Reverse Cycle Air Conditioning

[Paul and Judy]

I am considering installing a EnviroComfort reverse heat/cool air conditioner. This unit draws water from a through hull fitting. My question is: is it acceptable practice to T-off an existing through hull fitting. I was thinking I could use the through hull fitting from the cooling system to the engine. The Air unit has its own water pump. The Air unit would not be running at the same time as the motor, so I'm thinking this may not be a problem. Any comments ??

 

[Jon Bastien]

I don't think I'd 'Tee' this off of the engine coolant-- If the engine were to pull the water back out of the line from the AirCo unit, it could suck air into the engine's cooling system (severely reducing its effectiveness...).

I initially thought you may be able to 'tee' into a sink drain, but then you could get air in the AirCo's water line from the sink side. Maybe a head intake line would work...

I think I'd just go with the dedicated thru-hull.

 

[Snotter]

Put an in-line seacock between the engine coolant hose and the AC raw-water pump. Turn the valve off when using the engine.

 

[al4b]

Jon is right. Never share any critical system resources, like the engine. A valve is guaranteed to be forgotten. Best is to use a dedicated seacock. Never share a drain you will draw used water into the AC, soap scum, hair, left over soup…. You may get away sharing a head water intake for now ... until the boat is out of the water.
Alain

 

[Paul and Judy]

Snotter - I already have a thru hull seacock to the engine. Are you saying I should install another seacock in the line going to the engine? I am having trouble visualizing this, is there a tee at some point in the line?
Please clairify, as I am confused.
Thanks
Paul

 

[SVCarolena]

Here is what we did to avoid installing a new thruhull: We upgraded our head to draw raw water from the sink drain. We view this as an upgrade, as it allows us the option to flush with raw water or fresh (fresh is great for the end of the weekend to make sure there is clean water in the system that won't stink when sitting all week). That freed up the intake for the head, which is now the intake for the AC. I thought about the engine route you mentioned, and had I gone that way, i would have installed a valve to direct the water to either the AC or engine, but not both, to avoid any air being sucked into the system, but the head route made a lot more sense, was very simple, and avoids the problem that was mentioned about potentialy forgeting to switch the valve before starting the engine.