AC in forward cabin

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Gypsymagic

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Aug 24, 2011
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54
Vessel Make
1996 Grand Banks 42 Classic
When I purchased the GB 42 C It did not have an AC in the forward cabin. Now cruising in Florida I’ll need one. Any suggestions of installation locations using a self contained unit and what BTU are needed? Can you vent it to the forward head? Etc.

Thanks
 
We have a 1200 BTU in the forward cabin and a vent is run to the head just above the sink and to the right. The unit is under the V Birth. We have a '93 42 Classic
 

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So far I have had good luck with my Webasto self contained units. I run them 9 months out of the year in heat mode and 2 months in cooling mode. I only have 4 years of experience with them.
 
We have a 1200 BTU in the forward cabin and a vent is run to the head just above the sink and to the right. The unit is under the V Birth. We have a '93 42 Classic
Thanks for prompt reply and picture, 12000 btu sounds like a lot for the cabin/head. Does it work well ?
 
Thanks for prompt reply and picture, 12000 btu sounds like a lot for the cabin/head. Does it work well ?
Yes it does work well. We are in Charleston, SC so it does get used.
 
Be mindful of the kind that use raw water with long hoses. You introduce another maintenance hassles of getting the hoses cleaned when gunk grows in them. I had a 3rd unit added for the heads/starboard berth in our EB47 and that's an issue when the water gets warm. Had I known I'd have gone with a unit like the kind in there already, where the raw water hoses are short and it's just refrigerant lines that run to the air handler.
 
@wkearney99 sounds like you are describing a split system. These are nice but have a different set of challenges with refrigerant needing to run through your boat. Copper tubing with insulation so subject to corrosion and leaks. Also requires a separate air handler in the compartment.

Not advocating for either option (have had them both) but if doing a self install I think the stand alone is the more practical choice. Usually significantly less $$.
 
You're running something regardless of the type. Either long runs of seawater from/to through-hulls, or the refrigerant lines. Installing AC lines is not rocket science and corrosion is no better/worse than anything else in the boat. Both require an assembly to push the air. A split system requires two, but runs only copper tubing between them. This was my point, seawater lines WILL get clogged with growth, especially in warmer months. This adds a maintenance hassle that you don't get with a split.

Buy once, cry once. Either spend it up front and it's set-and-forget, or have it nickel and dime you every season dealing with hoses getting gunked up. Easy to install is nonsense if it's going to load you up on the backend with having to use acids to clean the hoses.

There is a third option, to use a chiller setup, but that's a whole other scenario outside the scope of what's being asked.

There are indeed pros/cons to both. I try to look at on-going maintenance costs as being more important than low cost of entry.
 
You're running something regardless of the type. Either long runs of seawater from/to through-hulls, or the refrigerant lines.
To me the ideal is having a dedicated through hull and raw water pump for each unit. There are arguments against this, but it is another option.
 
To me the ideal is having a dedicated through hull and raw water pump for each unit. There are arguments against this, but it is another option.
The downside being more holes to present leaking problems. But it can get you shorter hose lengths. Also consider that not everywhere under the hull is ideal for an intake pickup, or offers a convenient place to reach a shutoff valve.

I have my three main units fed through one intake/outlet via a manifold setup (that's oversized for the flow load). The added unit was not done with my consultation (STAY ON YOUR CONTRACTORS) and could use larger hoses as a means to combat the growth problem (or at least delay it's impact).

My point is know what the different trade-offs gets you into.
 
I have an extra intake valve right at the forward engine bulkhead which is not being used. I suspect it might have been a past forward head intake point. Anyway, I plan on using it, add a filter and run a small independent pump. The outlet will likely go to the old manual bilge pump (removed) outlet which is shared with the forward shower sump pump. My only concern is a possible back flow from the AC pump to the shower outlet hose. I’m still reviewing this topic.
Thanks all for the comments.
 
Being my new boat to me a 1996, it’s had it shares of different electronics added over the years. However, the installers, always leave all the old wiring. I’m now cleaning up and removing and replacing it with current electronics. Unfortunately I’m left with numerous holes at the lower station overhead compartment face (center and starboard).

Has anyone replaced these teak panels? Or resurfaced with teak veneer? Or any other options?
I’m not sure if they can be simply removed and replaced without major carpentry work.

