AC on a Golden Wave 42

[chas.sail]

Just moved back home from SAn Fran Bay to Charleston. I liveaboard now. I will have to install a AC system in my Golden Wave 42. Any other owners who have installed? Any recommendations on unit and positioning. I check his forum every day and love it. Thanks in advance for any advice

- Dan on SV Deseado

[btrayfors]

Originally Posted by chas.sail

Just moved back home from SAn Fran Bay to Charleston. I liveaboard now. I will have to install a AC system in my Golden Wave 42. Any other owners who have installed? Any recommendations on unit and positioning. I check his forum every day and love it. Thanks in advance for any advice

- Dan on SV Deseado

Hi, Dan...

I assume by "AC" you mean air conditioning, not alternating current!

I have owned and cruised a GW42 for the past 25 years. About 10 years ago, returning from a long stint in the Eastern Caribbean, I installed A/C on my boat.

My boat is kept much of the year in Washington DC where:

1. the summers are brutal.....temps up near 100F for days; and
2. the winters can be equally brutal....temps down near zero F and windy for days on end.

Although I have an Espar diesel heater, I wanted an A/C system which could deal with the cold as well as the heat. The reverse-cycle A/Cs (like the popular CruisAirs) can't do that so well when the water temp gets much below 40F as it often does here.

So, I did some research and settled on the Flagship A/C self-contained units because they were well built, had first-class accessory components, and used a big 2,000 watt electric coil system for heating instead of the more common reverse cycle (no moving parts, not affected by water temperature).

I've been happy with this choice. Aside from a few little glitches, my two units have been very reliable and can easily cool my boat in summer and heat it in winter.

I chose a 16,500BTU A/C for installation under the master berth in the aft cabin, and a 12,000BTU unit for installation under the port V-berth in the forward cabin.

In moderate conditions, just one of these is capable of heating or cooling the whole boat. Two are required only in extreme conditions.

Here's a pic of the larger (16,500BTU) unit installed under the aft berth.



Hope this helps.

Bill

[Cowboy Sailer]

How will you power the AC? What size generator on board?

[btrayfors]

Originally Posted by Cowboy Sailer

How will you power the AC? What size generator on board?

Not sure what the OP plans to do.

I have a 3.5KW NextGen generator on board which can easily power either A/C, but labors with both. You'd really need a 5KW genset to power both.

Of course, at dockside I use shore power.

It's very important to distribute the load. For example, you can't really run both A/C units from one 30A 120VAC line, partly because of compressor startup needs but mostly because 30A lines and connectors really can't handle 30A continuous at all.

The typical 30A connectors are horribly designed and should never be loaded more than about 23-24A continuous, and even then they need to be really clean and well maintained.

A 50A circuit would be much better for handling both A/Cs. Or, you could put one A/C on each of two 30A lines, providing that other heavy loads were controlled (hot water heater, microwave, toaster, hair dryer, big battery charger, etc.).

Bill

[rourkeh]

I have a Cheoy Lee 44' that I am just finishing a total refit on. I added two 16,500 btu A/C units to the boat some time ago, one under the forward V berth on a custom platform, and I built a space for the second when I removed the pilot berth for installation of the washer/dryer.
Most small marine A/C units, (non chilled water systems) are a piece of crap that use cheap materials and fancy circuit boards (expensive). They fail constantly and require you to purchase expensive replacement parts to keep a badly designed product working. If you want to save yourself a lot of grief talk to the guys at Flagship Marine in Florida Marine Air Conditioning Systems - water, air and keel cooled. . All they do is build high quality marine air-conditioning systems that cost the same or less than marineair or others and are WAY better quality. Also some of the best customer service I have seen in a long time.

[redsky49]

Originally Posted by btrayfors

Hi, Dan...
So, I did some research and settled on the Flagship A/C self-contained units because they were well built, had first-class accessory components, and used a big 2,000 watt electric coil system for heating instead of the more common reverse cycle (no moving parts, not affected by water temperature)....

I chose a 16,500BTU A/C for installation under the master berth in the aft cabin, and a 12,000BTU unit for installation under the port V-berth in the forward cabin.

In moderate conditions, just one of these is capable of heating or cooling the whole boat. Two are required only in extreme conditions.

Here's a pic of the larger (16,500BTU) unit installed under the aft berth.

Attachment 102745

Hope this helps.

Bill

A couple observations, based on my professional experience, of this particular installation:

The discharge plenum, placed directly at the fan outlet, will adversely affect supply air performance. As a general guideline, about 5 duct diameters (minimum) should be straight duct prior to any changes in duct direction. This is especially true after the fan discharge. Even placed at 5 feet downstream, the plenum is too small and poorly constructed for proper airflow. Coupled with the near 180 degree turn of the flex duct results in a severe negative impact on airflow. The poor layout of the ductwork will result in extreme turbulence, noise and reduced airflow. This is not a good example of a proper ductwork installation. And you should always allow the airflow to straighten out before introducing another elbow or turn. Two turns in quick succession is markedly worse than the sums of their individual impacts.

