Air Conditioner condensate drain

Jun 21, 2004
1,910
Beneteau 343 Slidell, LA
I would appreciate some advice on how to best handle air conditioner condensate that is presently flowing into my bilge. The previous owner of the boat had a marine contractor install a Cruisair emarld series reverse cycle heat pump on the boat. It consists of a condenser mounted under the forward berth, a 12K btu evaporator installed in a forward cabinet that supplies air to the forward V berth and the salon, as well as a 4K btu evaporator that is installed in the lazerette that supplies the aft berth. The forward evaporator condensate drain is plumped into the condenser cooling water outflow via a "condensator" unit. It works well. The problem is that the aft evaporator is plumbed with a drain into the bilge. That is a problem for me; I want to eliminate the drainage into the bilge.

Seems to me that I have three options:
1. Run a line from the aft evaporator to tie into the forward condensator
unit. I am not sure that this would work as it will be about a 30 ft run.
I don't think that I will get enough gravity flow and I doubt if the
condensator will pull enough vacuum to keep the flow sufficient.
2. Install a self contained shower type pump with auto float switch and
vent it out the side of the topside near the water line.
3. Run a line to the nearby head lavatory drain and "T" into the drain line
to allow gravity drainage.

What do you think would be the best way to eliminate drainage into the bilge??
 
May 16, 2007
1,509
Boatless ! 26 Ottawa, Ontario
I bought a condensate pump made by Mermaid from Defender.com, all brass, it spliced into the cooling water line and keeps the AC pan dry. No moving parts, it's an aspirator. It was expensive but was lucky enough to get it on sale at 50% off.

Defender have this one, http://www.defender.com/product3.jsp?path=-1|2276179|2061076|2061077|2061085&id=2756613

Similar to what I have but seems to have many more clamps and bits.

Many on here have bought a small plastic version of these from an aquarium, pond supply shop for about $14. They are happy with the results and you can't complain about the cost. The fittings obviously must be sized for the hose your AC pump is using, 3/4" ? Be sure to put a small filter on the water intake from the pan these aspiators are easily plugged.

I'm sure if you do a search on the forums you will find the older posts on this mod.
Good luck, Bob
 
Nov 26, 2008
1,935
Endeavour 42 Cruisin
AKA venturi.

Search for aquarium venturi and you will find a lot of them.

They are plastic and as such, I don't trust them under way. I never run the AC while under way so I'm not worried. When under way, I always shut the AC intake seacock and the overboard discharge valve which isolates the plastic venturi.

It sucks the pan DRY!
 
Jun 21, 2004
1,910
Beneteau 343 Slidell, LA
I have a venturi apparatus ('condensator") in the forward V berth area where the condenser/compressor is located. The forward evaporator unit is only about a 5 foot run to the venturi and condenser cooling water discharge. It works very well with no water accumulation in the pan or bilge. Problem is that the AFT evaporator is approximately 30 feet away from the condenser, water discharge, and venturi. The aft evaporator unit does not have any cooling water circulation; It only has refrigerant supply & return lines. (it is not a self contained unit). So, I don't think that I will get enough gravity flow and suction from the forward venturi / condensator to drain the condensate from the Aft location up and around cabinetry, etc. to the water discharge fitting.
 
Jun 21, 2004
1,910
Beneteau 343 Slidell, LA
Little Giant pump may be an economical solution to pump condensate from aft evaporator unit 25 feet forward to the "condensator"/ venturi and out thru the cooling water discharge.
Does anyone see a problem with just "Teeing" into the head/lavatory drain line and just allowing gravity drainage? The lavatory drain line is only about 5 feet from the AFT evaporator unit.
 
Sep 15, 2009
6,242
S2 9.2a Fairhope Al
That should work ....all you are wanting to do is get rid of it and not in the bilge. Go for it
 
Jun 21, 2004
1,910
Beneteau 343 Slidell, LA
Wood,
Is a nylon "T" and acceptable method of splicing into the lavatory drain line or should I use a combination of bronze fittings to make up the "T" or perhaps use stainless?
 
