Sunday, October 11, 2015

A little Air Please!

Our first trip on our first boat, JD - 2005 Catalina 250 Water Ballast, was a melt down! It was the first week in July in Biscayne Bay, and it was hot! After one night on the boat, we decided to install Air Conditioning.

And now we are there again but this time on Eximius, we learnt that requirement during the Shake Down Cruise

Maybe I'm not handling the heat so well or maybe it's just hotter and more humid, but any work inside the boat and, well, you would be hoping I'm using a good deodorant.

So time to start installing Air Conditioning on Eximius. It's not rocket science, goes something like this:

Install the AC unit:

  • Install a shelf to sit the AC unit (that's going to be under the V-Berth so as not to use up any valuable storage area)
  • Mount the new AC unit on the shelf and clamp it in place.


  • Put a two new Thru Hulls and shut off valves for the AC Supply & Discharge water (they'res going to be under the V-berth too)
  • Install the new new AC water pump in the V-Berth, it has to be below the water line.
  • Connect a hose from the Supply Shut off valve to the Pump via a sea strainer
  • Connect a hose from the AC Discharge to the Shut off valve on the Discharge Thru Hull (above the waterline)

Electrical Installation:

  • Connect the AC unit electrical control box on a bulkhead under the v-berth
  • Connect 110v from the AC Aux circuit breaker in the Electrical Distribution panel to the AC unit electrical control box
  • Install the AC digital control panel at the Nav station
  • Connect the AC digital control panel to the AC unit electrical box

Ducts & Return Installation:

  • Manufacture a Teak Box to go on the V-Berth Stbd hanging locker top with vents into the V-Berth and through the Main cabin bulkhead - they will provide air to the V-berth and stbd side of the cabin.
  • Connect Duct T to AC unit
  • Connect Flexible Duct from one side of the T on Stbd side to a box on the top of the hanging locker
  • Connect Flexible Duct from other side of the T on Port side to another T in the area beneath the V-Berth draw unit.
  • Manufacture a Teak Box to go on the V-Berth Port Draw unit top with vents into the V-Berth and through the Main cabin bulkhead - they will provide air to the V-berth and port side of the cabin.
  • Connect Flexible Duct from the T below the draw unit up to the box on the draw unit top.
  • Connect Flexible Duct from the T below the draw unit aft behind the bench back storage shelves, behind the Nav station, behind the head (inside the head storage lockers) and then over to a vent in the Quarter cabin.
Phew! I find that on bigger projects, it's best to write out a plan, then, on site, walk through the process to figure any gotcha's. It also helps to identify which tools are needed, supplies and fittings etc.

We'll have to haul the boat out to install the new Thru Hull for the AC water Supply, but as we need to replace the Depth/Speed/Temp transducer, we'll be able to do that at the same time.

I'll update this post with Pics of the Process.

October 11th.

Step1. Clean out the V-Berth Storage and mark up the location of the shelf support beams.

I had measured up the beam dimensions and cut them out of ply at home this morning.

After scribing, glue them (one of the rare times I'm open to using 3M 5200 adhesive.

Need to let the glue cure for 24 hours.

Pretty pleased with progress today. (Sunday Oct 11th.)

I plan on going down to the boat mid week to make the shelf template.

Monday October 12th.

Quick visit to the boat tonight, I took several sheets of cardboard to make a template of the shelf. The 3M 5200 had cured and the support beams were firmly in place. In reality, the weight of the AC unit will be spread around the edges of the shelf so the point loading on the beams will be minor. I will glass them into the sides of the hull as well as glass the shelf to the hull and the beams. This is one of those 'do it once, it'll last forever, so do it right' things.

I emailed Dometic yesterday asking about the pump size, I was a bit concerned that the pump I purchased might be too big. They confirmed, I need to move down a size from the 3CP to the 2CP, it's about the same price. I went back to West Marine to return the pump and ordered the correct one. While at WM, I picked up the materials to glass in the shelf.

Possible Change in plans
After discussing my project with several other owners, the plan to pull the boat could be  off the table. Originally I had intended to T the AC Supply (input) into the Head Supply hose and save having to cut another Thru Hull in the boat (and save having to haul the boat to do so)

Other owners consensus is that it's ok to T into the head hose.

