AC Compressor Temp

[Hawkshaw1]

Can someone give me some insight on how warm the AC compressor should be on a Marine Air 16,000 btu unit? The unit works and cools but the compressor is warm enough that you can't hold your hand on it for more than 5-10 seconds. The pump is working and water is flowing out the thru hull.

Another issue to me is that it pull air from under the bed thru a filter in the bed frame which essentially means it's pulling it from the hull/bilge. Well, my hull is a little stinky (I'm working on that). Does it have to be that way to cool it or could I try to pipe the air to the unit from the vent so it doesn't pull air from the bilge?

Thanks in advance.

Hawk

 

[rslifkin]

Those compressors getting that hot is normal. As far as return air, as long as an adequate quantity of air is getting to the unit, it doesn't really matter how it gets there.

 

[Hawkshaw1]

Thanks for the reply. I am so new to all this it's hard to know what's normal.

 

[rgano]

Perhaps you can use some foil covered foam to build a duct from the intake grill to the ac unit to avoid entraining the bilge air.

 

[DavidM]

The compressor heat is normal, but maybe not the return air source. Generally A/C units mounted underneath the bed draw air directly from a grill in the bottom of the bed frame ducted directly to the A/C and do not draw air from the general under bed cavity which apparently includes the bilge.

Hard to say what to do not knowing your geometry, but Rich above is on the right track.

David

 

[Hawkshaw1]

I found this. I think I'll see how to seal the area where the unit is under the bed to isolate it from the bilge. I also think I am going to need to replace the hoses to the tank.

Return air ducting:
There is no need for return air ducting – these units are like vacuum cleaners, sucking air from whatever compartment they are in and blowing the cooled or heated air through the discharge duct-work system. If you use our pre-designed ducting system you will be assured of having the correct amount of air flow and air velocity to successfully de-stratify the air in a properly sized application without having excessive noise or uncomfortable drafts.
The blower motor and rotary compressors are air cooled and do get warm, therefore it’s good form to have the return air travel over these components in route to the evaporator. There is no need to have the evaporator up against the return air grill, in fact, it’s better to have the opposite – make sure the evaporator has at least 2-3″ of space from a bulkhead.
We manufacture vertical or side discharge units – although it is possible to change this after production it is difficult to do so and we don’t recommend it.

 

[Rufus]

As the literature says, the suction inlet should draw air from the area being cooled so that the unit is constantly recirculating and dehumidifying air that has already been cooled...same as the recirculation feature on an automobile unit...much faster cool down and almost certainly easier on the unit. Pulling humid air out of the bilge is odd.

 

[Hawkshaw1]

I am not sure it's pulling a lot of the air from the bilge but I don't think the area under the bed is really sealed from the bilge. I am going down to the boat today and check that out.

 

[rslifkin]

Easiest solution would probably be to just seal that area off better from the bilge, forcing all of the air to come in through the return vent into the space.