Running aircon from 16A supply. More advice?

  • Thread starter Thread starter Deleted User YDKXO
  • Start date Start date
Couple the aircon up to something along the lines of a Victron Phoenix Multi Plus ? Useful when power consumption exceeds genny or shorepower capacity for short periods. It will supplement the available capacity from a battery bank and then replenish when current is available, they are quite intelligent and will take only whatever power is available from shorepower after other consumers to recharge without tripping the 16a.
 
Try berthing in Palmazana or Korcula Town in July or August. You're lucky to get 1 x 16A supply
Aha, now I see what you mean.
'course if you look for the most "de rigueur" spots, and in the peak of the season, you're bound to have troubles! :D
But in Palmizana, you've got plenty of great bays around where to anchor. There's not a lot to see where the marina is located, anyway.
Re. Korcula, well, the village is really worth staying there (and also the whole island: have you tried renting a scooter and driving around it?), but I'm afraid the only solution is to go there off season.
I've seen people fighting for a berth OUTSIDE the harbour wall, where I would NOT overnight if it were the last berth available in the whole Adriatic... :)
 
once the pump was running with one A/C unit, switching another A/C on only increased the overall electricity by a couple of amps.
Are you sure that the second A/C unit actually didn't use the same compressor?
I'm with jfm on the raw water pump, there's just no way it can draw 20A. If anything, J possibly overestimated even the 1hp...

I happen to have a pic of my pump motor, because I had it re-wired last year. You can see the specs below.
Ok, you surely have something bigger on your P67, but the one below is good enough for 2x17k BTU units, so just do the math...
Fasco.jpg
 
Not sure how useful this is but my boat was first speced for the med with 3x separate aircon units which overcomes the problem entirely as a is for bedroom 1, b is for bedroom two and diverts to saloon, c is saloon but needs boost from b on a hot day and bedroom 1 can also have the door left open if required. .

each one can be started in turn and all three will run together off a 16 amp supply.


I realize its too late to redo the whole boat but wouldnt two small (1500btu) units fitted be the ideal solution.

have the ducting made so it can be diverted to the cabins or the saloon.

I realize 3000 btu will not do a lot on a sunny day but evenings will be covered and you still have the main unit for the sunny mid day.


I dont have any experience in the med, before proceeding check with others.
 
Aha, now I see what you mean.
'course if you look for the most "de rigueur" spots, and in the peak of the season, you're bound to have troubles! :D
But in Palmizana, you've got plenty of great bays around where to anchor. There's not a lot to see where the marina is located, anyway.
Re. Korcula, well, the village is really worth staying there (and also the whole island: have you tried renting a scooter and driving around it?), but I'm afraid the only solution is to go there off season.
I've seen people fighting for a berth OUTSIDE the harbour wall, where I would NOT overnight if it were the last berth available in the whole Adriatic... :)
Yup I know there are plenty of lovely anchorages in the Paklenis around Palmazana but when you've got guests on board who want a night out in Hvar Town, really the only option is to moor in Palmazana ACI and take the water taxi. IMHO, the channel between Hvar and the Paklenis is too wide and potentially choppy to safely take a dinghy across. Thanks for the heads up on Korcula. Yes, it gets very windy in the channel between Korcula and the Pelgesac peninsula and there's no way I'd berth outside the harbour wall in Korcula Town ACI either.
Its going to take us a lot longer than the 2 seasons we have had there to find our favourite places:)
 
Are you sure that the second A/C unit actually didn't use the same compressor?
I'm with jfm on the raw water pump, there's just no way it can draw 20A. If anything, J possibly overestimated even the 1hp...
I tend to agree with that. The raw water pump on my boat is rated at 0.37kW
 
Couple the aircon up to something along the lines of a Victron Phoenix Multi Plus ? Useful when power consumption exceeds genny or shorepower capacity for short periods. It will supplement the available capacity from a battery bank and then replenish when current is available, they are quite intelligent and will take only whatever power is available from shorepower after other consumers to recharge without tripping the 16a.
Thanks David but that is my solution no 1 already. The problem is that the Multiplus cannot charge the batteries at anywhere near the amperage rate that the aircon is going to consume so it's going to flatten the batteries fairly quickly. However we are doing some more tests on my boat to determine the current draw with only the cabins aircon switched on to see whether the current draw is significantly less which might make the Multiplus viable. The Multiplus is certainly the cheapest solution for me and it takes up the least space
 
Are you sure that the second A/C unit actually didn't use the same compressor?
I'm with jfm on the raw water pump, there's just no way it can draw 20A. If anything, J possibly overestimated even the 1hp...