So I'm going to see if I can run a straight line from the head cupboard to the V-Berth. If successful, then take that route, if not, stay the current course and plan to haul the boat.

Marked up the ply using the template, ready to cut that and paint the surfaces with Resin.

We're hoping the weather forecast improves so that we can take the boat out this weekend, if it does, we'll relax, if not, I'll get more of the AC install done.

Slight Mod. Someone suggested that I put Anti Vibration matting beneath the AC unit, sounds (no pun intended) like a good idea, but the shelf position is to high to allow that. So I removed the support beams and glassed the shelf directly to the hull (just had to slide it down and aft a bit, fit very like a glove)

After 24 hours, the GFP had set and my neighbor helped bring the AC unit onto the boat, I really didn't want to slip or trip while carrying the unit.

The AC unit is set on the shelf with a 1/2" Anti Vibration rubber mat to help keep the noise down when the unit is running and we're asleep just a few inches above it.

The fan outlet is pointing aft and the raw water supply and discharge ports can be seen to the left of the fan assembly.

Setting it in place gave me a good idea about the location of the ports, the electrical panel and where the ducting will connect. It also indicated that the discharge port (top left) needs a port side thru hull.

The AC unit's return air grill is on the port side.

There's about a 2" gap between the top of the AC unit and the underside of the V-Berth mattress support. I hope to install some marine sound proofing material on the underside of the mattress support. My experience with Dometic AC units has been really good, it's the FAN that makes the noise or rather the sound of the air pumping through the duct work. But I'm hoping the Anti Vibration mat beneath the unit and sound proofing above it will keep noise to a minimum.

We also purchased a Honda EU2000i Companion Gas Generator to power the AC when we're on the hook. I'll have to make a support for the generator so that it can be mounted outside the Cockpit to keep any CO from being an issue. Then a second support to keep the generator in the aft locker when we're underway.

If we ever have to have the AC unit serviced, I'm hoping that having comparatively easy access to the gas ports that are on the top front end of the unit will make service easier.

Next step is to make the Thru-Hull and connect the electrics.

1st the Electrics:
The AC Electrical unit is separate from the Main AC unit.

Easy to install: Cut a piece of ply and rounded the edges. Sanded it and a coat of resin all over.

Glued it to the hull with some 5200

Screwed the box to the ply after connecting the 110v wiring.

The 15' cable from the Electrical box to the AC control unit was too short, but it's a standard CAT 5 cable, so a trip to lowes for a 25' cable. (max length according to the manual that came with the AC unit is 30')

A few minutes with my multi tool and I had cut a hole in the face of the instrument panel at the Nav station and installed the control unit. I'll connect the electrics to the boat's electric distribution panel tomorrow and run the new CAT 5 cable to the control unit. That will complete the AC unit electrics.

I should get the Thru-Hull completed tomorrow too.

Ok, didn't get to the Thru-Hull, need to make a backing plate at home first.

But I did get the electronics box wired up.

The white wire is the 110v supply to the AC unit

The grey wire is a Cat 5 Cable from the AC Unit's electronics box to the AC Control/Display unit.

Nice and neat. gotta love tie-wraps

That's the AC Electronics box complete.

The 110V has to be connected to the Electrical Distribution panel, and I have to research that project.

The Panel has a 110V block of circuit breakers, some are 15Amps and the rest are 38Amps.

The 'Aux' breaker has a wire on it right now, but I don't know where it goes, have to find that. But it's also just a 15amp breaker and I think the AC needs to be on a larger breaker.

The ply panel that the electronics box is mounted is glued to the hull with 3M5200 marine glue. that should hold a lifetime.

Here's where the 110V has to connect in.

Can you spell nightmare? The wiring monkeys were smoking when they put that together.

Ordered a 25Amp Circuit Breaker & a spare 15Amp for whenever.

Going to be fun wiring up to the new Breaker.

Still going: (November 1st 2015)
Over the weekend, I managed to get the raw water hose run from the Head locker to the V-Berth, connected up the Pump to the hose and to the A/C unit.
The challenge was to get the hose run with minimal bends in the hose and a flow generally upwards from the Thru-Hull.
I used a fiberglass bendy rod to fish beneath the cabin floor under the Nav table, shower pan and into the locker in the head where the Thru-Hull is located, that was pretty straight forward, but you know it took a lot of tries to get the rod where I could reach it in the head cupboard.

