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Title: Coleman AC Woes
Post by: luvrbus on July 30, 2021, 07:30:57 AM
I have 2 of my Coleman Mach 8, 15,000 btu with heat pumps and condensation pumps that are drawing 26 amps what should I check. I have changed all the caps (start,run and fan) in ea.I would like save some money instead of replacing 2 units @$1200.00 ea any ideas.If the compressor is the problem I will change out the units Coleman want $600.00 for the compressor alone,So how do you check the compressor ? Mine are model 47024B676 lol just my luck they are not your average Coleman   

thanks
Title: Re: Colemaa AC Woes
Post by: dtcerrato on July 30, 2021, 07:44:28 AM
Your Coleman will probably out perform our Dometic 13,500 Brisk Air Ii but we swear by that particular unit as it is the highest efficiency roof air on the market. Sells at under $1000 and draws a whopping 9 amps running. Our inverter runs one at 950W 12vdc. Two units can be run on a 30A circuit. We've always only had one unit on our 04 & it does a decent job.Just an option fwiw.
Title: Re: Colemaa AC Woes
Post by: luvrbus on July 30, 2021, 07:52:12 AM
Thanks Dan but mine are ducted and being 13'2" tall I have to stay with the low profile and all 3 work off 1 thermostat with zones setting,when working right they run on 13 amp up to 15 amps depending on temperature   
Title: Re: Colemaa AC Woes
Post by: lvmci on July 30, 2021, 08:18:56 AM
Hopefully Nick Badame will pop in with advice...
Title: Re: Colemaa AC Woes
Post by: freds on July 30, 2021, 10:22:01 AM
After decades in the computer industry I absolutely hate fan noise!!!

While I want an efficient air conditioner a quite one is really, really high on my priority list.

I understand that ducting can help in this regard. To the point that I am considering some experiments Carrier Air V units that I have now.

Mine is the older version with a compressor and fan motor that drives the internal airflow squirrel cage fan and the condenser fan off of the same shaft. Newer ones have two fan motors.

Thinking removing the internal squirrel cage fan and having multiple ultra quite computer fans in the duct work for the same air flow.

Another quicker approach would be use a motor speed controller. Maybe replace all the controlling logic with a ESP32 micro processor and sensors.

Here's an article on someone who performed such a modification with discreet electronics.

http://www.technology.niagarac.on.ca/people/mcsele/hobby/rv-fan-speed-controller/ (http://www.technology.niagarac.on.ca/people/mcsele/hobby/rv-fan-speed-controller/)

The latest buzz word out there is inverter driven compressor. Is there any advantage to trying to also modulate the compressor speed?

Any AC experts or others out there that want to weight in?
Title: Re: Coleman AC Woes
Post by: luvrbus on July 30, 2021, 10:59:37 AM
The way my Colemans are ducted you cannot hear them run.when they work and they are 2 motor setup 
Title: Re: Coleman AC Woes
Post by: windtrader on July 30, 2021, 12:09:50 PM
The inverter tech is used by most high-efficiency mini-split units which enable such impressive results; that is, low amp draw, both at startup and steady state operations.
Title: Re: Coleman AC Woes
Post by: Dave5Cs on July 30, 2021, 12:53:55 PM
 LOL Clifford asked if anyone knew how to tell him to fix his 2 Colemans that he already has, Not to rebuild his system, gessssss :)
Title: Re: Coleman AC Woes
Post by: luvrbus on July 30, 2021, 01:09:53 PM
Quote from: Dave5Cs on July 30, 2021, 12:53:55 PM
LOL Clifford asked if anyone knew how to tell him to fix his 2 Colemans that he already has, Not to rebuild his system, gessssss :)

Can you picture me Dave cutting holes in the floor ,doors and hanging the inside unit in the RV for mini splits.plus I am not waiting for hours for cool down, the 45,000 btu in the 3 Colemans will get you there in a hurry when it's 118 degrees   
Title: Re: Coleman AC Woes
Post by: thomasinnv on July 30, 2021, 01:37:46 PM
Clifford the only way to know for sure where the current draw is going is to use a clamp meter on each motor and the compressor and see what gives. If your control boxes are mounted inside the return plenum you can access them from underneath if you have access panels below the ac's. If not, or if they are miunted on the side of the unit, then it will require getting on the roof and pulling the covers.
Title: Re: Coleman AC Woes
Post by: luvrbus on July 30, 2021, 01:48:23 PM
Quote from: thomasinnv on July 30, 2021, 01:37:46 PM
Clifford the only way to know for sure where the current draw is going is to use a clamp meter on each motor and the compressor and see what gives. If your control boxes are mounted inside the return plenum you can access them from underneath if you have access panels below the ac's. If not, or if they are miunted on the side of the unit, then it will require getting on the roof and pulling the covers.


With my system Van told me how to check it through the SliverLeaf it worked one has blower fan drawing 12 amps,the other the compressor is spiking to 50 amps on startup and will drop to 23 amps in a few mintues.If I can find somewhere that has them in stock I am going to replace all 3 lol with my luck if I changed 2 the 3rd one would stop next week, thanks Derrick I was hoping you would answer since you are rv tech
Title: Re: Coleman AC Woes
Post by: Van on July 30, 2021, 02:24:19 PM
Lemme know when you find the new ones. :^
Title: Re: Coleman AC Woes
Post by: chessie4905 on July 30, 2021, 05:51:10 PM
you sure it doesnt need some capacitors replaced?
Title: Re: Coleman AC Woes
Post by: luvrbus on July 30, 2021, 05:56:36 PM
Quote from: chessie4905 on July 30, 2021, 05:51:10 PM
you sure it doesnt need some capacitors replaced?

