420DB – Bridge A/C and Heat Installation

[fwebster]

So when do we get to vote on where to drill the hole in the side of your boat for the discharge hose?

What would really be cool, save a lot of the line loss and allow all the A/C system to be more efficient would be to build an oversized trunk line (like 2") into the boat where no pressure was needed to expel the cooling water from the compressor coils. He'd have one large thru hull replacing all the small ones.

 

[Alex F]

So when do we get to vote on where to drill the hole in the side of your boat for the discharge hose?

I break my projects in phases:
Phase 1. Analyses and design.
Phase 2. Product purchase.
Phase 3. Installation.
Phase 4. Testing.

Drilling holes is part of the installation, so its coming soon. :grin:

Alex,

I wouldn't read much into the fact the the 560DB has only a 16K bridge air unit. Bridge and cockpit a/c is a relatively new "must have". Prior to the mid 2000's it seems only the bigger boats had them and the size of the units were only what would fit within the standard generator capacity. Later models have more energy efficient electrical components so there is more "room" in the generator capacity for bridge/cockpit air. Sea Ray did/does offer enough bridge or cockpit air to hang meat, if you order the boat with an optional up-sized generator and that, plus the added cost of the A/C units and plumbing was way more than any dealer would order on an inventory boat.

Got it. Thanks Frank.

I own a boat, optimism is no longer in my vocabulary.

I guess you should have gone for the bridge boat....LOL

 

[Turtlesboat]

What would really be cool, save a lot of the line loss and allow all the A/C system to be more efficient would be to build an oversized trunk line (like 2") into the boat where no pressure was needed to expel the cooling water from the compressor coils. He'd have one large thru hull replacing all the small ones.

that's what I have on my boat. 2" discharge line that both AC units feed. Zero pee noise and reduced pressure.

 

[Greg]

What would really be cool, save a lot of the line loss and allow all the A/C system to be more efficient would be to build an oversized trunk line (like 2") into the boat where no pressure was needed to expel the cooling water from the compressor coils. He'd have one large thru hull replacing all the small ones.

That's an interesting thought. Could you run the discharge close to the other discharges and tee them together into one bigger thru-hull?

Although in some ways it's nice to be able to 'see' the discharge from each unit. This will also be important initially with the single pump setup to ensure adequate flow.

 

[Alex F]

....Although in some ways it's nice to be able to 'see' the discharge from each unit. This will also be important initially with the single pump setup to ensure adequate flow.

For these reasons, and of course due to the fact that a discharge line thru hull is above the water level so it's not a big deal, I'll install a dedicated one next to the existing thru hulls on the stbd side.

 

[Hampton]

Mine is near the rear of the boat. Just catching up on this thread.

 

[Hampton]

Once primed, won't the higher elevation unit require the same head pressure as the lower units? (I believe that is why the tech used the term "Farthest" unit (line length and therefore loss of flow) rather than "Highest" unit). On my boat, the worst one is the master stateroom A/C unit because the through hull for the outflow is at the highest elevation of the three. It's just like a siphon once primed, right? The issue may be getting it to prime - granted. But, the flow should be equal to the others. I don't claim to be an expert, just brainstorming. Bash me for that, though. It's fun!

Alex,

Are you placing the unit in the side storage unit next to the Captain's seat in the bridge? Obviously, you need to consider the space available up there when considering the 24K BTU system. Breathing air space, ducting, physical size/shape. I'm sure you've looked into this, but, there's a lot to think about when going larger than the SR system. Just trying to help.

 

[Alex F]

Thanks for your input, John.

Yes, the unit will go in the stbd side storage box. There's enough room, but the doors opening might be a really tight squeeze.

The reason I'm looking to go with Ocean Breeze unit 22,000BTU is b/c based on the specs I'm getting much more on the output for a small price of extra 3.5amp load. I know I was talking about the 24K for a while but after looking closer the 22K is much more reasonable approach. 24K btu unit draws 20amps while 22K draws 14.5amps. IMO, the difference of 3.5amps is very reasonable, while jump of an extra 10amps is too aggressive.

I'm still at the beginning stage of learning the best approach for the ducts and vents location and installation. Based on the pix from OB site for the installation kit I don't like their round vents and will be discussing my options for replacement of those that can rotate, adjust the angle and close.

 

[Hampton]

My return air inlet is on the front of the storage unit. There is a plenum at the back of the unit with a medium sized, square vent facing aft toward the table. The other air line goes into the wall and forward to the helm. Under the helm, there is another plenum which splits off to two vents. One is on the starboard side and one the port. The port one is medium-small, round, and rotates (my addition). The starboard one is very large and square. It is canted to blow on the Captain's face : )

 

[Alex F]

John, would you mind snapping few pictures of your installation (vents location, thermostat location and how they covered the unit inside the box)? I assume that they installed some kind of wall with quick access to the unit's filter?

 

[Hampton]

Sure. Later today. Covered which box? The control unit at the helm?

 

[Alex F]

Much appreciated, John.

The box I was referring to is the stbd side storage box where the main A/C unit is installed. I'm thinking that there should be some room left for a small storage area and the A/C unit is covered by some white board with quick access. Is your like that or is it completely exposed when the doors are open?

 

[Greg]

Once primed, won't the higher elevation unit require the same head pressure as the lower units? (I believe that is why the tech used the term "Farthest" unit (line length and therefore loss of flow) rather than "Highest" unit). On my boat, the worst one is the master stateroom A/C unit because the through hull for the outflow is at the highest elevation of the three. It's just like a siphon once primed, right? The issue may be getting it to prime - granted. But, the flow should be equal to the others. I don't claim to be an expert, just brainstorming. Bash me for that, though. It's fun...

Yes. Provided the outlet is down low (which it will be)
That's why he may not even need the flow restricting valves.

 

[Hampton]

Oh, that one. It's wide open in there, just like the one under the bed. Is that what you mean? I just open the doors and reach in to access the screen filter. I'll get a pic of that too anyway.

 

[beachcombersc]

May want to double check that the trigger box can have both 120v, and 240v triggers added depending on which AC unit you choose.

 

[Hampton]

 

[Alex F]

Thanks, John! That's exactly what I was looking for.

The pic of the unit in the storage box shows that there's not much space left. I thought there would be some extra room left. I guess due to the other vent on the side of the box facing aft they had to move the unit to utilize most of the box space.

The round vent by the stbd side seat, I understand that you can rotate it to adjust the direction of the air coming out of it, but does it allow to close it completely (let's say a/c is on for too long and admiral gets cold and wants that vent closed)?

Very nice dinghy. I remember your thread on it, but don't recall seeing the final result of your search or construction of this dink.

 

[Hampton]

The round dohicky in the middle actuates flapper valves visible down inside to close off the round port side vent.

 

[Lady Ashley SR560]

The only time I use the AC on the bridge is while underway in very hot bad weather. In light to moderate rain I always like the glass rolled up for better visibility. If its really pouring its down and the AC is on. I close the hatch atop the stairs and its very comfortable .I really never entertain people up there unless I'm underway then I open everything any way. On rare occasions at the dock if I'm working on something up top I will turn it on. Again it's not super cold but it very comfortable even on a very humid day.

 

[Alex F]

As I'm getting closer to the purchase of the package I thought that having a some sort of diagram will help me get an overall view of the components involved. I don't have special software to do professional looking diagram, so I'm using the tools I have and an image from user manual. It's kind of quick and dirty, but it still gives a good idea of what's involved.

If you guys see something that doesn't make any sense, please feel free to comment.

The first draft of the diagram: