Two discharges thru one thru hull? !

B

Britanic

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My boat did not come with AC from the factory, it was dealer intstalled in 1988.
The condesation drain runs directly into the bildge, as some of you are aware, this was a common setup back then.

Well, I am sick of it. I am early to get in and late to get out and I don't have any water down there (spring and fall) until summer when the AC has been running.

I really want to run the line to the shower sump, but that would prove difficult. A more convienent set up would be to install another shower sump on the other side of the bulkhead where the AC resides, which just happens to be under the mid bildge pump thru hull discharge.

I am obviously concerned with creating a situation where the bildge pump cannot discharge the water and just sends it to the AC pan, there by possibly sinking the boat.

I am trying to avoid insatlling another thru hull in the boat. Is there a safe way to have two pumps discharge thru the same thru hull. Kind of like a "Y" with maybee even a check valve.

Or is this just a bad idea.
 
You could rig a check valve setup, but I personally wouldn't do it. At least not with a bilge pump or other device of importance. As far as I know, my AC does the same (drain to bilge), but my bilge isn't totally dry anyway (stuffing boxes and such), so I don't really care. Is it that big a deal to have the bilge pump run occasionally to drain the AC condensate?
 
a) in recreational boats, doubling up in a single thru-hull is not a good idea.

b) why not add a "shower" sump, then discharge into the -other- sump? ( I understand plumbing may be a challenge )

c) bite the bullet and add yet another in the hull for the new thru-hull fitting.

d) there may be another way: if you have a sink(s) that has it's own gravity drain thru-hull, you may be able to divert that sink to the new sump, then use that thru hull for the new sump discharge.
 
Try looking at the Mermaid marine site. They have something called a condenserator which is essentially a venturi pump that you install inline with your discharge from the air conditioner. A line then goes to your condensation pan and whenever the pump goes on there is a slight vacuum that removes all of the water from the. Really is a cool set up and costs a couple hundred from the factory.

Not very difficult to install at all.

Chuck
 
comptiger5000, A/C drains, for some reason seem to discharge "bio-active" crud ( mold etc ) into the bilge. Even though your bilge often contains some seepage from the stuffing boxes ( which should be your -only- bilge water source; fix the rest... )it is still not a good idea. In short, you can do it, but it is not a very good solution.
 
AC condesate is very prone to growing stuff... for lack of better word! you dont' want that in your bilge.

the mermaid venturi is an option, but i'm not crazy about taping into the raw water line... I'm sure these gizoms are pretty safe but...

forget check valves, they are going to get stuck, it's not a matter of if but when!

adding an above water line thruhull isn't a big deal, it can be done in water although that's one more thing to leave a streak on the hull side...

You can share a thruhull if you are careful and use common sense, especially since the condensate is low volume. One way to do that is to use a Y instead of a T and place is at the top of the rising loop, about a foot above the thruhull. secure the Y to the hull or a nearby bulkhead and put a piece of hose btween the bottom of the Y and the thru hull. Then connect both your bilge pump line and your sump to each leg of the Y at the top. Make sure all hoses are double clamped and supported so that you dont' put any stress on the thruhull (especially if plastic)

if you can't find a Y, you can use a T but make sure the bilge pump flow straight and connect the sump hose to the T since it's low volume. If using a T then make sure both line have rising loops above the T to prevent bakc flow.
 
quote:
Originally posted by Britanic

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Britanic,
I did something similar to what you want to do. Added a sump pump and tapped it into the drain line for my cockpit sink. My thru hull is about 2 1/2 feet above the water line. Also the sink and the condensation from the A/C is VERY low flow. It has worked great and my bilge is dry.

IMG_0009.jpg


IMG_0011.jpg


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Maybe I'll look into redirecting mine into a sink drain (unless A/C condensate goes to those "extra" through hulls that never seem to dump water and don't serve an apparent purpose). I've never had mold problems, but I agree that could be a concern.
 
Thanks everyone. As always - much appreciated. I'll let you know how it works out.

Bob P.
 
