In my CD 36 (1982, hull #76), I've noticed that there is something like two or three inches from the inside of the refer box to the outside of the cabinetry. Does anyone know if this space is filled with insulation? If so, what kind? in the interests of improving efficiency, would it be worth drilling holes and injecting additional foam insulation into these spaces?
Regards,
-- David
jdr@compuserve.com
Refer insulation
Moderator: Jim Walsh
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Matt Cawthorne
Re: Refer insulation
David,
I am in the process of finishing up the trim on a job in which I removed the old icebox and refrigeration system and put in a new, heavily insulated deep freeze/frige combination in my CD-36. Since my hull number is #79 you can assume that the icebox insulation is the same. It looks as though the entire galley was assembled outside of the boat and bonded in prior to installation of the deck. I believe that it is for this reason that there is a gap underneath the box and to the outside. The entire icebox was made with 1 inch of insulation between two layers of fiberglass. In addition there is an extra inch of foam on two sides (between the icebox and the engine compartment and between the icebox and the stove). The top of the box had one inch of unprotected foam in some areas and no insulation in others. In addition there is the R value of the plywood. The lid has no insulation that I could tell, but I never ripped it apart to see.
If you are going to spray foam insulation into these areas here is some information for you. Be careful that the foam insulation does not expand and crush the box.
1. There looked to be an inch or two of gap between the back of the box and the bulkhead which forms the front of the port cockpit locker. Access here would be straight forward. Just drill small holes in the bulhkead and spray through. cover the holes when done unless you are certain that the foam you are using is at least fire retardent.
2. The bottom is the hardest area to get access to. There was 1 or two inches of gap in here. one way to get access is to put an extension on your foam nozzle and spray it in by going in under the sink, under the stove and then under the icebox. There is probably no way to know how to guide the foam in to be certain that you did a good job of filling this area in. Nor could you tell when you were done how much area you had covered. Another way might be to drill through the cockpit locker bulkhead right near the bottom and fill it from there. That area is hard to work in unless you are much smaller than I am. Again, you will have no way of knowing what area you were covering. A third access for part of it would be to remove the engine compartment insulation and feed a tube in through the large cutouts that were put in to clear the engine mount and the icebox drain hose. The third option might just be the easiest.....believe it or not.
3. There is a cavernous area outboard of the iceobx. If you were to drill through the bottom of the corner cabinet you could dump a great deal of foam in there. You could also put it in through the bottom of the cabinet behind the stove.
4. The top. You could glue pieces of EXTRUDED (not expanded) styrofoam to the top of the inside of the box.
I think that adding foam would help, but don't be fooled into thinking that this extra foam is going to improve the insulation enough to cut your heat loss by a factor of two. The foam coverage will be too spotty and most types of foam absorb water over time. When they do the R-value drops in half.
Good Luck.
Matt
mcawthor@bellatlantic.net
I am in the process of finishing up the trim on a job in which I removed the old icebox and refrigeration system and put in a new, heavily insulated deep freeze/frige combination in my CD-36. Since my hull number is #79 you can assume that the icebox insulation is the same. It looks as though the entire galley was assembled outside of the boat and bonded in prior to installation of the deck. I believe that it is for this reason that there is a gap underneath the box and to the outside. The entire icebox was made with 1 inch of insulation between two layers of fiberglass. In addition there is an extra inch of foam on two sides (between the icebox and the engine compartment and between the icebox and the stove). The top of the box had one inch of unprotected foam in some areas and no insulation in others. In addition there is the R value of the plywood. The lid has no insulation that I could tell, but I never ripped it apart to see.
If you are going to spray foam insulation into these areas here is some information for you. Be careful that the foam insulation does not expand and crush the box.
1. There looked to be an inch or two of gap between the back of the box and the bulkhead which forms the front of the port cockpit locker. Access here would be straight forward. Just drill small holes in the bulhkead and spray through. cover the holes when done unless you are certain that the foam you are using is at least fire retardent.
2. The bottom is the hardest area to get access to. There was 1 or two inches of gap in here. one way to get access is to put an extension on your foam nozzle and spray it in by going in under the sink, under the stove and then under the icebox. There is probably no way to know how to guide the foam in to be certain that you did a good job of filling this area in. Nor could you tell when you were done how much area you had covered. Another way might be to drill through the cockpit locker bulkhead right near the bottom and fill it from there. That area is hard to work in unless you are much smaller than I am. Again, you will have no way of knowing what area you were covering. A third access for part of it would be to remove the engine compartment insulation and feed a tube in through the large cutouts that were put in to clear the engine mount and the icebox drain hose. The third option might just be the easiest.....believe it or not.
