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A/C hard start capacitors [message #357773] Mon, 17 August 2020 11:22 Go to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Senior Member
I am still not having the best of luck staying cool in the coach, but it is getting better.

Long story- but me and generators don't seem to get along. My 6000w onan has a bad field coil. I could not get a ev6010 honda to work for me.
So I went to a 2800 onan microlite, and that one is now not working.

I currently have a ef2200is on the bumper, but even that one quit and spent a month at the dealer getting a new coil pack assembly installed under warrantee.

I am having issues with the ef2200is getting along with the Air conditioners.

I am running an atwood air-command up in the front hole- 15500 btu version with the heat pump. and I have a oem dometic in the back hole.

the OEM one does not get along at all, witch is expected on start up. I did and really do not expect it to run off the yamaha.


the atwood air-command on the other hand I would think it would, and it has always been working great. I have metered it and it usually runs at 7-8 amps, but I do not have a good enough meter to measure the surge, and that seems to be the issue with the yamaha, but only on hot days and not consistant. I can bench test and run it for hours at home, but on the road when it is hot and you need it to work, it has been inconsistent.

I have ran the atwood on honda 2000. and always seemed to work under testing conditions. but I learned that heat and humidity changed the whole equation.

I actually had it running the fan only and the air-command runs, but it will quit turning on the compressor so all you get is fan. I thought my A/C had quit until I switched to shore power and it started blowing cold again.

it is not an all or nothing thing.

So while I am trying to diagnose the true issue with the onan, (part is $300- so I want to make sure that it is bad!!). I am thinking of a hard start capacitor for the atwood. The atwood I thought had one built in, but it is hard to tell in the literature, and if a hard start capacitor would help either way.

I am also going to buy/install one in the dometic, maybe it won't help, but for $30 it can't hurt???

I did dive into the atwood a little yesterday and oiled up the fan motors, and made sure the coils were all clean.


So has anybody had experience? I see some hard start capacitors for like $30. and there is a "micro-air" one that is like $300. the micro-air one I did find someone that did install one on an atwood and was happy with results.

once get my onan 2800 back working, this might not be an issue, but if a hard start compressor makes things work better on the onan 2800, then it is all good. I still hope to be able to utilize the yamaha ef2200is when boondocking and A/C is needed, rather then the onan that is right under the bed.







Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: A/C hard start capacitors [message #357775 is a reply to message #357773] Mon, 17 August 2020 15:10 Go to previous messageGo to next message
pjburt is currently offline  pjburt   United States
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Registered: February 2016
Location: Fresno, California
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Senior Member
Jon,
You might want to take a look at a SoftStart. It allows you start an a/c with as low as a 20 amp service.
https://www.rvtravel.com/softstart946/
Jerry


Jerry Burt Fresno, CA.
73 Gmc 26' Canyon Lands
Members: FMCA - GMCMI - GMCWS
A truly happy person is one who can enjoy the scenery on a detour.
Re: A/C hard start capacitors [message #357778 is a reply to message #357775] Mon, 17 August 2020 15:30 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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interesting. almost the exact same product as the micro-start I was looking at.


https://www.microair.net/products/easystart-364-3-ton-single-phase-soft-starter-for-air-conditioners?variant=30176048267


I did order two of these today:

https://www.rv-ac.com/RV-AC-Hard-Start-Kit.html





Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: A/C hard start capacitors [message #357779 is a reply to message #357773] Mon, 17 August 2020 15:33 Go to previous messageGo to next message
Matt Colie is currently offline  Matt Colie   United States
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Jon,

If you want to get the NH (6K) Onan back on line, contact James Miller in Hamilton OH (in the roster) he has rewound more than a few. It is not a cheap operation, but the machine then has copper winding that will not corrode away.

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
Re: A/C hard start capacitors [message #357780 is a reply to message #357779] Mon, 17 August 2020 15:52 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
Messages: 2324
Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
It might come to replacing the onan.

