[C320-list] Air Conditioning Installation Question

Sat Oct 30 17:13:38 PDT 2010

Larry,

When we installed a 16.5k BTU reverse AC/Heat unit in the port locker we
made sure that a 5/8 inch layer of dense foam rubber was used to dampen the
unit's vibration so there was no direct transfer of vibration and noise from
the compressor by avoiding the unit's direct contact with the bottom of the
locker (that produced a sound box effect).  

We also added a 2 x 10 inch board beneath the unit raises the condensate pan
high enough to allow the condensate to drain directly to the transom exiting
in a separate line alongside the propane locker drain. To avoid any concern
about a backflow of water into the locker should we experience any heavy
following seas we also installed a seacock in the locker between the
condensate pan and the transom exit line.

We discoverer that it was more efficient to fashioned some quarter inch
plywood to develop a tight plenum box fit to the air return grill located at
the foot of the aft cabin. We sealed the box with some foam insulation tape
and also installed a grill in the aft cabin door that comes in handy to
quickly cool down the main cabin during those 90 degree /90 percent humidity
days when the aft cabin is not being used. The tight fit to the intake grill
reduces AC cycling.

Likewise we also mounted the pump in the aft cabin and insulated the pump
with some foam rubber to reduce pump noise and made sure that there was no
transfer of vibration to the aft cabin panels beneath the mattress. The cold
air exit is above the bread box and works fine, cooling the bow cabin with
no other air exits necessary.

One tip we did learn was to raise the lower limit on the auto-variable speed
unit fan because some marinas experience voltage drops. The lower fan
settings on the variable fans speeds tend to create armature heat when the
voltage drops and the windings begin to smell as the fan is turning too
slow. The fan may be damaged permanently if the variable fan speed lower
limits are not raised if the motor is heated repeatedly due to voltage
drops.

Only regret is that we did not get around to installing the unit earlier
after putting up with less desirable results from the portable 5K unit!

Rick

My-Ria #277

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Date: Sat, 30 Oct 2010 10:27:52 -0400

From: "Wash, Steve" <wash at advantageelectronics.com>

To: <C320-List at Catalina320.com>

Subject: Re: [C320-list] Air Conditioning Installation Question

Message-ID:

      <E7285F498EF9AB44AE20D9B340FA62398E170E at BACKUP004.Advantage.local>

Content-Type: text/plain;     charset="us-ascii"

Hi Larry,

I bought a piece of 'ACX' (Good one side, rough other side, exterior

glue) at Menards.  I think it was 5/8".  Painted it white and glued it in
the bottom of the locker with 5200 adhesive.  I did this because the unit
needs to be screwed down and there are a lot of wires and hoses running
under the locker and I didn't want to risk puncturing something.

I plan to use the remaining piece of the plywood to build a shelf over the
A/C unit to both recover the space and to make a better plenum for the air
return (it draws most of the air from the aft berth but some air is drawn
from the outside because the port locker doesn't have a tight

seal).   Our A/C unit had rubber feet that are supposed to reduce the

vibration.

We mounted the strainer and pump under the aft berth (I can send you
pictures if you like).  Another 320 owner in our marina (Michigan City), put
their pump under the galley sink.  Each has its advantages ... When it is
under the aft berth it was easy to run the water line aft and over to the
port locker.  We had the discharge water exit below the swim deck, aft.
When it is under the galley sink it is probably a little quieter.  You will
need to fish the water line under the stove area, the aft berth and then to
the port locker.  On that installation, they discharged the water out the
port side.  I will tell you that the pump is much quieter than the A/C unit.

You are going to hear the A/C run.  Everything is just too close.  The good
news is, of course, is that you will be much more comfortable at the end of
the day.  Ours has reverse cycle heating and it has been great at each end
of the sailing season.

BTW ... The most important tool to get for this job is a 'Step Drill'.

Look for it at www.mcmaster.com .  It is the only thing to use when making
holes in fiberglass and plastic.

We have the main discharge into the salon above the storage over the
refrigerator.  The air return is at the foot of the aft berth.  We have a
small discharge there, too.  That discharge is not ideal since some of the
discharge gets sucked back into the unit.  We just didn't want to run a hose
from there around the back to starboard side (head of the aft berth).  We
did not run a discharge to the V-berth.  The salon and v-berth are
comfortable without it.

It took 2 of us about 2 days to do the job.  There was a lot of thinking and
wondering time because we wanted to be careful not to put a hole in the
wrong place. Cutting the fiberglass for the grills was tedious and messy.
Don't rush this part because the fiberglass will chip.  I did a lot of the
cutting by hand because the sawsall was so rough.

I hope this helps.

Steve

Hull 1029

-----Original Message-----

From: c320-list-bounces at lists.catalina320.com

[mailto:c320-list-bounces at lists.catalina320.com] On Behalf Of Larry &
Melissa

Sent: Friday, October 29, 2010 12:28 PM

To: Catalina320.com

Subject: [C320-list] Air Conditioning Installation Question

Hi All,

I'm getting ready to install an A/C unit in Easy Going (not that we need it
now of course) and had a question or two for those of you who have your A/C
units installed in the port-side cockpit locker. How is the unit mounted?
Was there any kind of foundation built or wood mounting board installed or
was it just directly affixed to the locker floor? Was any stiffening added
to reduce fan/compressor vibration?

Also, where did you end up mounting your water pump?

Thanks in advance for any input.

Larry

Easy Going

Hull #609