3. There is a cavernous area outboard of the iceobx. If you were to drill through the bottom of the corner cabinet you could dump a great deal of foam in there. You could also put it in through the bottom of the cabinet behind the stove.
4. The top. You could glue pieces of EXTRUDED (not expanded) styrofoam to the top of the inside of the box.
I think that adding foam would help, but don't be fooled into thinking that this extra foam is going to improve the insulation enough to cut your heat loss by a factor of two. The foam coverage will be too spotty and most types of foam absorb water over time. When they do the R-value drops in half.
Good Luck.
Matt
mcawthor@bellatlantic.net
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Jeff Barnes
Re: Refer insulation
Matt:
I am curious to know what system you are installing. Jazman (CD-36 #68) is due for refrigeration next spring. SeaFrost (electric) is one I am considering.
Regards,
Jeff
I am curious to know what system you are installing. Jazman (CD-36 #68) is due for refrigeration next spring. SeaFrost (electric) is one I am considering.
Regards,
Jeff
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matt cawthorne
Refrigeration system.
Jeff,
Before you go and buy a refrigeration system read up on the theory a bit. You will find that Coefficient of Performance (COP) is the measure of how much heat energy the system can remove from the box as compared to how much electrical energy it uses. If it can remove a kWh of heat for 1/2 a kWh of electricity the COP=2.0. What determines what the COP is? Mostly the refrigerant, the temperature of the icebox and the temperature of the condenser. What you will find is that the greater the difference between the temperature of the evaporator and the temperature of the condensor the more current that it takes to remove a BTU. My old unit was an Aldor Barbour Cold Machine. It was (and is if anyone wants it) a very reliable machine. Unfortuneately it is a unit that sat in the port cockpit locker which is basically the same temperature as the engine compartment when the engine is hot and as hot as the deck when the sun is out. Therefore the system was moving heat from the evaporator up to probably 140F. That is a delta (when using the system as a frige) of about 102 degrees on a hot day. Now imagine if it could dump that heat to the 80F water instead. The difference in temperature of only 52 degrees. That can almost double your efficiency. That guided me to a choice of water cooled units, although with a blower fan, some ducting and a few extra holes in the boat an air cooled unit might have been a reasonable second choice. My next thought was that I hate plumbing and hate having to drill another hole in the bottom to attach another rubber hose and hate having to drill another hole to exhaust the water. The unit that I chose was an Itailian unit made by Frigoboat. The condensor is a dynaplate mounted on the outside of the hull with only the refrigerant running in and out of the boat. Yes, it was another hole in the boat, but at least the thing going through it was a piece of bronze with a big backing plate and a big nut on it. No water hoses, just refrigerant. As long as the dynaplate does not disolve completely the only way water can get in is to have the dynaplate mostly disolve and the water come in through the small refrigerant lines. I like the system. When I went shopping for it the only importer in the US was Simpson-Lawrence. They were merging with Lewmar and seemed to be useless at ordering what I needed. They were of no help. Through their web site I found the Canadian importer and bought one from them. I bought the K35 compressor a flat evaporator and a keel cooler. ( since then an outfit in Annapolis, Md has become the importer and they are very helpful, knowledgeable and can get the unit at a lower price. Their number is 410-268-2123).
I cut a hole in the bottom of the dry locker next to the sink. There is a nice big spot under there to install the compressor. I then put a removable bottom in the locker so that it can be serviced. I put the keel cooler through the hull just about a foot forward of the sink, just outboard of the fuel tank. The lines are really well protected there. The next thing that I did was to install the evaporator and thermostat. I tested it and it seemed to work fine. I put the top on the icebox, put a new laminate over the screws and re-installed the cabinetry. After that I found out that the thermostat was not working correctly. The unit keeps the deep freezer at around 5 degrees Farenheit on it's warmest setting. That is fine except that it is using a lot of current to do that. (I think around 40 amp hours on a hot day) My whole reason for doing the job was to have refrigeration without having to run the engine every day. I chartered a boat with engine driven refrigeration once and felt like I was a slave to it. This 40 amp hours was going to force me to run it every third day. Still not good enough. I called the folks in Annapolis and they told me how to make an adjustment inside of the thermostat to change the temperature range over which the thermostat works. I will go down to the boat this weekend, make the adjustments and see what the current usage is. It is supposed to be a hot one so I hope to get a good test. I hope between the lower amount of heat going through the walls and the better COP that I can get the usage down to around 25 AH. That will give me 5 days between engine runs. With a solar panel and/or wind and/or water generator perhaps the engine will only be used rarely to charge batteries.....We shall see. I figure that If the system is used only as a refrigerator, not for freezing, that I might be able to get the current consumption down to around 15 AH......We shall see.
