A/C Capacitor Duo Therm

[Cyanne]

I went up on the roof of the RV and took off the AC cover. What’s up there says Duo Therm model # 630035.322 serial # 45030182. I’m trying to find capacitors (I need 2) to go with the model/serial numbers but I’m coming up blank. Anybody have suggestions. I know I just can’t purchase anything. Thanks everyone.

[Jim_HiTek]

Usually if you record the Value in MF or mf (microfarads) or even uF, and the voltage, you can use any generic cap with the same or higher ratings (within reason). Plug those listings off the old caps into google and it'll likely give you several choices of that exact cap.

Get those values, post them here, and we can help too. For a '05, getting a sub rather then exact replacement would be pretty typical...though the replacement would probably have the same ratings for voltage and mf's.

[Old-Biscuit]

Parts List with exploded view and part numbers
https://www.nwtfc.com/wp-content/upl...s_listed7e.pdf

Part 43 --- fan start/run
Part 46 --- start capacitor

[Jim_HiTek]

Here's one of them: Dual 20 UF & 10 UF, 370 Vac motor capacitor

And here's the Start capacitor: Start Cap

[Old-Biscuit]

Originally Posted by Jim_HiTek

Here's one of them: Dual 20 UF & 10 UF, 370 Vac motor capacitor

And here's the Start capacitor: Start Cap

Hummmmmmmmmmmm
Those match the numbers in the Parts List I posted

[Jim_HiTek]

Originally Posted by Old-Biscuit

Hummmmmmmmmmmm
Those match the numbers in the Parts List I posted

They sure do! It's the magic of google. Woooooooo [weird music]...

[Bsipe01]

Find the ratings on the OEM capacitors. You can visit a local HVAC/R supply house and pick up replacements. You don't need OEM parts, a capacitor is a capacitor. Match the uf rating, the voltage can be higher than the original, but not lower. They're not terribly expensive, and you should have no trouble matching them. The shape may be a problem, but the shape is irrelevant as long as the replacement can be mounted securely. You can also replace a dual capacitor with two individual caps as long as the ratings match. Any cap that's bulged, weeping, or stinks like burnt wiring is candidate for replacement. If in doubt and you don't have the meter to test it, replace it. Cheap insurance. A DMM with a capacitor test function is a big help. Remove the wiring from one terminal, Short the leads before testing.Test, short, swap leads, test again. Readings should be the same. Replace if out by >10%.

[Ray,IN]

FIRST!f unplug from electricity, then discharge all capacitors by touching both contacts together with a screwdriver. Otherwise you may get a shocking surprise.

[Cyanne]

We’ve replaced the “silver box” inside the unit in the rear bedroom; replaced the comfort control duo therm thermostat. The capacitors are good. I’ve been told it’s the solenoid reversing valve that’s causing the problem. Can this item be replaced? Has anyone replaced theirs? Is there a video that can show me how? I’ve looked on YouTube and can’t find one. Or do I have to replace the entire roof air conditioner? I’ve seen those prices whoo-weee. Please help. Thank you

[Old-Biscuit]

In Link I posted it shows 2 items for reversing valve
The Solenoid...which is easy to replace
Dometic 3105504.009

Reversing valve is whole different thing.....it comes with all the lines attached and would require removal of old valve/lines, soldering in new valve lines and recharging system'
Gonna rack up $$$$ might be best to get NEW A/C Unit with heat pump
Nothing is cost effective!

[Jim_HiTek]

You have a 20 yo RV. Those capacitors can measure good and still be bad, due to excess leakage, film and electrolyte breakdown under load, and the fact that they are 20 years old.

How did you decide they are good? They are the most common failure item in a roof top AC. Substitution is the best method of testing them. Just curious.

As Old-Biscuit says, the shuttle solenoid is easy to replace, the shuttle valve is a whole nuther level.

[Roy1]

You don’t say what is the problem? Reversing valves rarely go bad I only changed a couple in 30 years . With the unit running energize the solenoid then de energize it it should go from heat to cool or vice versa. To check if the valve is sticking feel the pipe going to the compressor suction and feel the pipe coming from the cooling coil both should be cool at approximately the same temperature . There is a big difference suspecting bad capacitors or a reversing valve ? Does the unit operate or trip the breaker is the fan or compressor operating etc?

[Cyanne]

Roy1
When I turn on the air conditioning it blows cold for a few seconds then I hear this “click swoosh” sound and the air blows hot like I turned on the heat. It only happens to the air in the rear. The front air works just fine

[Cyanne]

Took it to an HVAC place they said it was fine but they don’t change out stuff like that. They only replace. The price they quoted was very high. I saw an air conditioner to replace on Amazon and it was nowhere near what they quoted me. If I have to replace I’ll get it from Amazon and it’ll be a DIY project