New Sportfish CAT Design

[NeumannKG]

I'm currently in the middle of designing a 43' sportfish catamaran and am planning to equip it with an enclosed, air-conditioned pilothouse. Because of the A/C load, I'm considering adding a small diesel genset to power the HVAC system.

This will be my first time incorporating this type of configuration into one of my designs, so I'd love to hear from anyone with experience. I'm interested in recommendations on genset sizing, A/C capacity, installation considerations, noise and vibration isolation, fuel consumption, maintenance access, or any lessons learned that you wish you'd known beforehand.

Any suggestions, best practices, or pitfalls to avoid would be greatly appreciated. Thanks in advance!

 

[bajansailor]

Welcome to the Forum NewmannKG.

Re gen set sizing and A/C capacity, wouldn't this be dependent on how big the deck house is?

I presume that your cat will have petrol outboard engines - or will they be diesel, or inboard engines?

This 45' Grady White has outboard engines, and a 12 KW diesel generator - they mention that she has a 12,000 BTU air con system for the cabin and I think that this has vents in way of the open helm console as well.

https://www.gradywhite.com/models/canyon-456/

Owners will have to be careful that they do not confuse the fillers for the water, diesel and petrol.

 

[NeumannKG]

Welcome to the Forum NewmannKG.

Re gen set sizing and A/C capacity, wouldn't this be dependent on how big the deck house is?

I presume that your cat will have petrol outboard engines - or will they be diesel, or inboard engines?

This 45' Grady White has outboard engines, and a 12 KW diesel generator - they mention that she has a 12,000 BTU air con system for the cabin and I think that this has vents in way of the open helm console as well.

https://www.gradywhite.com/models/canyon-456/

Owners will have to be careful that they do not confuse the fillers for the water, diesel and petrol.

Thank you.

Correct.. The pilot house will be around 200sqft. The I am thinking 8k BTU because aluminum hose and windows all around. So, the electrical load plus hotel load i think i can get away with a 6kw. I was thinking about dometic style AC but someone suggested a split but i only have experience with air cooled split. No one wants to have condenser on the deck of a 1.2mil boat. I was thinking water cooled but don't have experience with that design or operation. Additionally, you are correct the Mains are regular fuel and the genset would be diesel.

 

[bajansailor]

I am sure that other folk who know a lot more than I do about this subject will stop by this thread soon, and I hope that they will also offer opinions.

In the meantime can you tell us a bit more about the design of your new power cat please?
It sounds like an interesting project.