Air Conditioning ReFit

[ArranP]

My catamaran 56ft had a central chiller system in the STBD engine bay supplying cold water to 6 blowers throughout the boat, 2 in the saloon and 1 in each berth.

This system is beyond repair and has been removed, however the hose for the chilled water is still in situ.

I am opting to install 4 self contained ac units, one in each berth.

So for the sea water there is an existing 1.5inch sea water cock and strainer in the STBD engine bay that the old central chiller system used and the hoses that fed the chilled water to each of blowers through the boat.

Question I am currently consdiering is do I utilise these existing hoses to run sea water from a single sea water pump to each of the ac untis ? Or do I put seperate sea water pumps and thru hulls for each ac unit.

[Tin Tin]

The AC units will have spec about how much sea water they need. We had a Lagoon where one sea water pump serviced two AC units, so I guess if your pump is up to the requirement that should be OK.

[ArranP]

Originally Posted by Tin Tin

The AC units will have spec about how much sea water they need. We had a Lagoon where one sea water pump serviced two AC units, so I guess if your pump is up to the requirement that should be OK.

Thanks.

There are pumps that have the required flow rate.... for the ac units that shared the same pump, did each ac unit have its own sea water exit thru hull or did they also share the same exit thru hull ?

[GordMay]

Originally Posted by Tin Tin

The AC units will have spec about how much sea water they need. We had a Lagoon where one sea water pump serviced two AC units, so I guess if your pump is up to the requirement that should be OK.

Indeed.
What are the individual [& total] AC units water flow requirements, in gallons per minute; and what is the pump's capacity, in GPM, and PSI [or feet per min velocity]?

[ArranP]

Originally Posted by GordMay

Indeed.
What are the individual [& total] AC units water flow requirements, in gallons per minuit; and what is the pump's capacity, in GPM, and PSI [or feet per min]?

3gpm per ac unit, there are pumps that do 12gpm.

[GordMay]

An 1-1/2" [full flow] inlet will provide about ± 81 GPM pumped @ 20➛100 PSI [about 12 Ft/Sec flow velocity], so, should be more than adequate to supply your [4] 3 GPM AC units [12 gpm total].

[ArranP]

Originally Posted by GordMay

An 1-1/2" [full flow] inlet will provide about ± 81 GPM pumped @ 20➛100 PSI [about 12 Ft/Sec flow velocity], so, should be more than adequate to supply your [4] 3 GPM AC units [12 gpm total].

Thanks.

Do I utilise the existing single thru hull in the STBD engine bay that was used by the old central chiller system for the sea water outlet, or should I make individual outlets next to each ac unit ?

[Tin Tin]

Originally Posted by ArranP

Thanks.

There are pumps that have the required flow rate.... for the ac units that shared the same pump, did each ac unit have its own sea water exit thru hull or did they also share the same exit thru hull ?

They each had their own exit through hull very close to waterline, I guess to reduce the noise.