Diagnosing Duo Therm AC

[IndyAnne]

Hello, Forum friends,

I'm learning how to use my MobileMe to publish photos. I hope you can see the photos from this link:

MobileMe Gallery

I am trying to figure out what to do about this air conditioner. I bought it on eBay in 2007, had it installed here in Indy, enjoyed it a couple of seasons until a trip in late June 09, Grand Rapids, a hot blast for a couple of days. I turned it on, and discovered it would not cycle into cooling. The compressor would hum for a second, but quit. After turning it off, it would then make a sound like turning a rain stick upside down, or running cold water into a pan of burning hot oil.

Someone suggested a low voltage situation at the campground, but other RVs nearby were running AC just fine. The owner of the campground came to do a voltage check, said it was fine. I tried all kinds of things: ran it on a separate extension cord on the campground's power supply, tried a 15 amp cord and a 20 amp cord -- same result. I checked fuses.

I did smell an acrid melting electrical insulation smell and checked the Airstream fuse box. The breaker was blistered, and very hot to touch (why didn't it trip? worrisome). I let it cool down, unplugged the AC, and went out and got a plain ol' table fan (no Fantastic vent yet), suffered through the heat til the weather changed.

I've been going around with the AC on the roof ever since, using the fan, but not working on it until now. I'm an untenured higher education economy casualty, under-employed, and spending only on things I know how to do, waiting for a chance to afford the labor cost in removing the AC to fix it or replace it. I don't like having things that I can't reach to work on myself. And, I don't like throwing good money after bad.

I've had a Fantastic Vent in the garage for a year, waiting to remove the AC. Now is the time.

Where did the bad money go? The AC was not wired properly. I made a big mistake and trusted installation to the wrong people. They ran the AC on the same circuit with the other 120v appliances, not on the factory wiring, but I was not paying close attention -- until I changed the breaker and sorted everything out. "Trust me -- it's fine, they said." I learned my lesson. I would rather p*&^ off the RV techs than burn up in a fire. No one likes to work on a vintage Airstream, I realize that. That's why I would rather have appliances and stuff I can deal with all by myself.

Last weekend I had the AC removed at a different business, had them put it in the bed of my truck. Again, I don't like having the AC on the roof because I can't reach it well enough to work on it, I don't (yet) have a nice gantry and block and tackle set up, and the AC is too heavy for me.

I'm going to look for other options for AC. It gets too hot and humid in Indiana to not have one. We are in a family habit of gathering at Patoka Lake on what turns out each year to be the hottest week on record. Change weeks? Inlaws and outlaws have a time share near the lake (French Lick); have you ever tried to change time share weeks? sheesh -- it's easier to just get an air conditioner.

I digress. Where was I?

I read on the forums here that the problem could be the start motor and capacitor. I felt encouraged. Parts could be purchased at Grainger's; there's a Grainger's in Speedway.

This morning I took the shroud off, opened the compartment with the start motor. I found no blistering as suggested in the thread I was referring to. Everything is all shiny.

All shiny, except for a film of yellow oily residue that seems to have dripped into the compartment with the electrical start parts. This yellow oil is spread over the entire corner (curb side right front), including inside the left side of the little electrical compartment, and seeped down into the pan. It has discolored the aluminum canister beside the start capacitor within the little electrical compartment.

I am not sure now whether or not I should go to Grainger's to see if they have the parts suggested by the other thread, or if this yellow oil is refrigerant and I am SOL.

If it is refrigerant, is it worth it to have orifices brazed onto the refrigerant line and try to salvage the machine? Anybody want to try? I'll sell it to you cheap! Before this, I used it maybe three times, and it's only been on the trailer for three years.

Any suggestions will be welcome.

Thanks,
Anne

[Inland RV Center, In]

Originally Posted by IndyAnne

Hello, Forum friends,

I'm learning how to use my MobileMe to publish photos. I hope you can see the photos from this link:

MobileMe Gallery

I am trying to figure out what to do about this air conditioner. I bought it on eBay in 2007, had it installed here in Indy, enjoyed it a couple of seasons until a trip in late June 09, Grand Rapids, a hot blast for a couple of days. I turned it on, and discovered it would not cycle into cooling. The compressor would hum for a second, but quit. After turning it off, it would then make a sound like turning a rain stick upside down, or running cold water into a pan of burning hot oil.

Someone suggested a low voltage situation at the campground, but other RVs nearby were running AC just fine. The owner of the campground came to do a voltage check, said it was fine. I tried all kinds of things: ran it on a separate extension cord on the campground's power supply, tried a 15 amp cord and a 20 amp cord -- same result. I checked fuses.

I did smell an acrid melting electrical insulation smell and checked the Airstream fuse box. The breaker was blistered, and very hot to touch (why didn't it trip? worrisome). I let it cool down, unplugged the AC, and went out and got a plain ol' table fan (no Fantastic vent yet), suffered through the heat til the weather changed.

I've been going around with the AC on the roof ever since, using the fan, but not working on it until now. I'm an untenured higher education economy casualty, under-employed, and spending only on things I know how to do, waiting for a chance to afford the labor cost in removing the AC to fix it or replace it. I don't like having things that I can't reach to work on myself. And, I don't like throwing good money after bad.

