A/C INSTALLED

[FIMAN1]

Is a RV dealer the best place to have a roof top AC installed?

[thataway]

I would say NO. RV dealers don't understand the structural issues involved with the boat. They don't know how to seal the core with epoxy. They often use wire nuts, instead of a proper marine crimp fitting--see below ref wire type.

It is a bit more than just cutting the hole. Although, you can cut the 14" square hole, I do believe it best to square up the top--at the very least, so that the gasket has a level surface to compress on. RV's have a fairly level roof, with less crown than the C Dory.

Here is a photo of the top strengthened and faired level for the upper gasket of the RV AC unit on the Tom Cat 255. We laid strips of glass cloth and epoxy to build that surface.



The underside, wood cut to the contour of the underside of cabin roof, for the air handler athwartship pieces clamped and epoxy glued in place:




The final product inside, before air handler installed:



The boat should already have 120 V AC power installed and a separate breaker for the air conditioner. The wiring is usually run up the inside by the aft dinette seat, or can be run from up forward along one side of the window pillars. One should not use Romex house wiring, but 12 gauge tinned copper marine wire (3 conductors, neutral, hot and ground).

Get a marine contractor who understands the marine requirements.

[srbaum]

What size boat do you have?

[FIMAN1]

I'm looking at a 22.

What other options for AC are there?

[ssobol]

Wally World window 5K BTU AC unit placed in the center opening window.

[thataway]

Agree, with the window AC. We have used the 5000 BTU Arctic King or similar on two 22's and two 25's. We find it will bring the temp down to 20* below ambient--but you may want to put the Milar coat bubble wrap inside of the windows to give some insulation (we use this on both the 5000 bTu and the 9200 BTU RV roof air. used on the Tom Cat)

We are still in limbo about putting a RV roof air on the current 25...The reason is that we like to carry the dinghy on the roof...also limited interior cabin roof space--because of a storage rack under the overhead. The negative with the 5,000 BTU AC window unit is placing it in the window when you want to cool the boat. Since I am in my 80's and have back problems, it is wise for the two of us to lift the AC unit in place. We fitted fold down metal handles on each side--and that helps. There are wooden runners on the bottom, which also helps...We have run with the AC in place, but for only about 30 miles, and mostly at displacement speeds--with my wife double checking the visual to the port side....sort of awkward--and not something I would want to do often.

Unfortunately the roof size opening for the RV AC unit is 14" square. It would be nice if there was an opening hatch which would fit that dimension--but we would consider putting in a 12" square marine hatch in a Starboard frame of about 18" (allow 2" flange around all sides), so it could be run without the roof AC. The Roof AC's weight is about 90#, so we would have to use our dinghy crane davit to hoist it in place...Doable, but not easy.

[srbaum]

FIMEN1,
If you purchase a 22, the roof is strong enough to mount a small low profile AC without building up the inside or outside of the overhead. The overhead (roof) is solid fiberglass. The AC comes with thick foam pads that you can cut to the shape of the overhead. The AC takes a standard size rooftop AC square hole to mount it.
If you need specific instructions, I can walk you through it.

[thataway]

[srbaum]

The foam is dense enough and thick enough to cut a crown in it and by doing this, it does not cause distortion to the fiberglass.

[thataway]

Good to know. The Coleman 9200 I had in 2007 had foam which was not suitable for cutting and making a crown.

[gulfcoast john]

We’re in the same (well similar) boat…102 degrees on the beach today. During our 2 hour beach walk we happened upon a new sea turtle nest 3 miles past the end of the road and other people; she crawled up last night and you can see her tracks and the Ranger’s tracks where he installed the sign and chicken-wire (to help keep raccoons etc from digging up the eggs).
Sensing a unique opportunity, our 2010 Coleman rooftop AC decided this would be a great time to seize up, not just because it’s a bit hot, but we plan on leaving for the next Adventure (loop of Erie, Rideau, Richleau, Chambly and Champlain historic Canals plus the Finger Lakes) in 2 weeks. Bob’s most helpful (as always) reply to my earlier PM re RV service is spot on. They don’t want to touch it, and if they do touch it, it won’t be for 2 months after Parts receives the new unit at RV Retail prices, plus $300-$600 min labor. Every topside bolt and screw on this unit is rusty and seized or stripped (no surprise as often the entire roofline has been soaked in saltwater on a ‘sporting’ outing). We don’t have many but boy, are they memorable.
If my measurements are correct (probably not) an LG LW6017R 6k BTU window AC might fit, the only 6k unit I could find that might. If it does, I will brag about it here. If it don’t, I will silently slither away as usual.
If the window unit interim fix (which may work fine in Canada/NY/Vermont in August) works, our plan is to tear off the old unit on return and try to replace it with one in the Bob Austin proper fashion. Wish us luck!

[img]http://www.c-brats.com/albums/CAT-O-MINE/turtle_nest.thumb.jpg[img]

Cheers!
John, still no luck posting pictures, someday I must commit a full 20 minutes to learning this...but we're busy!

[Sea Wolf]

[thataway]

John,
I don't know if you can get any of the bolts loose for access--but I would cut them with a cut off wheel, if you want to remove the the old unit. A small Dremel tool, and flexible shaft will work to get into tight places.

When the new uint is put in place there are ways to prevent the rust--or at least minimize it. Coat with a never seize at the time of installation, and spray the metal nearby with H&M CB12 Corrosion Block. When you do the annual inspection of the AC unit, insitu, give another squirt of the Corrosion Block at the time of inspection.

As I understand it, you are going to scrap the old unit anyway.

Not sure about the 6,000 BTU AC, but I found almost an exact duplicate of the 5,000 BTU unit I have, at either Lowes or Home Depot. I can get the measurements of the window unit, and show you the handles, wooden runners etc.

[BTDT]

FWIW-

I installed a Colman power saver model on my Tomcat several years ago. I chose to position it on the roof between the Captain's and Admiral's position for several reasons; the roof appeared stronger in that position, the air flow permits rapid defrosting of the windshield, enhanced cooling of the Admiral (very important), and there's still sufficient room to slip an inflatable dingy over it if need be.

After removing the 14 inch plug I was so impressed with the C-Dory roof construction I chose not reinforce the roof, and instead used a metal plate and thick compression gasket to accommodate the slight curvature of the roof. Several years and many heavy rains later we have experienced zero leaks nor any evidence of hairline cracking.

Had I to do it over again I would not have chosen the Coleman product because of their updraft fan design. While the unit cools great and is t quiet for those inside, the exterior noise is a bit much for nearby slip users, especially late at night

[Snider]

We slept on the boat anchored out Saturday night. Best quote from my 7 yo daughter, "Daddy it's too hot to live" haha. We were in Edisto SC, upper 80's during the day, upper 70's at night, heat index 90's and 80's.

I've been contemplating the window AC. We anchor out mostly and honestly CO has been a worry. Really need to install some fans and a screen for the door as well as window curtains. Thought about getting the AC and utilizing a slip more during the summer. Honestly though, with a little better ventilation and some fans it may not be too bad. I slept terrible mostly because I was worried about the kids and where we were anchored, the heat was bearable.