500/520 DB official thread

Wonder why they went with stowaway units on the bridge of the 52 vs the split systems from the factory on the 480DB. Perhaps just due to lack of space on the 480DB bridge?
 
Wonder why they went with stowaway units on the bridge of the 52 vs the split systems from the factory on the 480DB. Perhaps just due to lack of space on the 480DB bridge?
I do know that the split systems are both more expensive to procure and more expensive to install; there is another complete separate operation after installation to pump down and charge the loop which must be done during manuf. Space in total is greater for a split system but allows it to be distributed so space required on the bridge (for example) is much less. Also, split systems can be obtained in significantly larger BTU ratings. What I don't know is if multiple air handlers can be installed with a single condenser....
 
Can one of you guys that added valves to your AC raw water distribution manifold take a picture and post here, please. I've thought of doing that but haven't figured out exactly what valves to use to prevent a significant reduction in water flow during normal operation. Thanks.
Not valves but these nylon hose connections -
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I do know that the split systems are both more expensive to procure and more expensive to install; there is another complete separate operation after installation to pump down and charge the loop which must be done during manuf. Space in total is greater for a split system but allows it to be distributed so space required on the bridge (for example) is much less. Also, split systems can be obtained in significantly larger BTU ratings. What I don't know is if multiple air handlers can be installed with a single condenser....
I just got off the phone with our local marine AC guy and he is recommending a split system around 4 tons (48,000 BTU) with dual air handlers on the bridge. The big issue he sees is getting the copper lines with insulation up to the bridge. He also said that the system will be much quieter....
 
No kidding - I pulled a fiber optic and HDMI cable over to the television and thought I'd never get them through the tubes and corners....

I also ran a cable from under the helm around to the Radio Remote under the TV. May have been the hardest wire I have ever had to fish and I had a great helper. After installing the new remote I realized that is a terrible spot for it. We would bump it and turn the volume way up. So I removed the remote and blanked it off.

Should have just put the wire in a wire loom and ran it under the bench seats.

Maybe I will find another use for the N2K wire over there...
 
I also ran a cable from under the helm around to the Radio Remote under the TV. May have been the hardest wire I have ever had to fish and I had a great helper. After installing the new remote I realized that is a terrible spot for it. We would bump it and turn the volume way up. So I removed the remote and blanked it off.

Should have just put the wire in a wire loom and ran it under the bench seats.

Maybe I will find another use for the N2K wire over there...
Oh yea - I did the NMEA 2000 wire also for the Fusion remote there.

So if we put an air handler in that sink cabinet the seating will need to come out so the copper tubing can route and be secured back in that impossible area.
 
I removed the clarion remote didn’t see a need for another remote so I installed a 4 position USB outlet wired to the 110v outlet in the cabinet. no Idea why the pic is gigantic....
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I just got off the phone with our local marine AC guy and he is recommending a split system around 4 tons (48,000 BTU) with dual air handlers on the bridge. The big issue he sees is getting the copper lines with insulation up to the bridge. He also said that the system will be much quieter....

I've spent quite a bit of time on 520s and 480s bridges, and the first time I saw that SR made a switch from split (on 480s) to self contained unit, I was very surprised.

Those are obviously pros and cons with both applications. If I was to do the installation from scratch, I'd seriously consider doing split system. However, considering that you have 27K unit already installed, a split system add-on sounds like an overkill. Self contained is much simpler to install and maintain.

Since you own the boat you can judge better, but as I recall, existing unit is tucked well under the helm and is not too loud. So, when choosing additional unit, location and size is very important. I would focus on finding good location where the new unit can be tucked away to minimize the noise.
 
I've spent quite a bit of time on 520s and 480s bridges, and the first time I saw that SR made a switch from split (on 480s) to self contained unit, I was very surprised.
Those are obviously pros and cons with both applications. If I was to do the installation from scratch, I'd seriously consider doing split system. However, considering that you have 27K unit already installed, a split system add-on sounds like an overkill. Self contained is much simpler to install and maintain.
Since you own the boat you can judge better, but as I recall, existing unit is tucked well under the helm and is not too loud. So, when choosing additional unit, location and size is very important. I would focus on finding good location where the new unit can be tucked away to minimize the noise.

Actually, I'd get rid of the existing unit under the helm and install all new 48K BTU split system with two air handlers; one under the helm (where the existing is) and one under the bar. The original unit under the helm was a 24K BTU then about five years ago replaced with a Dometic DCU 27K BTU and is actually pretty loud even though not that old.
Maintenance will be much easier and simpler with the split system as the raw water loop is completely contained in the engine room as that is where the condenser unit will be located. Access under that side of the helm will be better as the air handler is a fraction of the size of the current unit. The most difficult aspect of a split system is routing the copper tubing from the engine room to the bridge but I've been in every nook and cranny and think it can be done.
 
Just a side note you may want to consider..., We have two units for the main deck, two 24,000 BTU units. Both units run off a common raw water supply line, simple inline "T" diverts water flow to two units. From individual units the discharge is two separate lines.
 
Actually, I'd get rid of the existing unit under the helm and install all new 48K BTU split system with two air handlers; one under the helm (where the existing is) and one under the bar. The original unit under the helm was a 24K BTU then about five years ago replaced with a Dometic DCU 27K BTU and is actually pretty loud even though not that old.
Maintenance will be much easier and simpler with the split system as the raw water loop is completely contained in the engine room as that is where the condenser unit will be located. Access under that side of the helm will be better as the air handler is a fraction of the size of the current unit. The most difficult aspect of a split system is routing the copper tubing from the engine room to the bridge but I've been in every nook and cranny and think it can be done.

If you consider the option of removing the existing unit, then I would agree that replacing it with split system will get you desired results. If you plan on keeping the boat for a while, it would be worth the investment, IMO.

BTW, now I see why you have 27K instead of 24K. As far as I recall, 500/520DBs came with 24K unit.
 
We are closing soon on a 52 Sedan Bridge. I'm going to order some new dock lines. Any advice on how big the eye splice needs to be?
 
We are closing soon on a 52 Sedan Bridge. I'm going to order some new dock lines. Any advice on how big the eye splice needs to be?

Congrats that's pretty exciting. We have 12" Eye Splices in our 3/4" Lines and they work well. Which year is the 52 DB that you are buying?
 
Thanks. I think I've read every article/posting on the QSM11. Quite a bit of info out there!

And the interesting thing is SBMAR.com (Tony) now acknowledges that he doesn’t know the cure to the leaking exhausts. After years of chaising this issue it seems many folks have trimmed props and redone their manifold gaskets without long term success.

Tony sometimes will suggest that Owners are not removing enough pitch to fix the issue.
 
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This is probably a stupid question relating to prop pitch, but do the props need to match? My port exhaust is 900 degrees religiously. My starboard is 1100 if I am under 2000rpms. Can I just adjust the starboard more?
 

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