power the controls you'll have no hot water, no fridge, no furnace, no ac, regardless if running on gas.

ChuckS · 07-18-2020, 09:52 AM

Sorry to say but the RV Tech doesn’t have a clue of what he is talking about regarding your RV AC units...

You either have the Coleman Mach 3 or Mach 15 series unit or Dometic Brisk Air 2 series AC units installed...

IF they came with the optional PTCR installed then theoretically you have what is called a soft start... provided it actually does what it’s supposed to

Here is a read explaining what a PTCR is and is suppposed to do ....

http://www.tiffinrvnetwork.com/crusingator/P/P-090.pdf

First pic is from Coleman’s advertised specs...

According to Coleman’s brochure the Mach 3 and 15 come standard with a PTCR circuit

If I was going to enhance my RV AC unit start ability the only route I’d consider is the Microair unit....

https://www.microair.net/products/ea...nt=30176048267

ChuckS · 07-18-2020, 10:19 AM

This is also an excellent read and should clarify your questions regarding soft start...

a single generator of 3000 watts is gonna be hard pressed to start and run the AC unit, run the converter, etc without the engine gutting itself running at better than 75% load with AC and converter running... you need the converter on to maintain the batteries and provide !2vdc power to the AC control box modules.. without 12vdc the AC unit will not run

https://www.rvupgradestore.com/v/vsp...ily_RV_ACs.pdf

this is also a good read to clarify generator power requirements

https://www.steadypower.com/pages.php?pageid=133

wiredgeorge · 07-18-2020, 12:44 PM

ChuckS, the link that you provided has that MIcroair gizmo claiming you can:

Run 2 air conditioners on a 30-Amp cord. (Note: Each A/C requires an EasyStart unit)

How is this possible if an A/C uses 12-16 running amps? Seems to me that if you turned on anythiing else 117V you would blow your breakers.

tech740 · 07-18-2020, 07:11 PM

You can run two A/C’s on 30 amps. I am doing it as I type. I have a residential fridge and water heater on propane. I staggered them when they start and they are pulling 13amps each according to my EMS. PS the daughter turned the coffee maker on and blew the breaker earlier. It can be done though.

KRumm · 07-18-2020, 09:45 PM

Quote:

Originally Posted by travelin texans

Second to running the air conditioner keeping the batteries charged would be the next reason for using a generator so why would you turn that OFF.
By turning the converter off the batteries will die, with no battery to power the controls you'll have no hot water, no fridge, no furnace, no ac, regardless if running on gas.

Agreed turning off the battery charger has a cost... But the OP has a ~2,700w generator and wants to power a 15k air conditioner... A typical converter charger will consume 700-1,000+ watts of power leaving little power to run the AC - Even it’s a soft start... Run the generator a couple hours in the cooler morning to charge the batteries then in the afternoon run the AC (without the charger on)...

**chuckster57** · 07-19-2020, 03:53 AM

Quote:

Originally Posted by tech740

You can run two A/C’s on 30 amps. I am doing it as I type. I have a residential fridge and water heater on propane. I staggered them when they start and they are pulling 13amps each according to my EMS. PS the daughter turned the coffee maker on and blew the breaker earlier. It can be done though.

Residential fridge on propane?

Bill-2020 · 07-19-2020, 07:58 PM

Quote:

Originally Posted by chuckster57

Residential fridge on propane?

I was also going to say, ??? But I think they meant they have a residential fridge and the water heater is running on LP, not both on LP. Just a guess...

tech740 · 07-20-2020, 11:45 AM

Yup res fridge on power and water heater on propane.

Bill-2020 · 07-20-2020, 02:37 PM

Quote:

Originally Posted by tech740

You can run two A/C’s on 30 amps. I am doing it as I type. I have a residential fridge and water heater on propane. I staggered them when they start and they are pulling 13amps each according to my EMS. PS the daughter turned the coffee maker on and blew the breaker earlier. It can be done though.

Just thinking here- sooner or later those two units, even though they were started staggered, will cycle off and then both will attempt to start at the same time. That won’t fly. Chances are slim of course, but Murphy May drop in for a visit one day.

**flybouy** · 07-20-2020, 03:21 PM

Running 26 amps is running at about 86% of that 30 Amp breaker. With a 4 Amp reserve I don't see how you could have the converter charging the batteries.

tech740 · 07-20-2020, 04:50 PM

It may not have been charging the batteries. But for the two hours that both were needed to keep the cabin where I wanted it, we had no issues. I understand running both for days on end will not do the the job. But, for a couple hours to keep the hottest part of the day at bay, or for a quick cool before going to bed and the sun goes down it serves its purpose.

ObiRich · 07-26-2020, 10:34 AM

Quote:

Originally Posted by SiniWisdom

Does this sound right? Because the soft start manufacturer seems to think mine is more a "hard start kit". Granted, he does want to sell me the unit, but his opinion makes sense also. Any thoughts that could help a girl out? And if so, please dumb it down for me. Thanks!

Why not contact the manufacturer of your A/C and find out straight from the horse's mouth?

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