Caps have all been replaced (9),the one with the spike the starter cap was fried well done ,the relay on the cap was melted so were the wires
Title: Re: Coleman AC Woes
Post by: Dave5Cs on July 30, 2021, 06:59:54 PM
Quote from: luvrbus on July 30, 2021, 01:09:53 PM


Can you picture me Dave cutting holes in the floor ,doors and hanging the inside unit in the RV for mini splits.plus I am not waiting for hours for cool down, the 45,000 btu in the 3 Colemans will get you there in a hurry when it's 118 degrees

No I can not lol. Maybe try another cap. I got on once new that turned out bad and I put the old one off another unit back and tested it and all was good. I got two I can sell you cheap that are only 14 years old,,,,, :^
Title: Re: Coleman AC Woes
Post by: luvrbus on July 30, 2021, 07:18:57 PM
Quote from: Dave5Cs on July 30, 2021, 06:59:54 PM
No I can not lol. Maybe try another cap. I got on once new that turned out bad and I put the old one off another unit back and tested it and all was good. I got two I can sell you cheap that are only 14 years old,,,,, :^

I did try another cap 2 in fact
Title: Re: Coleman AC Woes
Post by: chessie4905 on July 31, 2021, 06:33:10 AM
With new caps in place, read draw of compressor. Still bad, another unit. They do sell units that are more robust. Probably built like the old ones.
Funny you had two go bad at same time. Is the voltage to all three units staying the same when running? Problem with a leg of the 50 amp source?
Title: Re: Coleman AC Woes
Post by: luvrbus on July 31, 2021, 07:15:04 AM
Quote from: chessie4905 on July 31, 2021, 06:33:10 AM
With new caps in place, read draw of compressor. Still bad, another unit. They do sell units that are more robust. Probably built like the old ones.
Funny you had two go bad at same time. Is the voltage to all three units staying the same when running? Problem with a leg of the 50 amp source?

Voltage is good on both legs 121v ,I got another unit up and running now thanks to Van I pulled the blower motor and the thrust washer was gummed up and wore out, cleaned the coils and oiled the motor bought new washers at RV place and was surprised they had the washers for 3 bucks ea its running on a steady 13 amps this morning but it is cool here.The last one is going to be replaced it is low on Freon from a long screw rubbing a hole in a line lol you can tell some service tech has been in there on the unit changing the condensate pump  1/2 the screws were missing and taped up wires.John Coleman told these were the roughneck design with thicker tubing,mounts and coils 
Title: Re: Coleman AC Woes
Post by: dtcerrato on July 31, 2021, 08:52:36 AM
Sounds like them heat waves keeps ones on thier toes with A/C maintenance. That thrust washer issue you mentioned is a good find as it was eating 10A dragging the armature' s spin!
Florida has finally hit the mid to high 90s with similar humidity. Aug. is commonly our hottest month. We're enjoying the new ponderosa central HVAC upgrade & are noticing decrease in electric & cooler quicker cooling cycle. Stay cool...
Title: Re: Coleman AC Woes
Post by: Van on July 31, 2021, 09:08:22 AM
Hey Cliff, throw Chris up there an have him patch the lil' hole up. A son in law has to be good for at least some things ;D lol!
Title: Re: Coleman AC Woes
Post by: chessie4905 on July 31, 2021, 03:24:18 PM
I patched a hole in condenser a few years ago with an aluminum. solder stick with a propane torch. Wipe area clean and rub stick into tubing while applying torch. It worked fine. It is the stuff the vendors show attaching soda cans together. Ive always been skeptical of them, but it worked fine. Available at Harbor Freight also, but not wbere I saw the demonstation.
Title: Re: Coleman AC Woes
Post by: RichardEntrekin on August 01, 2021, 01:27:38 PM
Cliff,

Not trying to be an a$$. Do you have a clamp on AC amp meter? First diagnosis, is to find the wiring for the compressor and measure the amps during startup and run conditions. Without that info, it's guess.

One thing that will cause high amperage on the compressor is if the outside fan is not running. Without a fan removing heat from the high side, the compressor is under tremendous load, i.e. high amperage.
Title: Re: Coleman AC Woes
Post by: luvrbus on August 01, 2021, 03:21:28 PM
Quote from: RichardEntrekin on August 01, 2021, 01:27:38 PM
Cliff,

Not trying to be an a$$. Do you have a clamp on AC amp meter? First diagnosis, is to find the wiring for the compressor and measure the amps during startup and run conditions. Without that info, it's guess.

One thing that will cause high amperage on the compressor is if the outside fan is not running. Without a fan removing heat from the high side, the compressor is under tremendous load, i.e. high amperage.

Richard I do have a clamp on meter and the outside fan is running and spins easy.the one with the leak is the only unit not working now, the compressor will not start now 
Title: Re: Coleman AC Woes
Post by: RichardEntrekin on August 01, 2021, 04:32:41 PM
Great !

Sorry I was late to help, internet is not very good in the middle of nowhere Montana.
Title: Re: Coleman AC Woes
Post by: luvrbus on August 01, 2021, 09:30:21 PM
Quote from: RichardEntrekin on August 01, 2021, 04:32:41 PM
Great !

Sorry I was late to help, internet is not very good in the middle of nowhere Montana.

LOL I know the feeling internet is not great in Williams AZ either