I happen to have a pic of my pump motor, because I had it re-wired last year. You can see the specs below.
Ok, you surely have something bigger on your P67, but the one below is good enough for 2x17k BTU units, so just do the math...
Fasco.jpg

Yep - I appreciate your and JFM's point about the pump load.
But I definately saw a huge load when I switched the pump on.
I cant remember but I'm prety sure that the old Sealine installation had four seperate A/C units and the extra load after the initial one was swiched on was minimal.
I should have the opportunity next week (on a friend's boat) to check what this extra load was.
I will find out - for my own peace of mind anyway.
 
Yes, it gets very windy in the channel between Korcula and the Pelgesac peninsula and there's no way I'd berth outside the harbour wall in Korcula Town ACI either.
It's not just that it can be windy, it's the odd ship or ferry crossing the channel that can make any boat moored outside the wall - even very big ones - move unpredictably, to the point of hitting/damaging something.

Re.Hvar, I see what you mean.
One alternative you might wish to try is Vrboska marina, in the N side of Hvar island.
It's nice and well sheltered, and the road from there to downtown Hvar is very nice to do with a scooter.
Or just use a taxi of course, particularly if you have guests.
 
I realize 3000 btu will not do a lot on a sunny day...
LOL, I'm afraid that 3 thousands BTU will do close to nothing.
You seem to have lost one zero in the keyboard, with both the 1500 and the 3000... :D
 
The last time i was there (2010 iirc) they stopped permission for any boats to use the outside wall at Korcula, MapisM, when Bora was expected. So the big anchorage just around to the east was much fuller. A few years ago I spent a windy night there; never again. In a Bora it is best to leave the marina and run about 1nm to the east, and you get a nice calm anchorage in the lee of a big island

I agree Deleted User that crossing the channel at night in a 3m tender to get to Hvar town is too dangerous. I'd do it in a big tander but not in a 3m dinghy full of guests. Better to use the marina and water taxi. It's a particularly nice marina anyhow, imho
 
In a Bora it is best to leave the marina and run about 1nm to the east, and you get a nice calm anchorage in the lee of a big island
Yup, agreed.
Actually, along that NE coast of the island there is also another small marina called Lumbarda.
It's not well know, and a taxi is necessary to go to the town, but it's an alternative anyway.
Though tbh I used it more with my previous 34', 'cause for a 53' it was already VERY tight.
Therefore, unless they enlarged it in the meantime, that's not an option for bigger boats.
 
Last edited:
Yup, agreed.
Actually, along that NE coast of the island there is also another small marina called Lumbarda.
It's not well know, and a taxi is necessary to go to the town, but it's an alternative anyway.
Though tbh I used it more with my previous 34', 'cause for a 53' it was already VERY tight.
Therefore, unless they enlarged it in the meantime, that's not an option for bigger boats.
Yes thats correct although when we looked in there last year, it looked quite run down and not very pleasant. If a Bora was forecast and Korcula ACI was full, I think I would rather go on to Mjlet and anchor in Polace or better tie up to one of the restaurant quays there
 
...provided no one touches the pins of one plug whilst the other is still connected.
Yeah, we discussed that in the thread linked in the OP.
We also assume that nobody sticks his/her tongue in the dock socket to find out which is the hot wire, of course... :D
 
However we are doing some more tests on my boat to determine the current draw with only the cabins aircon switched on to see whether the current draw is significantly less

good idea Mike, to investigate the exact consumption of your systems, and get to know where the relatively high current comes from.

I have a similar system like jfm, and can run the airco with just one compressor (from two) switched On, on a 16A supply,
and still have some headroom for lights.

both compressors operate on one common cold/hot water distribution system, and one common seawater pump.
no valves, no programming, just a On/Off switch for each compressor, very simple.
so maybe It should be possible to make a similar setup in your boat, and add a smaller Airco unit. A good airco man can tell you for your particular boat.

a 4the solution is buying another boat :)
 
Top