The return air path is also restricted due to the face of the evaporator coil (at the back of the unit in this picture) being placed so close to the bulkhead. Blocking the return air path is similar to blocking the suction side of a pump. This is far more of an impact than blocking the discharge side. I would say that this example is probably the minimum acceptable free area for the return air path. Be aware that basic maintenance will require that the face of the evaporator be vacuumed or, if using a removable filter, be accessed. The more space the better. It could be that the pic reduces the apparent clearances.

At moderate conditions, a heat pump in reverse cycle heating, will produce 2.5 to 3 times the heat of an electric resistance heater. Bill is correct that heat pump efficiency drops rapidly once the water temperature approaches the 30's. But if the water temp is that cold, the air temp is also quite likely very cold. In that case, the modest 2kw integral heater is not going to be adequate to heat most boats. It will also be more expensive to operate than a heat pump if you are at a metered electrical connection.

All retrofits will be compromises. The more efficient installations will keep these compromises to the minimum, and will result in a more satisfactory experience. In general, minimize the use of flex duct and pull it tight to minimize the corrugated effect of the wire reinforcement. Provide a return air grille at least a size larger than recommended [Based on the actual free area of the grille, airflow should be in the 250-400 fpm range]. A 45 degree duct turn is better than a 90 degree turn. Allow adequate service space. Provide means of dissipating the compressor heat - vent the cabinet.

A lot of people seem to complain about the performance of their AC units. I think much of this stems from the installation.

Other than that, it looks nice

[btrayfors]

Redsky49,

...other than that, Mrs. Lincoln, how did you like the play?

Seriously, I appreciate your observations, but I think you have a couple of misconceptions.

1. The air return is at the forward side, not the rear side near the bulkhead. And, there's a big grill and filter in front for air intake. Also, there's more room in the rear than appears in the photo.

2. Your comments re: bends in the ducting are well taken. However, everything's a compromise. I had a professional VAC friend take a look, and he advised me how best to handle the ducting and plenum. Since the photo was taken, I had a special plenum fabricated which reduces, but doesn't quite eliminate most of the bends. Also added an additional 4" duct.

3. In practice, the air conditioning unit works very well and has done so for several very hot seasons. The forward A/C also works extremely well, and doesn't have the bendy ducting problems of the aft unit.

4. The single 2K watt coil has been VERY effective in keeping the whole boat at reasonable temperatures, except in extremely cold weather when I use the Espar for additional heating. And, I don't have to worry about pumps or water temperature or....anything at all.

Nothing's perfect, of course, but this installation does work and works very well for my needs.

Your comments do underscore, however, the desirability of engaging a knowledgeable VAC expert when planning an A/C installation, hopefully to find workable solutions to some of the most knotty problems.

Bill

[GordMay]

Greetings and welcome aboard the CF, Dan.

[chas.sail]

Originally Posted by chas.sail

Just moved back home from SAn Fran Bay to Charleston. I liveaboard now. I will have to install a AC system in my Golden Wave 42. Any other owners who have installed? Any recommendations on unit and positioning. I check his forum every day and love it. Thanks in advance for any advice

- Dan on SV Deseado

Sorry - Yes Air Conditioning

[chas.sail]

Right now looking at shore power. Will look into generator later. I see the upcoming threads may suggest a generator

[redsky49]

Originally Posted by btrayfors

Redsky49,

...other than that, Mrs. Lincoln, how did you like the play?

Seriously, I appreciate your observations, but I think you have a couple of misconceptions.

1. The air return is at the forward side, not the rear side near the bulkhead. And, there's a big grill and filter in front for air intake. Also, there's more room in the rear than appears in the photo....

Your comments do underscore, however, the desirability of engaging a knowledgeable VAC expert when planning an A/C installation, hopefully to find workable solutions to some of the most knotty problems.
Bill

I try not to be critical but sometimes can't help myself. Criticizing someone's boat seems akin to criticizing someone's wife. Done only with extreme caution and never received well

However, to clarify one issue for others who might read this thread:

The return (or entering) air does most likely enter at the back of the evaporator coil on your unit. The supply air fan is connected to the "leaving" side of the evaporator coil. If you look at the back side of your unit with a mirror you should see something very similar to the pic below. This is the area where typically a coarse filter element is installed and which you would vacuum or clean on a regular basis. I have marked airflow with red arrow on the pic.

This is where too often the unit is installed too close to a solid surface and the airflow is restricted, impacting performance.

Flagship Marine (and/or Ocean Breeze) seem like one of the better values in marine HVAC. I have a difficult time seeing where the thousand (or more) dollars being asked for brands such as CruiseAir is justified unless this is the advertising costs, plus more expansive parts and dealer network.

Glad to hear you revised the discharge plenum. Another area where efficiencies can be found is the seawater (or condenser water) flow. More flow generally equates to better heat transfer. Don't undersize the seawater hose sizes and/or pump.

Stay cool. I am quite familiar with summers on the bay. Cheers!