Thanks
 
I have an extra intake valve right at the forward engine bulkhead which is not being used. I suspect it might have been a past forward head intake point. Anyway, I plan on using it, add a filter and run a small independent pump. The outlet will likely go to the old manual bilge pump (removed) outlet which is shared with the forward shower sump pump. My only concern is a possible back flow from the AC pump to the shower outlet hose. I’m still reviewing this topic.
Thanks all for the comments.
I generally never like sharing an outflow with anything else. Especially not an AC system where the pump moves A LOT of water. If whatever else is one the line fails you'd have a powered source of seawater getting pumped into the boat. I would not put the safety of the boat at risk of a powered AC pump putting backpressure on a sump drain pump.

With AC systems sharing through-hulls they're at least 'closed' in that if any shared pumps failed that's still an overboard connection, not the other end of an open drain on the inside of the boat.
 
If you have more than one sharing an outlet, be sure EACH one gets winterized (if you do). Pink coming out discharge is not sufficient.
 
If you have more than one sharing an outlet, be sure EACH one gets winterized (if you do). Pink coming out discharge is not sufficient.

Yep, things backflow gizmos are notorious for allowing just enough water to remain in them to freeze and burst.
 
2 of my 3 A/Cs share a pump and I've never found it hard to get them winterized. On my setup there are no check valves or anything, so both of those units get full water flow any time either (or both) of them is calling for the pump to run.

The process for me is to start one of the units, open the sea strainer lid (which will start to overflow). Then close the seacock and start pouring antifreeze into the strainer. The admiral watches the discharges and once both of them go from clear to pink, she lets me know she's about to shut the system off, then turns off the A/C (by which point I've fed a bit more antifreeze through to continue displacing any diluted mixture out of the system, as the walk to the controls, shutoff, etc. takes a moment). Then once the boat is out of the water, re-open the seacock to allow any trapped water to drain.
 
Backing up a few steps.... I wouldn't bother running a vent to the head. That door is only closed when the head is in use or when the starboard berth is in use. My forward AC unit is under the port berth, discharges through the cabinetry above/aft, and has no difficulty keeping that compartment comfortable.
 
Yes it does work well. We are in Charleston, SC so it does get used.
I put in an 8K BTU self contained Dometic in my v berth; I have a 16K in the salon and another 16K in the aft cabin of a 1985 42 classic. 8K is really not enough... It will get cool but it takes hours versus the salon and aft cabin that cool withing 5 or 10 minutes.
 
When I purchased the GB 42 C It did not have an AC in the forward cabin. Now cruising in Florida I’ll need one. Any suggestions of installation locations using a self contained unit and what BTU are needed? Can you vent it to the forward head? Etc.

Thanks
I had 46 and AC was located beneath V-berth. You're right, you need AC. I replaced all of mine (3) with 16K. Came with 16 in salon, 12 in v-berth and 12 in master. I also got the darkest tint I could get on all windows.
 
When I purchased the GB 42 C It did not have an AC in the forward cabin. Now cruising in Florida I’ll need one. Any suggestions of installation locations using a self contained unit and what BTU are needed? Can you vent it to the forward head? Etc.

Thanks
I have a GB 42 also. Your choices are under the Vee-berth as suggested. In the hanging locker or under the counter in the head. Look carefully at the plumbing and electrical runs and decide which would be easier for you.
 
Being my new boat to me a 1996, it’s had it shares of different electronics added over the years. However, the installers, always leave all the old wiring. I’m now cleaning up and removing and replacing it with current electronics. Unfortunately I’m left with numerous holes at the lower station overhead compartment face (center and starboard).

Has anyone replaced these teak panels? Or resurfaced with teak veneer? Or any other options?
I’m not sure if they can be simply removed and replaced without major carpentry work.

Thanks
I have used 1/4” black Starboard to make new panels.

I would not share the discharge from the A/C with another discharge. It is easy to drill another hole and keep them separate. And safer.
 
When I purchased the GB 42 C It did not have an AC in the forward cabin. Now cruising in Florida I’ll need one. Any suggestions of installation locations using a self contained unit and what BTU are needed? Can you vent it to the forward head? Etc.

Thanks
Whatever you do, avoid Marinaire in Ft Lauderdale. I bought 2 units from them, 1 from formerly Mermaid Manufacturing in Ft Myers. The second Marinaire unit was dead out of the box, they fought me on providing a replacement part, then sued me after the unit continued to fail and I asked for warranty support in the form of either replace or refund the unit with return. Here's the link for the Ft Myers company, the unit was a painless install, performed beautifully and could be vented to more than one location with a duct split. Home Page
 
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