I've had a Fantastic Vent in the garage for a year, waiting to remove the AC. Now is the time.

Where did the bad money go? The AC was not wired properly. I made a big mistake and trusted installation to the wrong people. They ran the AC on the same circuit with the other 120v appliances, not on the factory wiring, but I was not paying close attention -- until I changed the breaker and sorted everything out. "Trust me -- it's fine, they said." I learned my lesson. I would rather p*&^ off the RV techs than burn up in a fire. No one likes to work on a vintage Airstream, I realize that. That's why I would rather have appliances and stuff I can deal with all by myself.

Last weekend I had the AC removed at a different business, had them put it in the bed of my truck. Again, I don't like having the AC on the roof because I can't reach it well enough to work on it, I don't (yet) have a nice gantry and block and tackle set up, and the AC is too heavy for me.

I'm going to look for other options for AC. It gets too hot and humid in Indiana to not have one. We are in a family habit of gathering at Patoka Lake on what turns out each year to be the hottest week on record. Change weeks? Inlaws and outlaws have a time share near the lake (French Lick); have you ever tried to change time share weeks? sheesh -- it's easier to just get an air conditioner.

I digress. Where was I?

I read on the forums here that the problem could be the start motor and capacitor. I felt encouraged. Parts could be purchased at Grainger's; there's a Grainger's in Speedway.

This morning I took the shroud off, opened the compartment with the start motor. I found no blistering as suggested in the thread I was referring to. Everything is all shiny.

All shiny, except for a film of yellow oily residue that seems to have dripped into the compartment with the electrical start parts. This yellow oil is spread over the entire corner (curb side right front), including inside the left side of the little electrical compartment, and seeped down into the pan. It has discolored the aluminum canister beside the start capacitor within the little electrical compartment.

I am not sure now whether or not I should go to Grainger's to see if they have the parts suggested by the other thread, or if this yellow oil is refrigerant and I am SOL.

If it is refrigerant, is it worth it to have orifices brazed onto the refrigerant line and try to salvage the machine? Anybody want to try? I'll sell it to you cheap! Before this, I used it maybe three times, and it's only been on the trailer for three years.

Any suggestions will be welcome.

Thanks,
Anne

Anne.

That oil is probably from one of the capacitors. That would also explain the no start.

Andy

[Diesel1]

ditto...what Andy said. Adios,John

[IndyAnne]

... I had no idea! So, I could go to Graingers with these parts and maybe they will have them, and I can get the AC going.

I'll get back to you on the result.

Thanks, Andy and John!

[IndyAnne]

As update photos show, I removed the shroud covering the condenser and discovered a broken copper line. No easy fix after all. Now I can decide how to proceed -- sell as-is, repair, contact Duo Therm and see what they might have to say.

MobileMe Gallery

I'm leaning toward selling as-is. I can weld, but I'm not skilled in brazing. This looks like it might be a vulnerable location. And, I am not skilled in recharging refrigerant.

Another thought -- I've been thinking of a road trip up to the Elkhart area to get some interior decorating supplies and maybe some awning fabric. I think Duo Therm is also in the area.

[Inland RV Center, In]

Originally Posted by IndyAnne

As update photos show, I removed the shroud covering the condenser and discovered a broken copper line. No easy fix after all. Now I can decide how to proceed -- sell as-is, repair, contact Duo Therm and see what they might have to say.

MobileMe Gallery

I'm leaning toward selling as-is. I can weld, but I'm not skilled in brazing. This looks like it might be a vulnerable location. And, I am not skilled in recharging refrigerant.

Another thought -- I've been thinking of a road trip up to the Elkhart area to get some interior decorating supplies and maybe some awning fabric. I think Duo Therm is also in the area.

Anne.

To braze that crack takes less than a minute. But setting up the torch etc, takes more time than the fix.

Now, for the cause of that crack, in that tough area?

Unbalanced running gear and/or worn out rubber rods in the axle.

Andy

[IndyAnne]

I was just thinking the same thing.

The condition of the running gear, the copper gets work-hardened by repeated bending, cracks open, refrigerant escapes, no more cool in August.

It's a hard life on the roof of an Airstream that needs new axles & shocks.

Originally Posted by Inland RV Center, In

Anne.

To braze that crack takes less than a minute. But setting up the torch etc, takes more time than the fix.

Now, for the cause of that crack, in that tough area?

Unbalanced running gear and/or worn out rubber rods in the axle.

Andy

[IndyAnne]

Quick note to close this topic: I sold the air conditioner. Someone had a brazing set-up in the family.

Anne

Originally Posted by IndyAnne

I was just thinking the same thing.

The condition of the running gear, the copper gets work-hardened by repeated bending, cracks open, refrigerant escapes, no more cool in August.

It's a hard life on the roof of an Airstream that needs new axles & shocks.

[Aviator]

If you need axles, the Henschens are back in production and being made in Elkhart. Andy set me with an order and I picked them up at the factory which saved the shipping costs. Shipping is less to Indy than Atlanta, but still......

[IndyAnne]

Originally Posted by Aviator

If you need axles, the Henschens are back in production and being made in Elkhart. Andy set me with an order and I picked them up at the factory which saved the shipping costs. Shipping is less to Indy than Atlanta, but still......

Thank you for the tip! Axles are at the top of my list.