Next was to run the hose beneath the holding tank forwards into the v-berth. I used a flashlight and a mirror to view under the tank from the only area where it's visible. My concern here was having to drill through the bulkhead between the holding tank locker and the locker forward of it, there's a heavy duty fiberglass partition between them. Drilling was only possible from the forward locker, which meant the tip of the drill bit would be out of sight when it broke through the partition, and my fear was that it might penetrate the holding tank, that would be a real mess!
After careful measurement, I figured I had 3 inches of space so using a short hole saw I would be safe. Phew!
Cutting through the two remaining partitions on either side of the V-berth 3 drawer cabinet was easy. Then I used the rod to pass a line through each stage of the hose install and got the hose easily into the v-berth. This was one of the toughest parts of the install so far. I had tried several different routes for that hose, and finding one that worked was a big relief.

Making progress.

Left to do:
.. Mount the pump on it's new shelf (make the shelf)
.. Connect the raw water strainer before the pump.
.. Hook up the pump to the electronics box.
.. Secure the A/C unit to it's base shelf (easy)
.. Hook up the electronics to the Boat's AC power
.. Install the A/C discharge Thru-Hull
.. Install the condensate drain.
.. Turn the A/C on - just so that we know it works - no duct's in place yet, so can only run it a short while to prevent it freezing up.
.. Install Duct into v-berth hanging locker
.. Build the duct in the v-berth that will house the A/C vent
.. Cut holes into the Main Cabin from the v-berth for the A/C vents that will be above the cabin table settee
.. Turn it on (just a short while, no duct installed yet)

We'll see how much of that gets done tomorrow, we're really looking forwards to our next trip away from the dock, it could be anywhere, even lunch at a dockside restaurant!

Update: 11/4/2015
We spent a couple of hours on the boat today, installed the Water Strainer (Pump mounting shelf not ready yet) Then hit a snag, the tube of sealant I had intended to use to seal the Thru-Hull was useless! That's the second tube... Better go buy some new tubes.

I did get a couple of little projects done, but not related to the A/C. Looks like this weekend I'm going to focus on that.

Update 11/8/2015

Finally managed to install the A/C discharge thru-hull, after I went to WM to get a 2nd new one as I cut the first one too short! Grrrr.

That brown goop around the thru-hull flange is epoxy resin with a brown filler. Makes it easy to check that the filler is evenly spread around.

It's really awkward to get into that area, but it's installed, right, and very firmly attached to the hull. That's not going to go anywhere!

That completes the water lines to and from the A/C unit.

Next I installed the new 25amp circuit breaker and connected the power to the Electronics Box, the lamp says it all - we have power!

But sometimes things don't go right. I had assumed that the RJ45 Ribbon cable was a standard straight through connection, but when I hooked up the A/C control panel at the Nav Station, it was totally dead, not a glimmer of power or control.

Looking at the ends of the supplied connector, I could see that it's not quite a standard Cat 5 Cable, the ends are swapped, so Pin 1 goes to Pin 8 on the other end.

I used the old, short, cable and the A/C flashed up for the first time and was blowing COOOOL air!

So I need to makeup new ends for the Cable and then it's time to start on the Duct work. I'll head down to the boat on Tuesday night to make the cable and cut the first duct hole.

I was able to cool the boat from 87 F down to 79 F, that's going to make working on stuff inside the cabin a whole lot more comfortable.

Stay tuned, I hope to complete this project this coming weekend.

Almost there! Peggy & I worked on the A/C system this weekend. All the ductwork is in place, cable is replaced and working, built the wooden duct from the Stbd locker top to the Cabin and V-berth grills.

Last part is to make the return grill beneath the V-berth and varnish the wooden duct on the Stbd locker.

Hope to get these done so that we can take the boat out on Saturday.

So, varnish the new woodwork, put all of the cushions and covers back in their normal location, and make the interior of the boat look nice for visitors.

I'll post a bunch of pics on completion.

Stay tuned.

No comments:

Post a Comment

Got questions or suggestions about our boat, our sailing or our adventures?
Leave a comment.