Who uses a/c in the PNW?

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bowball

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I’m thinking I never used a/c in British Columbia north, except perhaps a few nights. There was that big heat wave a few years ago.

Is a/c now an essential to boating there given all the recent weather extremes or still an unnecessary one? East coast boats or maybe for Mexico but the PNW non Seattle?

Affects genset sizing too.
 
In the 10 years we have lived aboard, there really have been only a couple of days where we would have turned on AC, and that was last Summer in Seattle during the record-breaking 100-degree heat wave.

Even then, as we spent two days in Shilshole for a diver, it wasn’t as bad as we feared. Our main cabin did hit 90, but the slight marine breeze made the day manageable.
 
Never had AC so never used it in PNW or SE AK. Although....there are really hot days in either place that it would be nice. But not required. The temperature really drops when the sun sets, with the giant heat sink of cold water all around. Friends do have AC here in their boats but only because it was OEM with the boat when new.
 
Don't forget, need for A/C will depend on the boat just as much as the weather. Some boats are easier to keep well ventilated and comfortable than others.
 
@rslifkin, good point about ventilation. Sailboats are experts with that, but majority of powerboats are inadequate. Sorta like my house. No matter how many windows, the only way to get the cool night air inside is with a whole house fan to force it.
 
My boat was built in the PNW, Laconner, WA. It came equipped with a 48K BTU chiller A/C system. Probably because the saloon, galley and pilothouse windows do not open. There are opening portholes in the staterooms and heads but not big enough for real ventilation. Now that the boat is in FL, the chiller system has been upgraded to 66K BTUs.
 
We have 2 units on board for heat and cooling. We love having A/C in the summer. What is nice about the PNW is that it can be 100f and by 10 PM it cools to the mid 50s.
 
My experience is we can hardly even use the flybridge in the summer .It does get warm a little at dock behind shelter but we just open the window. As long as there is cool water around the boat it seems our boat cant warm up.
 
Never had it and never needed it. I was a live aboard on a dark steel hull for years and never thought about it. The heat that the hull could soak in above the waterline was offset by the heat lost under the waterline. And I had opening portholes. That was back in the olden days with the hottest temp that I remember during the 1977 "heat wave" (96F).

My brother and I went out into the middle of Puget Sound and I dove over thinking that he could help me back on board (30 inch freeboard and no boarding ladder). He jumped in right after me. I was barely able to get a fingertip grip on the gunnel. I got out and helped him (he's shorter). Lesson learned.
 
I bought my boat on the east coast and brought it out to the PNW. It was built in the PNW, but for the east coast, so had two AC units. In the brief few days prepping the boat to come west, the AC was a life saver. Once here, I've used them on only two occasions that I can recall, in 4 years, and not really necessary then.

But: in the PNW humidity is the enemy. Running AC in the humid east, you get dehumidification for free. When I got the boat here, I removed one of the AC units and installed a "whole house" dehumidifier that blows throughout the boat using the existing AC ducting. It has been absolutely brilliant. Using only 400W when on, and running at a fairly low duty cycle, we keep it on a lot of the time, running from batteries even at anchor. Towels dry, nothing feels clammy, no mold, windows don't fog. It keeps the relative humidity at about 50-55%. Shut it off on a moist rainy day (and there have been a LOT of them this year) and humidity climbs into the mid 70% range, windows fog, towels don't dry, upholstery and bedding feels clammy.

If I was ordering a new boat for the PNW, it would absolutely have the AC ductwork installed, and a dehumidifier blowing through them.
 
We have it, and use it. :hide:
 
I have a lot of glass and my boat can heat up very quickly when the sun comes out. Despite this I have found that we could easily survive without a/c. There are two weeks in every year where we use the a/c. Why not, we have it and while we could survive with out it, it would be uncomfortable. Outside of those two weeks every year there just is no need.

Now that said, my boat came from L.A. and a/c was an absolute necessity there. My boat is very likely to wander down to Mexico so I am very happy to have the a/c for future use.
 