I think I'll have to dump some water into a condensate pan (the most easily accessible one) and see where it goes next time I'm at the boat, as I've sat here thinking, and I have enough extra through hulls to account for condensate discharge from all 3 A/C units. I have 13 through hulls (excluding engine and generator exhaust), 4 sinks, 3 A/C units, 3 bilge pumps, and 3 unknowns. I can definitely place 1 of them as close to 2 of the A/C units, but the other 2 aren't so close to the 3rd unit (but 1 isn't too far, either).

EDIT: I just remembered, I can pin 2 of the "unknowns" to my shower drain pumps (no sump inline). However, I still have the 1 "unknown" near my aft and salon A/C units (not close to the forward one). I'll dump some water into the pan for the aft one and see if it dumps over the side.
 
drilling a new thru hull is not a big deal if its above the water line. drill it from the inside using a core drill (uses a pilot hole in middle to steady the ring bit) an easy trick to controlling the mess is use shaving cream under where you are drilling. all the filings will get caught in the cream, then just wipe it up with a paper towel. no mess, no fuss. just check the hole and make sure you've drilled thru solid fiberglass. if there is a core, especially a wood core, you will need to seal that completely before installing the thru hull.
 
There is a product for multiple hoses using one thru hull.
My bayliner comes stock with a 2 1/2 inch thru hull that turns vertical and has a manifold on the top with 5 one inch barbs on it.
The shower sump and 4 bilge pumps are plumbed to this manifold.
I don't know who makes it but it is very heavy duty bronze.

Here is one by Groco that is similar but more restrictive than the one on my boat
dm5-1500.jpg
 
quote:
Originally posted by The Other Gary

There is a product for multiple hoses using one thru hull.
My bayliner comes stock with a 2 1/2 inch thru hull that turns vertical and has a manifold on the top with 5 one inch barbs on it.
The shower sump and 4 bilge pumps are plumbed to this manifold.
I don't know who makes it but it is very heavy duty bronze.

Here is one by Groco that is similar but more restrictive than the one on my boat
dm5-1500.jpg


Click to expand...


I think I saw somebody playing that in a band last weekend :D
 
Again, thanks for the replys.

It turns out I did not have enough height to install the "Y" in the mid bildge discharge.
I instead ran a length of hose from the AC condensate pan to the shower sump. I installed a brass nipple in the sump cover, and ran the hose through two bulkheads and three stringers.

Something I did not think of was condensation on the drain line, so I will have to go back and seal the openings in the stringers to keep them from rotting.

Cleaned out all the water in the mid and aft bildge where the AC water used to collect. I did this on Friday and ran the AC non stop, also cruised twice. I have to tell you the cabin smells fresh. It was definatly worth the work and only cost me ten bucks. After four hours of running I only had maybee a half gallon from the shafts - thats all the water I got down there the whole weekend. Normally I would pump out about 7-8 gallons on Sunday before leaving.

Very Happy
 
I tested my "extra" through hull. My aft AC (and probably salon AC, as they are next to each other) discharge condensate overboard. Not sure about the forward, though.
 
quote:
Originally posted by Britanic

Again, thanks for the replys.

It turns out I did not have enough height to install the "Y" in the mid bildge discharge.
I instead ran a length of hose from the AC condensate pan to the shower sump. I installed a brass nipple in the sump cover, and ran the hose through two bulkheads and three stringers.

Something I did not think of was condensation on the drain line, so I will have to go back and seal the openings in the stringers to keep them from rotting.

Cleaned out all the water in the mid and aft bildge where the AC water used to collect. I did this on Friday and ran the AC non stop, also cruised twice. I have to tell you the cabin smells fresh. It was definatly worth the work and only cost me ten bucks. After four hours of running I only had maybee a half gallon from the shafts - thats all the water I got down there the whole weekend. Normally I would pump out about 7-8 gallons on Sunday before leaving.

Very Happy

Click to expand...


Do not wait to seal those holes up in the stringers and bulkheads. Loose water on unsealed wood gets sucked up instantly!
 
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