Armstrong AC fan quits!

[bellastream]

I have a 1969 31 foot sovereign. When I turn on the AC it blows cold and strong. As it runs for a couple of minutes the fan seems to slow down then eventually just stops while the compressor just happily hums away. You need to wait for awhile to get the fan to come back on. Any suggestions?

[Bill M.]

On my 88 model with the original air conditioner the fan motor is outside under the shroud. I think you should get up there and check the bearings for lubrication and the wiring for corrosion. Mine failed because the hub for the outside fan corroded and failed and let the fan hit the housing. I ended up replacing the whole unit because of the fan and shaft condition even though the compressor was fine. You might have more incentive to just replace the fan motor or whatever you find that is causing the fan to stop.

[bellastream]

Originally Posted by Bill M.

On my 88 model with the original air conditioner the fan motor is outside under the shroud. I think you should get up there and check the bearings for lubrication and the wiring for corrosion. Mine failed because the hub for the outside fan corroded and failed and let the fan hit the housing. I ended up replacing the whole unit because of the fan and shaft condition even though the compressor was fine. You might have more incentive to just replace the fan motor or whatever you find that is causing the fan to stop.

Yeah the unit is in such good shape I can't just get rid of it I was thinking just replace the fan motor your right it's probably bearings or worn insulation on the armature. I am nervous to find a way on the roof. Any suggestions on how to get up there.

[overlander63]

On our Armstrong, the fiber washer at the base of the motor had worn down, allowing the rotor to drop slightly to the point it bound against the armature in the housing. My solution was to take the fan motor apart, and install a new washer. It worked for some time after.

[jbailey01]

I had the exact same problem with my first Airstream a 1972 30' with Armstrong A/C. After a summer of changing moters, condensers, I found the problem; a 5 cent wire nut that would not tighten. Replaced it, worked for years after. Very cold a ggod unit.

[bellastream]

Where was the wire nut located

[hprshtr]

I had the same problem on my 73 Argosy fan motor. It would run for a while and then stop. Turned out to be one of the bushings on the motor shaft was very worn. Replaced the bushing and all is well.

[alantbird]

Triflow bike chain lube at shaft/motor housing should give it the drink it needs. Or even a drop or two of high quality machine oil. Your in the N/W so I assume you dont know what cooler oil is but that the stuff. NOT 3way or WD40! If there's no side play it just really wants a sip of the good stuff!

[bellastream]

The weird thing is I take the air filter off and spin the fan by hand and it spins really well.

[bellastream]

Originally Posted by alantbird

Triflow bike chain lube at shaft/motor housing should give it the drink it needs. Or even a drop or two of high quality machine oil. Your in the N/W so I assume you dont know what cooler oil is but that the stuff. NOT 3way or WD40! If there's no side play it just really wants a sip of the good stuff!

I will try some marvel mystery oil that's what we use at work when we rebuild motors, but like I say it spins by hand really well.

[jbailey01]

The main electric feed. The compressor

Would continue to run after the fan stopped. Good luck

[bellastream]

Yes compressor runs after fan stops

[crestonrv]

it's a 40 year old window air conditioner that drafts downward .
maybe it's time to step up and buy a new 1 ?

[bellastream]

Originally Posted by crestonrv

it's a 40 year old window air conditioner that drafts downward .
maybe it's time to step up and buy a new 1 ?

These "40 year old window AC units are built tough and parts are available today to repair them. They are not throw away junk like they have today. Anyhow I fixed it seems I had the thermostat wired wrong now blows ice cold continuously.

[Aage]

Originally Posted by bellastream

These "40 year old window AC units are built tough and parts are available today to repair them. They are not throw away junk like they have today. Anyhow I fixed it seems I had the thermostat wired wrong now blows ice cold continuously.

There is a sticky about this same subject here that is an interesting read. Member Jason Pratt completely rebuilt his 40-year-old Armstrong, and even upped it's output significantly while adding the heatpump feature!

If all the work he did would have reduced the noise the Armstrong makes, it would have been tempting to consider doing, but apparently such is not the case.

[Fixintime]

I had the motor windings on the Armstrong A/C unit fail on my '76 Argosy. Smelled burning plastic and the motor could be spun but would not run. The compressor would start just fine. Replaced the motor with a Dayton 5WJC4 from Grainger for $103 plus tax. Had to cut the shafts and not use one of the speeds of the motor, took some wiggling to get it all in there and buttoned back up, but been working fine for the past 2 weeks.

Checked and replaced the compressor capacitors while in there.

Word of warning, this is a four speed motor and my system was only for 3 speeds. Just leave one of the speed wires unconnected and it works fine.

[VetteGuy]

Does this look like your unit? If so I can tell you that I had the same issue.. let me know

[Fixintime]

VetteGuy - No, my unit is from a '76 Argosy. I will post a picture of the internals when I get back on the roof, but mine is a horizontal orientation with a dual shafted motor. One end runs the internal blower and the other end is the fan for the condenser.

With a little searching, it should be possible to find a motor that will work for your unit. My 2-fold reason for fixing the old one - 1) I do not believe the newer units are built like the old ones (this one lasted 40 years), and 2) It was cheaper than replacing it.

[VetteGuy]

About compressor on the internet for $300 the part number is on a compressor not the tag by the AC unit mine was embossing to the unit on a welded tag attached to the compressor I cross-referenced and bought a new one a random guy from Craigslist put it in for 300 bucks