Reply
 
Thread Tools Search this Thread Display Modes
 
Old 06-02-2008, 07:48 PM   #1
2 Rivet Member
 
Gael79's Avatar
 
1970 31' Sovereign
Lombard , Illinois
Join Date: Apr 2008
Posts: 93
Armstrong A/C Question

We just got our Airstream in April, and I have never ran the A/C before. Could someone please tell me if this is normal? The Trailer is a 1970 Sovereign, and the A/C unit is an Armstrong TR21-12.

I was out camping with the family this past weekend, and was in a camping spot that was about 50 feet from the electrical hook-up. I did not have enough of the Airstream's Black 30 Amp power cable to make it to the hook up. I did have a stout 20 Amp Extension cord so I made due, until Sunday afternoon ( without trying to run the A/C).

Finally, Sunday afternoon after I pulled out of our site, I snuck into another site, and tried to run our A/C, directly off of the Airstream's 30A power cord.

It got about 5 minutes of "stick time" with the A/C unit. The outside air temp was 84 F. this inside temp was close to that, because all the windows and vents had been closed for 1/2 hour plus. I cranked the thermostat to it's lowest setting, Switched from OFF to COOL, and selected high.

The fan came on loud and strong. My wife said a bunch of leaves and crap blew out the top like a salad shooter. Inside, unaware of the display outside, I believe the fan ran steady and strong, but it sounded like the compressor was pulsing every 15 seconds or so. I question this and would like to know if this is normal. We have a Trane "Pulse" furnace in our home, and this is the same sound it makes under normal heating conditions.

I believe the exhaust air temp inside dropped about 3 degrees, (I have one of those IR guns that reads remote temps, brought it with to verify refrig/freezer temp on the old Dometic) but like I said, only ran the A/C for about 5 minutes.

Any comments would be grately appreciated. Sure would like to know if this thing is working O.K. I am more concerned about the pulsing compressor sound. Even if it cools, and this is not normal, I would not want to take a chance on burning up the compressor.

Could someone who has had experience with this unit please chime in with their comments?

Thank you!!!
__________________

__________________
Scott

I have a picture of my Airstream in my wallet, and I'm sitting on it...

...If that's not love, I don't know what is!
Gael79 is offline   Reply With Quote
Old 06-03-2008, 04:30 PM   #2
3 Rivet Member
 
racoco's Avatar
 
1976 31' Sovereign
2007 19' Bambi
Midland , Texas
Join Date: Feb 2004
Posts: 124
I don't think this sounds normal. Every 15 seconds or so makes me think there may be a problem with the thermostat or possibly the wiring. Our Armstrong runs strong and cold (and loud) until the thermostat pulls it back.

By the way, you can pick up a 30Amp extension cord at Camping World. Don't need it often, but...

Good luck.
__________________

__________________
racoco is offline   Reply With Quote
Old 06-03-2008, 04:37 PM   #3
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
Quote:
Originally Posted by Gael79
We just got our Airstream in April, and I have never ran the A/C before. Could someone please tell me if this is normal? The Trailer is a 1970 Sovereign, and the A/C unit is an Armstrong TR21-12.

I was out camping with the family this past weekend, and was in a camping spot that was about 50 feet from the electrical hook-up. I did not have enough of the Airstream's Black 30 Amp power cable to make it to the hook up. I did have a stout 20 Amp Extension cord so I made due, until Sunday afternoon ( without trying to run the A/C).

Finally, Sunday afternoon after I pulled out of our site, I snuck into another site, and tried to run our A/C, directly off of the Airstream's 30A power cord.

It got about 5 minutes of "stick time" with the A/C unit. The outside air temp was 84 F. this inside temp was close to that, because all the windows and vents had been closed for 1/2 hour plus. I cranked the thermostat to it's lowest setting, Switched from OFF to COOL, and selected high.

The fan came on loud and strong. My wife said a bunch of leaves and crap blew out the top like a salad shooter. Inside, unaware of the display outside, I believe the fan ran steady and strong, but it sounded like the compressor was pulsing every 15 seconds or so. I question this and would like to know if this is normal. We have a Trane "Pulse" furnace in our home, and this is the same sound it makes under normal heating conditions.

I believe the exhaust air temp inside dropped about 3 degrees, (I have one of those IR guns that reads remote temps, brought it with to verify refrig/freezer temp on the old Dometic) but like I said, only ran the A/C for about 5 minutes.

Any comments would be grately appreciated. Sure would like to know if this thing is working O.K. I am more concerned about the pulsing compressor sound. Even if it cools, and this is not normal, I would not want to take a chance on burning up the compressor.

Could someone who has had experience with this unit please chime in with their comments?

Thank you!!!
You must not use an small extension cord.

You should be using a # 8 cord, or better yet, a # 6 cord.

If you continue to use a small cord, you will ruin the compressor.

The cutting off every few minutes is a warning.

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 06-03-2008, 04:57 PM   #4
4 Rivet Member
 
1975 27' Overlander
High River , Alberta
Join Date: Aug 2006
Posts: 393
Quote:
Originally Posted by Inland RV Center, In
You must not use an small extension cord.

