Ice box insulation on Capri 26

[MORNING LIGHT 1]

On a Capri 26 1991 , what kind of insulation can I expect to find. Would like to improve insulation without taking the whole thing apart. Capri 26 were sold as daysailing boat but we often leave harbour for 3 days or more and once for 16 days on the Lake Ontario and a good icebox would be welcome. Can not think about a refer unit without this step first. Any suggestion ? Thanks in advance !

[tuomas]

Hi, no experience on capri but some general experiences and operations: i suspected that the icebox in my elan 40 was poorly insulated. Compressor ran 90% of the time and meat got bad in two days. Blue hull did not help. Since the cabinet structure was some kind of screwed-from-inside-glued -the-desk i got a cheap usb camera with a long gooseneck and drilles some holes. Whohaa, lots of empty space and very poorly installed insulations. Got some single componen PU foam and installed extra hose and nozzle to the bottles (two componen from eg soudal would form closed cells and would thus be better but you can explode the bottle if you do not empty it in due time..) extra hose brings a considerable extra friction in the ouflow which causes bad leaks - i put the bottles
in a plastic bag and let the foam leak into thebag, most of it went out nicely. Watched foam flow with the cam. Flexible foam is more controllable as it expands less. Note that youcan break cabinets by overfilling with the foam! Prepare for lots and lots of foam everywhere and cover all the surfaces near the operation point. I used 8 bottles and some of them leaked badly . Well the outcome was a success, running time went down to some 30% and temperature fell to proper readings. Will add some insulation behind the asu unit to the inside to get insulation even better. Really a good job, though very laborious and dirty.

[MORNING LIGHT 1]

Thanks Tuomas for sharing your experience . Can I get the P.u. foam that you bought in a regular hardware store or is this marine specified. You can buy some expandable foam to fill around any door about anywhere but I 'm just not sure we are talking about the same product.

[tuomas]

Sorry for a little bit messy earlier reply, I typed it with a phone while putting a child to sleep..

I ran through the options when I did the job, and ended up with this solution because I could not disassemble the cabinet. If you can open the cabinet where the icebox is, I definitively propose you use solid polyurethane insulation board (what is the English for this... fixed stuff that you use to insulate the house). This board is made of two-component polyurethane and contains closed cells, thus offering much better lambda and less hassle when installing. As the heat conductivity is critical especially if spaces are confined, do NOT choose anything cheaper, like styrofoam - difference in heat conductivity is 100%.

Some 50 mm (2 inches) of solid PU is enough - the more the better. Finalize the work with sprayable PU, (yes, the stuff you get from hardware stores. Select the type that will stay flexible as this type usually expands much less and is less hazardous to the structures. ) Be very careful with corners and seams.

Check also that there is no air leaks in the box (e.g. drainage hole in the bottom and an open hole where the pipes of the evaporator come through in the top + cold = constant pumping of warm air through the box..)

If you must spray PU into the structures, prepare for a MESS. Do cover all the surfaces and have lots of acetone and cloths available. Cover the laptop you need with the camera with a plastic bag (preferably transparent. Use good rubber gloves to avoid using acetone to your hands. Try to use as large extra hoses as possible in the PU bottles and fix them very carefully. Pistol type PU dispatcher is much better than the bottles. remember to clean the dispatcher and the hoses carefully with a cleaning liquid before any breaks. Remeber that the cleaning agent contains acetone - have acetone compliant extra hoses or remove hoses from the pistol when PU is still wet.

Do not try to fill the cavities with one spraying. Spray first one third of the volume (have an assistant to use the flexible camera), let it expand and the next day spray another third etc. It may also be wise to spray some water in to accelerate the fixing of the foam.

Remember that the propellant in the PU bottles is usually a mixture of propane and butane (with no odorant) and thus HIGHLY FLAMMABLE. In confined spaces like the boat you can in principle reach the lower explosive limit. Hence, disconnect the batteries before the operation. Also organize good ventilation as propane and butane can displace oxygen and make you feel dizzy.

Hope this helps

[MORNING LIGHT 1]

Thanks again for all the details cause just like you, I do not have access to the icebox since it is in one piece, I 'm gonna have to go with spray. But I didn't think it would make such a mess ! I' ll be prepared ! One thing tough, what is exactly P.U. . Is it the same stuff we use to seal when installing a new door in the house on an outside wall or is it something different? Thanks again !!

[tuomas]

Yes it is. Among these products, select one that is promised to stay flexible when cured.