Our boat was sold new in Seattle but was built on the East coast, so of course it has 3 reverse cycle A/C units. The only time the A/C gets used is when the temperature hits 90 deg, which isn't that often here.
 
when making boat equipment decisions i always use the 80/20 or 90/10 rule. safety items not included.

in this case if i needed ac for 10% of the time i wouldn't get it and wouldn't size the gen for it. there is way too much maintenance for items that are only used 10 or 20% of the time.
 
We have 3 reverse cycle units.

Air Conditioning - They have been nice when the old dog got hot, and during the heat wave last summer. Once we were anchored at Rebecca Spit and it was in the 80s in the boat, so we used them. There have been times on the dock where we used AC as it was too noisy for open windows. We rarely visit marinas now. Need it, no. Useful and appreciated, yes.

Heating - We moved aboard in the fall and learned our Webasto hydronic system swills fuel. We began using the marine air for heat, and used it all winter. The boat remained free of excess moisture and we were comfortable.

I think there is a resale consideration here if you were considering this for a new boat.
 
A bit more about my boat. I was surprised to find that it is completely insulated between all the walls. I’ve never seen that before. Further, it has built in electric heaters in every living area. The chiller system mentioned earlier is also reverse cycle.
 
We live in the "Inland PNW", about 235 miles upstream from the coast. It's a desert climate and we have about 2 weeks of 100*+ temps in the summer. Our boat had 4 reverse cycle heat/air units and we used them a LOT.

It all depends on how far inland you are from the coast.
 
They sell standalone room air-conditioned now. Way less than a whole system, and way less mtx. A few hundred dollars for the good ones. I'd do that. No thru hulls, no pumps, no high power draw, and you can put it away in the winter.
 
I don't have/use AC in the San Francisco estuarian waters. In fact, kept the pilothouse doors often closed while underway. Can get hot in the inland delta, but the several times I've been there never missed absence of AC. (And I have low tolerance for high heat and humidity.) Anchored at flooded Mildred Island: https://en.wikipedia.org/wiki/Mildred_Island
 

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4 Units on board, one for all 4 cabins, one for the skylounge and two for salon/dining. We turn them all on for an hour every few months. That is the only use they have had. Main and upper decks have large sliding windows at sides and aft which provide good airflow, below deck is cooled by the proximity to our 55 degree summer water temp (PNW). ~A
 
I’m thinking I never used a/c in British Columbia north, except perhaps a few nights. There was that big heat wave a few years ago.

Is a/c now an essential to boating there given all the recent weather extremes or still an unnecessary one? East coast boats or maybe for Mexico but the PNW non Seattle?

Affects genset sizing too.

We put a self contained unit from Ocean Breeze in 2 seasons ago. There was a location above the pilothouse that was already plumbed for it with water hose already run and an extra thru hull was available in the engine room so made it an easier decision. It's a reverse cycle unit so we can use is as backup heat source if ever needed as well. We only installed register vents on the main level around the pilothouse and galley/salon area. No need in the staterooms below as it stays cooler being closer/under the waterline.

The past couple of years we have used it more and more with the number of 90+ days increasing. Some of that may be that we don't get the best airflow through the boat so even a day only in the 80s can really heat up the main area.

-tozz
 
The only time I have wanted it was one time when we were anchored close to shore in Desolation sound and the mosquitoes were really bad, so we didn't want to open the windows, and doors. Had a miserable night, then the next day dug out the bug screens that were stashed in a back corner, and life was much better. I could see it being nice if you spend a lot of time on the boat at the marina. My new boat came with air conditioning which we used in Hawaii. Haven't used it since I got the boat home to Anacortes, and don't expect to. I filled the raw water piping with RV antifreeze to keep it from freezing in the winter, or corroding. I would have to be pretty hot and miserable to use it as doing the antifreeze was a pain in the ass, and it's much easier just to leave it in there.
 
They sell standalone room air-conditioned now. Way less than a whole system, and way less mtx. A few hundred dollars for the good ones. I'd do that. No thru hulls, no pumps, no high power draw, and you can put it away in the winter.

I am thinking to get a couple of these when i start venturing south. not sure why not.
 
if nothing else, a stand alone would be a must if you are going to leave your boat unattended in a marina in the tropics for any length of time. Run it off shore power and keep the humidity down in the boat.
 

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