Sep 15, 2009
6,242
S2 9.2a Fairhope Al
use the nylon tee above the bronze ball valve i have one in my head feeding the phII water pump so i can pull sea water with the sink stopper in or pour fresh water in the sink with the ball valve closed ...i would suggest you close the ball valve when under way ...you wont be running the ac anyway.... i don't know why it would not work i got a heavy duty one from tractor supply for about 3.00 ...i did make sure that nothing was in a strain in the plumbing its all connected together with rubber hoses between each joint ...as i said the bronze sea-cock valve is the safety factor on the through hull and it is mounted like mainsail showed in his write up on groco flanges


PS
make sure the gravity draining is in the positive for your intended purpose...just run your drain line to where you want o splice in and pour some water in the drain pan and see if it flows to where you want to install the tee


HO..... and bronze is best but its a little on the over kill side for what you are doing
 
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Jun 21, 2004
1,910
Beneteau 343 Slidell, LA
Thanks to all for the replys. Think that I will try using the T in the lavatory drain line as it is the simplest & most economical way to go. If it is not satisfactory, I can always try the Little Giant pump. Woody, will shop around for a heavy duty nylon or SS "T" fitting. Not concerned about galvanic or salt water corrosion as it will be spliced into the rubber hose & will be used for fresh water from the sink and condensate from the air conditioner. Much Thanks.
 
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Dan_Y

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Oct 13, 2008
506
Hunter 36 Hampton
I built a sump (low profile plastic box) and plumbed a low profile Whale supersub bilge pump with the built-in electronic switch. It pushes the water out into a T in the head sink drain. Works great and because it is wired from the house DC side, it doubles as a second bilge pump if the primary fails. I considered a condensate pump like the one that's dumps water from my house crawlspace dehumidifier, but it's powered by 120 VAC. The sump needs to be only as deep as the bilge pump is tall.
 
Oct 2, 2008
3,631
Pearson/ 530 Strafford, NH
This is all above waterline, of course. We wouldn't want to hear the bilge pump running with the AC off.

All U Get
 
Apr 14, 2009
748
Sabre 28 NH
I'm not sure how your plumbing is set up but instead of splicing into the drain take a look at a dishwasher tailpiece.
 

PGIJon

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Mar 3, 2012
843
Hunter 34 Punta Gorda
OK.. I confess my ignorance... what is the problem with the condensation going to the bilge? -*** Name withheld.. -Jon (Doh!)
 

Dan_Y

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Oct 13, 2008
506
Hunter 36 Hampton
Our little 9 ton unit will put quarts of water into the bilge in 24 hours and the bilge pump leaves maybe 1/2 of water in the bilge...I like a dry bilge, especially around my keel bolts. It's so tight in the 30 that I had no room to drain... only into the bilge -so I placed the new sump there and got a second bilge pump out of the deal. Also tried the venturi suction device in the condenser water pump loop but it just wasn't able to pull the water about 12feet horizontally and up 3ft.
 
Jun 21, 2004
1,910
Beneteau 343 Slidell, LA
A wet bilge increases the humidity in the cabin and can cause mold growth & mal odors. There is also some evidence that a wet bilge can also contribute to hull blistering as both the exterior and interior are constantly saturated.
 

Gunni

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Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
You say the evaporator is installed in a lazarette? Not familiar with the layout of this Beneteau, but it seems like an above water line drain could be plumbed right out of the boat. A 3/8" drain would be plenty.
 
Feb 11, 2006
141
Hunter 34 Galveston,Texas
Our little 9 ton unit will put quarts of water into the bilge in 24 hours and the bilge pump leaves maybe 1/2 of water in the bilge...I like a dry bilge, especially around my keel bolts. It's so tight in the 30 that I had no room to drain... only into the bilge -so I placed the new sump there and got a second bilge pump out of the deal. Also tried the venturi suction device in the condenser water pump loop but it just wasn't able to pull the water about 12feet horizontally and up 3ft.
Wow! 9 tons of refrigeration on a 30' boat.Thats over a hundred thousand btu's. I'll bet you can store alot of meat and cheese on board.