Installing a new capacitor in my Coleman A/C

whs9841 wrote:
Chris, a few questions about your response:

1. If I piggyback the SPP6 on the larger capacitor, do I just connect the wires from the SPP6 to the two different posts on the larger capacitor?

Yes- exactly.

2. Is there a way to wire the SPP6 as a compressor start capacitor for this a/c?

That's what it will be doing- added to the compressor run capacitor.

3. How would the SPP6E benefit me more in this scenario? How would it be hooked up to the A/C with the existing capacitors?

The difference between the E sries and standard series is that the E series uses a speed sensing relay to take the start capacitor out of the circuit, the standard uses a PTCR, which simply gets hot and stops conducting, taking the capacitor out of the circuit. For normal use this works well, and is cheap. However, when running on a generator, the generator will usually bog down for a second, and because the PTCR is basically time based, it takes the start capacitor out of the circuit before the compressor is running at speed. The E series keeps it in the circuit until the compressor is running at ~75% speed.
Supco doesn't recommend the E series because if you cycle the compressor off and right back on, the capacitor is in the circuit for too long a time, because the compressor cannot start against the high pressure. This is harder on the compressor.

If you don't run on a generator, the E gives no advantage, but it can make the difference between starting and not when running on a marginal genset.

You want a single start kit- more is not better.

FWIW, there are actually better kits out there, though they are a bit more complicated to install. They use 3 wires and a true potential relay. Dometic makes a factory start kit specifically for the Penguin and Onan 2.8.

Your model RVP ALREADY has a hard start capacitor for the compressor. It came from RVP with OEM Hard Start capacitor.
The 2ndnumber after the LETTER in the model number tells you that.

If 5 or 6, NO hard start cap
If 7-8-9, it HAS the hard start capacitor.
8335D8764 The "7" tells that you have the OEM hard Start Capacitor.

Doug

I didn't see j-d's response before my previous message. Now I'm kicking myself...I originally ordered the SPP6E, but saw numerous posts stating the 6E is not recommended for RV a/c usage, and the SPP6 is what Supco recommends.

Since the SPP6 capacitor should be delivered later today or tomorrow, would I get any extra benefit to piggyback the SPP6 capacitor to the compressor run capacitor, and then when I get the SPP6E I can also add it to the compressor run capacitor and it will act as a start relay/start cap? That may be over-doing it a bit, but just wondering if this configuration would provide any extra benefit.

Thanks,

Trey

Chris, a few questions about your response:

1. If I piggyback the SPP6 on the larger capacitor, do I just connect the wires from the SPP6 to the two different posts on the larger capacitor?
2. Is there a way to wire the SPP6 as a compressor start capacitor for this a/c?
3. How would the SPP6E benefit me more in this scenario? How would it be hooked up to the A/C with the existing capacitors?

Thanks,

Trey

Good thing you asked!

See if you can swap that SPP6 for an SPP6E and continue to march. The 6E's two leads will go to the extra terminal blades on that large capacitor. One where RED already is, the other where Yellow and White already are.

Our Coleman Mach HAS a Start Cap and a Start Relay. The Cap is black plastic and next to the small Fan Run Cap. The Relay is above the Start Cap. Four components total, yours currently has two. The SPP6E provides the same effect as the combination of Start Cap and Start Relay. And wired as Chris noted and as I added the colors from your photo.

Be sure the POWER is OFF, and it's a good idea to short across the terminals of a capacitor you're going to handle. I think the motors they're connected to will bleed the charge off, but a cap is a charge storage device, so why take a chance?

Stop- the Supco doesn't replace anything in yours- you do not have a start capacitor installed. The small capacitor is the fan capacitor, the larger is the compressor run capacitor. The Supco will simply piggyback on the larger one.
I don't recommend the non-E version. It is fine- but it's identical to the factory start kit, and provides no extra benefits for generator use.

Bob, thanks for the reply. Regarding the connections, since both of the connections from the spp6 are black wires, does it matter which black wire is connected to the dark brown wire and which one is connected to the light brown wire? I'm assuming I connect one black wire to the dark brown wire, and the other black wire to the light brown wire, and then I'm good to go.

I believe you are correct. (small one). First trailer I replaced the small one, second trailer only had the large one so I piggy-backed it to the large. BTW, the SPP6 (without the E) is what is recommended by Suppco so you should be good to go.