Can I use a 30A splitter to power air con and AC power plugs?

[pdecker]

I just got my first big boat (Catalina 380) and it has one 30A input for the air conditioner and one 30A input for the the rest of the house, which powers AC outlets and the battery charger. My marina pedestal has only one 30A outlet per slip. The previous owner had two 30A outlets at his dock.

Q: Can I just power both 30A inputs with one cord and a splitter on the end?

[PamlicoTraveler]

As long as you are using a 30A connection to the boat, which you indicated you are, and not 50A. The previous owner may have had 2 30's and run a splitter from a 50A line to a pedestal.

[Cheechako]

Probably OK. If your needs are less than 30 amp total.... which they should be unless you have a big AC unit. How many watt AC unit?
Certainly a 20 amp house circuit will have a minimal AC unit and other things on it on it with no problem.

[pdecker]

I don't see a wattage rating, but it appears to be a Dometic 16000 BTU/hr unit that pulls 10.40 amps at full cooling load. I also note that the installed battery charger is rated for 40A, which looks like it may be a problem.

https://www.dometic.com/en-us/us/pro...specifications

[a64pilot]

Most Marina pedestals, have a single 30 and a single 50.
If so there are many splitters that will split that single 50 into two 30 amp cords, that’s your ideal and it’s very common too.

[CaptTom]

My boat has the same setup as yours; most loads on one 30A side, and the HVAC (and a few other loads) on another 30A side.

I use a 30A splitter to two 30A cords. My home dock has two 30A outlets, but I only use one, mostly because I'm too lazy to string two cords along the deck, and also to keep my other 30A cord out of the sun & weather.

I have a 50-to-30 splitter I can use if 50A is available, but I don't find the need to pay extra for 50A service at a marina. I can run two air conditioners at around 10 Amps each, and still use other appliances, staying well within the 30A limit.

During this past heat wave, I did have to forego running the electric water heater with the air conditioners working full-time, but that wasn't really much of an issue.

[basssears]

Originally Posted by pdecker

I don't see a wattage rating, but it appears to be a Dometic 16000 BTU/hr unit that pulls 10.40 amps at full cooling load. I also note that the installed battery charger is rated for 40A, which looks like it may be a problem.

Your charger is 40A @ 12v (assuming a 12v boat), so that's 480 watts or 4A @ 120v, so even with AC and battery charger going full blast that's still under 15A right there, you have 15A to spare for other power draws (although the AC may pull more amps for a few seconds on startup).