Installing refrigeration and insulation

[Sven]

We just brought the Cape Horn wind vane and the Frigoboat refrigeration units down to Senta to start both those installations ASAP. We just about finished the windlass installation and only have cosmetics left to do, some are not insignificant: http://www.grenander.com/Senta_II/B...rise_when_replacing_forward_cleat_(Sven).html

When doing the new refrigeration and insulation I think I have it pretty well thought out, but I'd still like a sanity check.

We'll be adding 2" - 4" of insulation on the sides of the ice box compartment (Home Depot pink, non absorbing closed cell). We'll probably add up to 6" facing the outside of the hull and also 6" on the bottom.

I have two main questions about the installation that I'd like any second opinions about.

First, I've been considering placing a sink-type trap in the bottom of the box. In other words, a pipe that goes down and then curves up before going back down again. The idea is that it would hold some amount of condensation water in the trap so that cooled air would not flow out of the fridge through the hole to the bilge but at the same time it would allow the box to be rinsed out from time to time, or just defrosted. Would we be better off just putting in a simple straight drain with a drain plug ?

The second question has to do with sequencing the work. Right now I'm thinking we'll do all the insulation and internal box work first. After that we'd cut the holes and route the compressor tubes etc.. Is there any reason to reverse the order and pull the tubes and wired first and then build the insulation around them ?

Ok, I'm cheating ... I have a third question. I'm planning on lining the inside of the box with epoxy sealed plywood which is glued in place against the insulation and then glassing the interior corners for a water proof seal. If the cut pieces are sealed with Smith's Penetrating Epoxy and not cut or trimmed after that, is there any reason to use marine grade plywood ?

As usual ... thanks.



-Sven

 

[PDX]

On the first question, I've seen solutions as apparently simple as finding the right diameter of cork to stuff in the drain. But the gurus say to leave the drain out (of a refrigerator) as too problematic to be worth the effort after you've gone to the trouble of carefully fitting together four inches of insulation.

On the second question, I think you have to fit the insulation in first.

On the third question, what are you trying to accomplish with the plywood? Why not just epoxy the insulation, and then fair and paint it if you're concerned about appearance?


BTW, the best step-by-step routine I've come across for building a refrigeration box is from Don Casey's updated "This Old Boat." Especially the section on designing and crafting the lid.

 

[Sven]

On the third question, what are you trying to accomplish with the plywood? Why not just epoxy the insulation, and then fair and paint it if you're concerned about appearance?

I think (but would be very happy to be told I'm wrong) that the epoxy will melt the insulation. Otherwise just glassing the inside would indeed be a great solution. The inside surface does one way or another have to be smooth enough to be hygienic. The plywood could be contact cemented to the insulation and then sealed in the corners.

Thanks !



-Sven

 

[Loren Beach]

I think (but would be very happy to be told I'm wrong) that the epoxy will melt the insulation. Otherwise just glassing the inside would indeed be a great solution. The inside surface does one way or another have to be smooth enough to be hygienic. The plywood could be contact cemented to the insulation and then sealed in the corners.

Thanks !
-Sven

I have always understood that epoxy would not dissolve the foam, while poly resin would.

Anyone else recall?

LB

 

[exoduse35]

From all I have read it is probably best to remove the old insulation as it is likely to be moisture laden and not very effective anymore. Also it seems that wrapping it in a couple layers of foil in the insulation has a beneficial effect. I too am starting this project and am not looking forward to the insulating part. I have wondered about using the expanding 2 part foam they sell at TAP PLASTICS to get behind the box against the hull and below the box. So while I am commenting, has anyone done this and is that product suitable for the project? Edd

 

[PDX]

Although I have not yet expoxied over extruded polystyrene (the pink Home Depot stuff you're using) I would not hesitate to do so, because I've expoxied over both medium density closed cell Airex and also over the expanding foam that comes in a bottle (which I believe is open celled). I had no problems with either one. In my experience polyester resin will dissolve these materials (as Loren states).

 

[PDX]

From all I have read it is probably best to remove the old insulation as it is likely to be moisture laden and not very effective anymore. Also it seems that wrapping it in a couple layers of foil in the insulation has a beneficial effect. I too am starting this project and am not looking forward to the insulating part. I have wondered about using the expanding 2 part foam they sell at TAP PLASTICS to get behind the box against the hull and below the box. So while I am commenting, has anyone done this and is that product suitable for the project? Edd

That is the way the ice box on my boat was done at the factory. If you have any stanchion or deck leaks behind it, the foam will soak it up. Once this happens (as happened with my boat) it loses its insulating capacity. I think you are better off starting with an oversized box and then filling it with insulation, then glassing the insulation. You can glass the outside of the box and then run a limber hole on the end on the downhill side. This should eliminate any potential water intrusion.

 

[Rick]

I am in a process of insulating my Icebox in E-32 .My boat is in Isla Mujeres,Mexico, and after two days of using my Icebox ,old insulation was dripping water from condensation. I am removing my old insulation, to do that I remove bulkhead in lazaret and a wall in eng. compartment [close to the sink] After two days of work my Icebox is clean on 4 sides. On the fore side of Icebox I leave old insulation, witch will be encase in new two-part urethane foam, and that will seal old foam. You can see some pictures on work in progress.

 

[Tom Metzger]

I think (but would be very happy to be told I'm wrong) that the epoxy will melt the insulation. Otherwise just glassing the inside would indeed be a great solution. The inside surface does one way or another have to be smooth enough to be hygienic. The plywood could be contact cemented to the insulation and then sealed in the corners.

Thanks !-Sven

I put the Home Depot foam into some of the spaces between the webs in the triaxial force grid to eliminate standing water. There was no problem glassing it with West epoxy. I wasn't looking for beauty, BTW.

 

[Rick]

Work in progres

Today I made a retainer box of Styrofoam ,and fill in with 2 part high density foam.To separate foam from a hull I use heavy plastic witch also give you protection from moisture.

 

[Sven]

Today I made a retainer box of Styrofoam ,and fill in with 2 part high density foam.To separate foam from a hull I use heavy plastic witch also give you protection from moisture.

That's a great idea, to use foam as the outside box.



-Sven

 

[Rick]

Work in progres

Filling foam insulation is done.I did pore 2 part foam in stages, to control volume, and watch for heating-up. After incasing Icebox in Styrofoam I fill hull cavity thru opening I made in galley cabinet