I had it running pretty good before the field coil corroded and wire failed in that. had bovee ignition, good muffler, had all the seals replaced, de-carboned it, had new mounts.


but now I have had too many people with onan issues come near me. Mine is 1/2 parted down. I do have access to other onans if I do decide to go back that way, but now my compartment is all different, it would take a bunch of work again to get back to the power drawer, to re-do the 110v cables, the 12v cables, ect.. but never know.


The onan 2800 should be a good unit. it physically looks in great shape. I know others that run it, and are happy. But that statement is the same for the honda ev6010 that never ran more then a couple hours after I left my driveway for me before it left me cooking inside the coach.

I am more the common problem then the generator is. especially when the new yamaha quit. I figured for $1000 and a warantee I would be good. but no one can fix a new generator in in a short amount of time. Cherish the old onan troll.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: A/C hard start capacitors [message #357781 is a reply to message #357778] Mon, 17 August 2020 15:53 Go to previous messageGo to next message
pjburt is currently offline  pjburt   United States
Messages: 436
Registered: February 2016
Location: Fresno, California
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Senior Member
lqqkatjon wrote on Mon, 17 August 2020 13:30
interesting. almost the exact same product as the micro-start I was looking at.


https://www.microair.net/products/easystart-364-3-ton-single-phase-soft-starter-for-air-conditioners?variant=30176048267


I did order two of these today:

https://www.rv-ac.com/RV-AC-Hard-Start-Kit.html

Certainly worth giving them a try for the price.


Jerry Burt Fresno, CA.
73 Gmc 26' Canyon Lands
Members: FMCA - GMCMI - GMCWS
A truly happy person is one who can enjoy the scenery on a detour.
Re: A/C hard start capacitors [message #357788 is a reply to message #357775] Mon, 17 August 2020 21:16 Go to previous messageGo to next message
Rick Staples is currently offline  Rick Staples   United States
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Registered: May 2014
Location: Johnstown, Colorado, USA
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Senior Member
Jerry wrote:
"You might want to take a look at a SoftStart. It allows you start an a/c with as low as a 20 amp service."

FWIW, I used to run one original Duo-Therm A/C on a 15 amp circuit when parked in my driveway. No SoftStart required. I have run BOTH original Duo-Therms on a 30 amp connection also with no problem, other than the campground manager bawling me out. In both cases, just had to be sure NOTHING else was running on the same circuit.

OTOH, I don't think you'll be able to run 2 A/Cs on a generator much under 4,000 watts, and if they both try to start at once, something's gonna pop.

My 2¢
Good luck
Rick Staples


Rick Staples, '75 Eleganza, Johnstown, CO "Advice is a dangerous gift, even from the Wise to the Wise, and all paths may run ill." -Tolkien
Re: A/C hard start capacitors [message #357802 is a reply to message #357788] Tue, 18 August 2020 10:45 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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Registered: August 2015
Location: DFW
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Senior Member
Rick Staples wrote on Mon, 17 August 2020 21:16
Jerry wrote:
"You might want to take a look at a SoftStart. It allows you start an a/c with as low as a 20 amp service."

FWIW, I used to run one original Duo-Therm A/C on a 15 amp circuit when parked in my driveway. No SoftStart required. I have run BOTH original Duo-Therms on a 30 amp connection also with no problem, other than the campground manager bawling me out. In both cases, just had to be sure NOTHING else was running on the same circuit.

OTOH, I don't think you'll be able to run 2 A/Cs on a generator much under 4,000 watts, and if they both try to start at once, something's gonna pop.

My 2¢
Good luck
Rick Staples
As mentioned, this is all dependent on ambient temps... Temps go up, the running pressures of the refrigerant inside the AC go up. A compressor running at higher pressures will use more power to do it...


Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: A/C hard start capacitors [message #357993 is a reply to message #357773] Sun, 23 August 2020 20:14 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
Messages: 2324
Registered: October 2010
Location: St. Cloud, MN
Karma: 5
Senior Member
I just climbed up on the roof and installed the hard start capacitor on both the atwood air command and another on my old duo-therm.