You should be using a # 8 cord, or better yet, a # 6 cord.

If you continue to use a small cord, you will ruin the compressor.

The cutting off every few minutes is a warning.

Andy
Actually, he said he was using a 20 amp extension cord for the weekend, and avoided using the A/C. He moved temporarily to another site to use a 30 amp plug without the extension cord to test the A/C.

The "pulsing" of the compressor every 15 seconds or so may signal a low refrigerant charge. You'll need to use it some more to know. (There's probably more debris under the cover; you would be well advised to remove the cover and clean things out with a garden hose first so that the condensor fins can properly transfer heat.)

When you test it again, you may find that it cools, but stops cooling after a while. A low refrigerant charge will lead to icing of the evaporator. Using a low fan speed can aggravate icing as well. Turning up the thermostat and letting the fan run for a while gets rid of the ice, but then the cycle gets repeated.
__________________
AlbertF is offline   Reply With Quote
Old 06-04-2008, 12:00 PM   #5
2 Rivet Member
 
Gael79's Avatar
 
1970 31' Sovereign
Lombard , Illinois
Join Date: Apr 2008
Posts: 93
Thanks to All...

Thank you one and all for your input. Yeah, I'll have to run it longer, and will remove the shroud and clean well before the next testing. I am considering a 30 Amp outlet near my garage, but that is in the future.

I have a co-worker that thinks the cycling compressor means that the freon is low. I don't know, but if that is the final fix, I'll let everyone know.

Does anyone happen to know if R-12 or R22 was used in this unit???

Thank again,
__________________
Scott

I have a picture of my Airstream in my wallet, and I'm sitting on it...

...If that's not love, I don't know what is!
Gael79 is offline   Reply With Quote
Old 06-04-2008, 12:12 PM   #6
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
Quote:
Originally Posted by Gael79 View Post
Thank you one and all for your input. Yeah, I'll have to run it longer, and will remove the shroud and clean well before the next testing. I am considering a 30 Amp outlet near my garage, but that is in the future.

I have a co-worker that thinks the cycling compressor means that the freon is low. I don't know, but if that is the final fix, I'll let everyone know.

Does anyone happen to know if R-12 or R22 was used in this unit???

Thank again,
R-12 is never used in an RV roof AC.

R-22 is always used.

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 06-04-2008, 12:39 PM   #7
Rivet Master
 
1984 31' Excella
Norfolk , Virginia
Join Date: Jan 2005
Posts: 667
Images: 11
A/c

Gael
First determine if the compressor is running or humming.
If it humms for a moment then a click is heard then the humming stops don't try it any more.
Locate a service person before you try to run it again or you could burn up the compressor.
What is happening is the compressor is failing to start and the over current circuit breaker (internal) is tripping out (automatically opening the circuit).
Find an AC service person. A good one you trust.
This could be as simple as a bad run capacitor ($8.00 to $20.00 for the part) or as serious as a stuck compressor (replace the AC).
If the compressor is actually starting the small tubing comming out ot the compressor will start to get really hot.
I kinda doubt that the compressor is actually running. Given the age the run cap is a very good culprit.
The blower motor probally also also has a run cap.
The reason for the run cap is far too long to go into here.
Beginner
__________________
Beginner is offline   Reply With Quote
Old 07-08-2008, 03:41 PM   #8
1 Rivet Member
 
1972 31' Sovereign
Loogootee , Indiana
Join Date: Jul 2008
Posts: 11
OK, I have a related problem. I just bought a 71 Soveriegn out of a weed field where it has sat unopened since 1983. We're still cleaning the mouse droppings and similar debris, but mostly things appear well preserved. On the AC, which is also an Armstrong, I turned it on to see if it would do anything at all and to my surprise it actually came on and started to blow air cooler than the ambient air. Good sign!. But after about a minute it sounded like the compressor kicked off and the fan continued to run. I shut it down and scratched my head for a while, then tried it again. And it did the same thing again. Then quit doing anything at all; like no power to the unit. Maybe a breaker, but I have not found those yet, and all the other 110 VAC systenms seem to work OK. Is the 71 Armstrong worth fixing or should I just replace it and move on?
__________________
Maxom is offline   Reply With Quote
Old 07-08-2008, 03:47 PM   #9
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
Quote:
Originally Posted by Maxom View Post
OK, I have a related problem. I just bought a 71 Soveriegn out of a weed field where it has sat unopened since 1983. We're still cleaning the mouse droppings and similar debris, but mostly things appear well preserved. On the AC, which is also an Armstrong, I turned it on to see if it would do anything at all and to my surprise it actually came on and started to blow air cooler than the ambient air. Good sign!. But after about a minute it sounded like the compressor kicked off and the fan continued to run. I shut it down and scratched my head for a while, then tried it again. And it did the same thing again. Then quit doing anything at all; like no power to the unit. Maybe a breaker, but I have not found those yet, and all the other 110 VAC systenms seem to work OK. Is the 71 Armstrong worth fixing or should I just replace it and move on?
Your describing the behavior of an AC that is reacting to an extension cord, that is way to small.

