Dometic AC needs capacitor

twalker H260 · Jan 11, 2022

Capacitor DUAL 30MFD/16MFD 370V R417A TURBO 16K 115V - Southern Marine Supply, Inc.

Capacitor DUAL 30MFD/16MFD 370V R417A TURBO 16K 115V

www.smsupplyinc.com

Project_Mayhem · Jan 14, 2022

Digikey seems to have every component under the sun

DeniseO30 · Jan 14, 2022

a capacitor be mounted almost anywhere that it will fit, just extend the wires. Do you know it's actually bad? (Shorted, open, leaking, swelling)
Ratings can be plus or minus 10% if memory serves,. This would also be a good time to install a hard start kit which is nothing more than a ceramic resistor although the larger ones have a start capacitor,

Ken13559 · Jan 17, 2022

My search tells me the uF (MFD, micro Farad) can be up to +20% and the voltage rating can be equal to stock or higher.

Ken Y

DeniseO30 · Jan 18, 2022

Ken13559 said:
My search tells me the uF (MFD, micro Farad) can be up to +20% and the voltage rating can be equal to stock or higher.

Ken Y

That reminds me back in the day when I had a thriving business we would pull the capacitors out of units coming out for replacementO often times when out on service calls they'd have some in the truck and say; "this one looks like it'll work"

there was a time when capacitors had pcbs in them.. yeah I'm that old lol

Tater · Jan 18, 2022

DeniseO30 said:
...... there was a time when capacitors had pcbs in them.. yeah I'm that old lol

My dad acquired a salvage pole transformer for a homemade welder. I played with the oil. I played with mercury too. I likely chewed on lead painted baby bed rails. I am that old too.

Ken13559 · Jan 18, 2022

I don't remember much and keeps forgetting where I ....... I'm that old too.

Crusty Ol Salt · Jan 18, 2022

Old?

My first set of orders in the Navy said "Go to Norfolk and wait for water"

Tater · Jan 18, 2022

Crusty,
I noticed you location. In October, my First Mate and I did a lighthouse tour from Maine to the Outer Banks. We stopped at Fort Monroe for Old Fort Comfort. While she got her photos, I watched the sailboats from the fishing pier. That trip was the inspiration to return to sailing after many years.

Crusty Ol Salt · Jan 18, 2022

Tater said:
Crusty,
I noticed you location. In October, my First Mate and I did a lighthouse tour from Maine to the Outer Banks. We stopped at Fort Monroe for Old Fort Comfort. While she got her photos, I watched the sailboats from the fishing pier. That trip was the inspiration to return to sailing after many years.

Funny thing is, I drive across the Hampton Roads Bridge Tunnel almost everyday. The view of the Old Point Comfort Marina and the sailboats cruising up and down the shipping channel and in the Chesapeake Bay reminded me daily that I promised myself that someday I would learn to sail. I love the views looking out from the Deadrise restaurant these days.

DeniseO30 · Feb 27, 2022

You might go on YouTube and look up how to "Ohm a compressor" but if it doesn't start, hums and clicks hums and clicks and still doesn't start, it's probably stuck (locked rotor) A hard start kit s
May start it what happens the liquid refrigerant forms droplets in the oil and keeps the Pistons from moving once it gets turned over there usually okay until whenever it happens again larger units have what is called a crankcase heater I keeps the compressor warm

JoeWhite · Mar 2, 2022

Yes, external relay can be used. If you are confident with the impedance of the coil and contact rating and voltage required to pull in the contacts you can wire it in. You have nothing to loose since you may have to replace the board in the worst case. Contact digi-key.com and contact their techs for suitable replacement. They may have the exact replacement.

DeniseO30 · Mar 2, 2022

Can't quite tell is the relay fried on the outside looks like it may be. I would not go out and buy circuit board until you're sure the compressor is good or bad, most technicians can test or even run the compressor without the circuit board why spend good money for bad, that amount of money is easily 25 to 30% that could go towards a new unit.

BigEasy · Mar 2, 2022

kbgunn said:
I have narrowed it down to the compressor relay on the control board. Compressor was getting 0v when the t-stat was calling for cooling. Water pump and fan run as expected. Replacement board is in the neighborhood of $300-400. Anyone ever replaced the relay on the circuit board? Or used an external relay soldered to the board?

Yes; however, my relay was on a separate board with jumpers to attach to main board. It was simple to replace and relatively inexpensive.
You might want to check out Flight Systems, Inc. They will trouble shoot for a nominal fee & provide an estimate. There is also a trouble shooting guide on their site.

www.flightsystems.com

Tater · Mar 2, 2022

DeniseO30 said:
Can't quite tell is the relay fried on the outside looks like it may be. I would not go out and buy circuit board until you're sure the compressor is good or bad, most technicians can test or even run the compressor without the circuit board why spend good money for bad, that amount of money is easily 25 to 30% that could go towards a new unit.

I am certified and at one time had a refrigeration contractors license. I have done the work in an institutional setting. I also have 40 years in electronics. The relay is likely just the tip of the burg. Relays don't just fail. The compressor is likely locked, a very common issue with small units. Denise has it right. Don't spend money unless you know for certain what the problem is.
I would replace the unit if it is 5 years old. If you can find a replacement that is not for a "BOAT" that can save money. At last resort a pro may be needed.

twalker H260 · Mar 2, 2022

Have you removed the board from its mount and had a look at the back side? Often when components go bad you will be able to see evidence of their failure on the back of the circuit board. - burn marks, cracked, melted or failed solder, missing component pins etc. In some cases the damage on the board from the failure will be such that the board itself can’t be reliably repaired.

All of that being said if it is a single relay that has failed they can usually be fairly easily replaced.

With board out You should be able to test the suspect relay with a 5v power source and check that the circuit closes properly.

DeniseO30 · Mar 2, 2022

Im 73 I was born in the contracting, most of all of it was in hvacr

Just keep in mind! most machines in the past 20 years even, are designed as throwaway technology that's why so many use a circuit board with all the controls on it.

Make sure the compressor is good! only three terminals start common run and the start capacitor with ceramic resistor. it's a very simple hook up once you know how, if you haven't thought of it you could probably pull the unit out of your boat and take it to somebody, its not much bigger or heavier than window unit.