The atwood had no room, so had to adjust the electrical door to allow it to fit. It seems to be running a little different, I am not sure if this is throwing off the thermostat, but it is not cycling constant like it used to. The atwood uses a control board and it does not operate like most a/c’s so it is hard
To see exactly what it is doing. It has 2 fans and a compressor. And all start up at different times and it is pretty quiet.

I only ran it for about 10 minutes as it is 8pm and have other things to get
Done before i go to bed.


The original duo therm. That hard start seemed to quiet that old noisy sucker up. No more definitive noise when the compressor kicks in. I wish i had
Installed
This
Hard start
On it 10 years ago
It if this is the case. It was simple
To install. Just goes in parrallel
With the existing capacitor.

But again I am not drawing conclusions on these. Further testing needs to be done.



Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: A/C hard start capacitors [message #358003 is a reply to message #357773] Mon, 24 August 2020 09:04 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Registered: October 2006
Location: Woodstock, IL
Karma: 12
Senior Member
Hard start and soft start are two different animals. Hard start is bigger cap to try to start a tired compressor or overcome spongy power situation and get more service out of an older unit. Soft start uses SCRs to ramp up voltage over time. There are lots of videos on line. https://youtu.be/15wD70M58fM

John Lebetski
Woodstock, IL
77 Eleganza II
Re: A/C hard start capacitors [message #358007 is a reply to message #358003] Mon, 24 August 2020 10:28 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Senior Member
thanks John.

that explains why one is $22 and the other is $300.

I installed a "hard start" capacitor. What I am trying to fix is the spike that is not agreeing with the generator.

Generator is a 2200 watt max, 1800 watt rated output, that should be 15 amps.

the atwood air command is rated at full load cooling at 13.9 amps. if you put a clamp meter on it when running, it usually reads 7-9 amps.

so the spike at compressor start up, is basically not starting the A/C compressor when ambient temps are starting to reach 90 degrees. it seems to me, the A/C unit does not recognize that and the fans still blow like crazy, and there are no error codes. Fans just blow and you have no cooling out of the A/C. so I am hoping this "hard start" will help take care of that, and the A/C will pump some cool air running off the yamaha 2200is generator when it gets hot out and is needed.

problem is there is a possibility that I may not see the 85-90 travel temps until 2021 now to really test it out.







Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] A/C hard start capacitors [message #358008 is a reply to message #358007] Mon, 24 August 2020 10:52 Go to previous message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
Don't forget, the delayed compressor start built in to the DuoTherm AC
unit. Mine takes 2 minutes sometimes before the compressor kicks in. It
makes the generator twitch the governed speed momentarily due to the start
load on that big compressor. I now know that is a normal occurrence.
Concerned me quite a lot when we first got the coach. Don't even notice it
now.
Jim Hupy
Salem,Oregon

On Mon, Aug 24, 2020, 8:28 AM Jon Roche via Gmclist
wrote:

> thanks John.
>
> that explains why one is $22 and the other is $300.
>
> I installed a "hard start" capacitor. What I am trying to fix is the
> spike that is not agreeing with the generator.
>
> Generator is a 2200 watt max, 1800 watt rated output, that should be 15
> amps.
>
> the atwood air command is rated at full load cooling at 13.9 amps. if
> you put a clamp meter on it when running, it usually reads 7-9 amps.
>
> so the spike at compressor start up, is basically not starting the A/C
> compressor when ambient temps are starting to reach 90 degrees. it seems
> to
> me, the A/C unit does not recognize that and the fans still blow like
> crazy, and there are no error codes. Fans just blow and you have no
> cooling
> out of the A/C. so I am hoping this "hard start" will help take care of
> that, and the A/C will pump some cool air running off the yamaha 2200is
> generator when it gets hot out and is needed.
>
> problem is there is a possibility that I may not see the 85-90 travel
> temps until 2021 now to really test it out.
>
>
>
>
>
>
> --
> Jon Roche
> 75 palm beach
> EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
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