RV.Net Open Roads Forum: Coleman Mach 8 AC - runs, no cold air

RV Blog

  |  

RV Sales

  |  

Campgrounds

  |  

RV Parks

  |  

RV Club

  |  

RV Buyers Guide

  |  

Roadside Assistance

  |  

Extended Service Plan

  |  

RV Travel Assistance

  |  

RV Credit Card

  |  

RV Loans

Open Roads Forum Already a member? Login here.   If not, Register Today!  |  Help

Newest  |  Active  |  Popular  |  RVing FAQ Forum Rules  |  Forum Posting Help and Support  |  Contact  

Search:   Advanced Search

Search only in Tech Issues

Open Roads Forum  >  Tech Issues

 > Coleman Mach 8 AC - runs, no cold air

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 2  
Next
Sponsored By:
pconroy328

Colorado

Senior Member

Joined: 01/30/2015

View Profile


Offline
Posted: 06/07/19 04:56pm Link  |  Quote  |  Print  |  Notify Moderator

2016 Coleman Mach 8 AC unit. No probs until today. Fans are running (squirrel and coil fans are running). Coils are clean, whole unit looks pretty clean under the cover.

I suspect the compressor ain't doing it's thing.
I've got an event to hit tomorrow so it'd be nice to see if there's a jury-rigging I can do.

I've got a good multimeter.
Can someone suggest some troubleshooting tips to see why it's blowing air but not cold air?

thanks!

DFord

Near St Louis, MO

Senior Member

Joined: 12/16/2001

View Profile



Good Sam RV Club Member

Offline
Posted: 06/07/19 08:05pm Link  |  Quote  |  Print  |  Notify Moderator

I think it's time to remove the cover on the roof to see if the compressor is HOT. If it is, it's getting power. If it's not even warm, test for power at the compressor terminals. This is LINE VOLTAGE SO BE CAREFUL! Under the cap on the compressor the wire terminals should be labeled C - S - R. That stands for Common, Start, and Run. You should be able to find 120v between C & R. If not, try measuring voltage between the compressor case or somewhere on the copper tubing and any of the terminals on the compressor when it should be running. If there's nothing there, the compressor contactor may not be pulling in. There will be a coil with smaller wires that you should be able to measure voltage at - probably 24v if the signal from the thermostat is reaching it. Or you could remove the cover from the thermostat and jumper R (red) to Y (yellow) to see if the compressor will start.


You might find some technical information on your AC at this page:
https://www.airxcel.com/coleman-mach/service-support/document-library

Coleman Thermostats Service Manual PDF file:
https://olivertraveltrailers.com/wp-cont........man_Mach/Thermostat/airxcel_19763761.pdf

Not knowing your AC model number, I can't give you a link to the documents there.


Don Ford
2004 Safari Trek 31SBD (F53/V10 20,500GVW)
'09 HHR 2LT Towed - BX1648 Baseplate
BlueOx Aventa II Towbar - ReadyBrake Inertia Brake System


pconroy328

Colorado

Senior Member

Joined: 01/30/2015

View Profile


Offline
Posted: 06/07/19 11:19pm Link  |  Quote  |  Print  |  Notify Moderator

Thanks - will pop back up there tomorrow! Compressor was NOT hot. Nothing was up there.

Hoping it's just a capacitor.
I'll pull the model number and schematic off the unit tomorrow.

Thanks again!

DFord

Near St Louis, MO

Senior Member

Joined: 12/16/2001

View Profile



Good Sam RV Club Member

Offline
Posted: 06/07/19 11:23pm Link  |  Quote  |  Print  |  Notify Moderator

If it was the capacitor, the compressor would be hot from trying to run without it.

dougrainer

Carrolton, Texas

Senior Member

Joined: 06/11/2007

View Profile


Offline
Posted: 06/08/19 06:19am Link  |  Quote  |  Print  |  Notify Moderator

If the compressor is running, then your Unit is shot and the upper unit needs replaced. Doug

twodownzero

NM

Senior Member

Joined: 06/07/2014

View Profile


Offline
Posted: 06/08/19 02:58pm Link  |  Quote  |  Print  |  Notify Moderator

dougrainer wrote:

If the compressor is running, then your Unit is shot and the upper unit needs replaced. Doug


I haven't seen an A/C compressor that ran in a unit that didn't produce any cold air yet.

DFord

Near St Louis, MO

Senior Member

Joined: 12/16/2001

View Profile



Good Sam RV Club Member

Offline
Posted: 06/08/19 04:31pm Link  |  Quote  |  Print  |  Notify Moderator

If the compressor was running and not circulating on refrigerant (not cooling) it would be way to hot to touch after just a few minutes.

dougrainer

Carrolton, Texas

Senior Member

Joined: 06/11/2007

View Profile


Offline
Posted: 06/09/19 06:58am Link  |  Quote  |  Print  |  Notify Moderator

twodownzero wrote:

dougrainer wrote:

If the compressor is running, then your Unit is shot and the upper unit needs replaced. Doug


I haven't seen an A/C compressor that ran in a unit that didn't produce any cold air yet.


Really, You base your comment on what expertise? I am basing my comment on 40 years and still working as a RV Tech. IF the compressor is Running, and NOT producing cold air, the Coolant is gone or the compressor valves are bad. Either way, you replace the upper AC unit. Doug

pconroy328

Colorado

Senior Member

Joined: 01/30/2015

View Profile


Offline
Posted: 06/09/19 08:46pm Link  |  Quote  |  Print  |  Notify Moderator

DFord wrote:

If it was the capacitor, the compressor would be hot from trying to run without it.


Thanks. Friday the compressor wasn't running. Yesterday, I musta bumped it enough that when I powered it on, the compressor started up. And it did get warm.

I went ahead and ordered the Start and Fan capacitors off Amazon and will replace them.

My fingers are crossed that's all it'll take.
Thanks for the help!

DFord

Near St Louis, MO

Senior Member

Joined: 12/16/2001

View Profile



Good Sam RV Club Member

Offline
Posted: 06/09/19 10:32pm Link  |  Quote  |  Print  |  Notify Moderator

Did you find any suspect quick connect terminals or wires burned where they connect? Bad capacitors are not known to heal themselves. Does the one in the metal can (the run capacitor) show any signs of bulging? That would be a sure sign it's gone bad. The start capacitor would usually show signs of damage if it were bad. The overheat very quickly if left in the circuit very long.

Reply to Topic  |  Subscribe  |  Print Topic  |  Post New Topic  | 
Page of 2  
Next

Open Roads Forum  >  Tech Issues

 > Coleman Mach 8 AC - runs, no cold air
Search:   Advanced Search

Search only in Tech Issues


New posts No new posts
Closed, new posts Closed, no new posts
Moved, new posts Moved, no new posts

Adjust text size:

© 2019 CWI, Inc. © 2019 Good Sam Enterprises, LLC. All Rights Reserved. | Terms of Use | PRIVACY POLICY | YOUR PRIVACY RIGHTS