Air conditioner grills

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tomsboat

Senior Member
Joined
Aug 18, 2015
Messages
113
Location
Bronxville
Vessel Make
Mainship Trawler
I have a 40 ft mainship trawler I just installed a 12000 BTU AC unit in the forward compartment and want to put a bigger grill there anyone know where to find one.Tom
 
Have you looked online? Lots of them there. If you want a custom one, I think Mermaid Airconditioning makes them and Boat Outfitters does also.
 
Return air grill or supply air grill? A bigger supply air grill requires installing a new duct box and usually a bigger duct to supply more air.

What is the problem? Not enough air? Measure the return air temp and the supply air temp at the grill after the A/C has been on for 10-15 minutes to stabilize. If more than 15 degrees difference you usually don't have enough air flow and that might lead to icing up the evaporator. You need to increase duct and grill size to increase the air flow.

This outfit supplies most everything: https://www.suremarineservice.com/Cool/Grilles-and-Ducting/

David
 
AC grill

I just put in a 12000 BTU in the forward compartment on a 40 ft Mainship trawler the chart shows a 12000 but should have a 130 sq in return and a 70 in supply my return is 117 in and supply is 57 that's 2 grills.MY 18000 should be 200 return and 100 supply.Its 160 return and 65 supply that's 2 grills combo on the supply grills.Has anyone done any changes on there grills or are AC units working good with the Mainship installations?
 
return grills

I found the grills I have on my boat at Aquaair marine. Tom
 
Mainship notoriously ignored installation requirements from 3rd party equipment suppliers; look at refrigerator ventilation, air conditioning inlet and outlet ducts, windlass elec requirements, isolation xfrmr grounding requirements....
 
Mainship notoriously ignored installation requirements from 3rd party equipment suppliers; look at refrigerator ventilation, air conditioning inlet and outlet ducts, windlass elec requirements, isolation xfrmr grounding requirements....

I had only two of these beefs on my 2006 34T.

The lack of fridge ventilation was intentional, but in the mild climate of SoCal it cooled ok.

The lack of isolation transformer grounding was installation incompetence not cost saving because it took 2 minutes to rewire once I found the cause on my 34T.

Don't know about windlass elec as mine seemed fine- big enough wire and clean installation. I didn't have factory A/C on my boat and would never buy A/C from the factory again- been there done that and much prefer local installation, so I understand this beef.

David
 
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