Try plugging the trailer into a "known" AC outlet that has at least a 20 amp rating.

Small extension cords are a death sentence for RV AC's.

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 07-08-2008, 04:28 PM   #10
1 Rivet Member
 
deep river , Connecticut
Join Date: May 2008
Posts: 18
I have a 71 overlander with an armstrong and today an ac guy came over to recharge the unit and the is only a lowside valve and not a highside valve. any ideas on where it is??? is it inside??
__________________
durbin is offline   Reply With Quote
Old 07-08-2008, 04:51 PM   #11
Rivet Master
Airstream Dealer
 
Inland RV Center, In's Avatar
 
Corona , California
Join Date: Feb 2002
Posts: 16,499
Images: 1
Quote:
Originally Posted by durbin View Post
I have a 71 overlander with an armstrong and today an ac guy came over to recharge the unit and the is only a lowside valve and not a highside valve. any ideas on where it is??? is it inside??
Don't need one.

But, if you wish, you can install a line-a-tap in the high pressure side, which is the smaller diameter tubing.

Unless the AC has tons of miles, the compressor will increase the low pressure by a factor of 4.

Therefore if the low side says 75 psi, then the high side will say 300 psi.

Most AC units are filled from the low side, using the ambient exterior temperature as a guide, which will tell the AC guy, what pressure to use on the low side.

Make sure he understands that your AC uses R-22 freon.

Andy
__________________
Inland RV Center, In is offline   Reply With Quote
Old 07-08-2008, 06:40 PM   #12
Rivet Master
 
TomW's Avatar
 
1967 26' Overlander
Huntsville , Alabama
Join Date: Dec 2003
Posts: 2,918
Images: 2
Caution is warranted

Quote:
Originally Posted by Inland RV Center, In View Post
Don't need one.

But, if you wish, you can install a line-a-tap in the high pressure side, which is the smaller diameter tubing. ....
Andy is correct in what he says. No high-pressure tap is necessary.

I advise against installing a high-pressure tap UNLESS the tap is silver-soldered in. A self-piercing saddle tap will leak. But since it does not involve evacuating & recharging the system like a properly installed tap does, it is much faster to install. And it will leak.

A self piercing, saddle tap is not a good idea.

Tom
p.s. Did I mention a self piercing, saddle tap will leak?
TomW is offline   Reply With Quote
Old 07-08-2008, 06:44 PM   #13
Rivet Master
 
1984 31' Excella
Norfolk , Virginia
Join Date: Jan 2005
Posts: 667
Images: 11
Ac

If there is no high side tap, dont install a saddle clamp on type as they do leak.
You can add gas into the los side until the compressor's run current (requires an AC clamp on amp meter) is atained.

Beginner
__________________
Beginner is offline   Reply With Quote
Old 07-09-2008, 06:24 AM   #14
1 Rivet Member
 
1972 31' Sovereign
Loogootee , Indiana
Join Date: Jul 2008
Posts: 11
Quote:
Originally Posted by Inland RV Center, In View Post
Your describing the behavior of an AC that is reacting to an extension cord, that is way to small.

Try plugging the trailer into a "known" AC outlet that has at least a 20 amp rating.

Small extension cords are a death sentence for RV AC's.

Andy
I actually didn't plug into anything but a proper 30 amp supply, but I am sure it was used on an improper supply in the past. I know because when I found the electric cable in the rear bumper it was still connected to a 20 amp cord with an adapter, and the ends of the small cord and the adapter were badly burned from over heating. So, you are correct that this unit has been abused in that way.

Since it did come on and start to cool, and then quit, should we assume it is ruined?

By the way Andy, thanks for your help. I am a park manager in my day job, and we find those small cords and adapters to be the most common misunderstood trouble makers in our campgrounds. They not only kill AC units, but they also burn up campground electrical systems, increase electric costs and cause a lot of outages for the culprits' neighboring campers. You'd be surprised how many otherwise intelligent people will cobble up a Y device to plug a 50 AMP RV into both the 30 and the 20 AMP receptacles, thinking that gives them 50 AMPS. We also see a lot of 14 guage, 100 foot long cheap cords being plugged into the supply and then an adapter out at the end to plug in the 30 or even 50 AMP camper cord. Those folks always call complaigning about power problems. Go Figure.
__________________

__________________
Maxom is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Armstrong A/C Question Sundance Furnaces, Heaters, Fireplaces & Air Conditioning 6 04-14-2007 08:32 PM
armstrong a/c mike beech Furnaces, Heaters, Fireplaces & Air Conditioning 16 01-06-2007 06:31 PM
Armstrong AC Filter DPeakMD Furnaces, Heaters, Fireplaces & Air Conditioning 3 07-14-2005 01:43 PM
Original Armstrong furnace Co Air conditioner question. Mark K Airstream Motorhome Forums 3 09-20-2003 10:04 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 11:02 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.