In general I am very happy with the Frigoboat system. It is quiet, small, and seems to do the job very nicely. Now that there is a helpful service operation I heartily recommend the system.
Note that my new iceobx installation has 5 inches of foam on the thinnest side, up to 7 inches elsewhere and a few very expensive R-50 vacuum panels in strategic locations. With the original icebox you could never expect to see such low current consumption. One CD-36 owner commented to me that to keep his icebox cool his system had to run 24 hours a day in the summer. I never had the guts to let my old system run that much so I never found out how long it had to run to keep the box cold.
Give me a few months to shake the system down and I will give you an update. I took lots of pictures of the job as it was happening, but there has not been time in my life to find a scanner (or to develop most of them). I hope to be able to share them with any interested CD-ers by mid-summer. I still want to finish the trim before I take the 'finished' picture. For now it is sailing season and I am going sailing.
Matt
mcawthor@bellatlantic.net
Before you go and buy a refrigeration system read up on the theory a bit. You will find that Coefficient of Performance (COP) is the measure of how much heat energy the system can remove from the box as compared to how much electrical energy it uses. If it can remove a kWh of heat for 1/2 a kWh of electricity the COP=2.0. What determines what the COP is? Mostly the refrigerant, the temperature of the icebox and the temperature of the condenser. What you will find is that the greater the difference between the temperature of the evaporator and the temperature of the condensor the more current that it takes to remove a BTU. My old unit was an Aldor Barbour Cold Machine. It was (and is if anyone wants it) a very reliable machine. Unfortuneately it is a unit that sat in the port cockpit locker which is basically the same temperature as the engine compartment when the engine is hot and as hot as the deck when the sun is out. Therefore the system was moving heat from the evaporator up to probably 140F. That is a delta (when using the system as a frige) of about 102 degrees on a hot day. Now imagine if it could dump that heat to the 80F water instead. The difference in temperature of only 52 degrees. That can almost double your efficiency. That guided me to a choice of water cooled units, although with a blower fan, some ducting and a few extra holes in the boat an air cooled unit might have been a reasonable second choice. My next thought was that I hate plumbing and hate having to drill another hole in the bottom to attach another rubber hose and hate having to drill another hole to exhaust the water. The unit that I chose was an Itailian unit made by Frigoboat. The condensor is a dynaplate mounted on the outside of the hull with only the refrigerant running in and out of the boat. Yes, it was another hole in the boat, but at least the thing going through it was a piece of bronze with a big backing plate and a big nut on it. No water hoses, just refrigerant. As long as the dynaplate does not disolve completely the only way water can get in is to have the dynaplate mostly disolve and the water come in through the small refrigerant lines. I like the system. When I went shopping for it the only importer in the US was Simpson-Lawrence. They were merging with Lewmar and seemed to be useless at ordering what I needed. They were of no help. Through their web site I found the Canadian importer and bought one from them. I bought the K35 compressor a flat evaporator and a keel cooler. ( since then an outfit in Annapolis, Md has become the importer and they are very helpful, knowledgeable and can get the unit at a lower price. Their number is 410-268-2123).
I cut a hole in the bottom of the dry locker next to the sink. There is a nice big spot under there to install the compressor. I then put a removable bottom in the locker so that it can be serviced. I put the keel cooler through the hull just about a foot forward of the sink, just outboard of the fuel tank. The lines are really well protected there. The next thing that I did was to install the evaporator and thermostat. I tested it and it seemed to work fine. I put the top on the icebox, put a new laminate over the screws and re-installed the cabinetry. After that I found out that the thermostat was not working correctly. The unit keeps the deep freezer at around 5 degrees Farenheit on it's warmest setting. That is fine except that it is using a lot of current to do that. (I think around 40 amp hours on a hot day) My whole reason for doing the job was to have refrigeration without having to run the engine every day. I chartered a boat with engine driven refrigeration once and felt like I was a slave to it. This 40 amp hours was going to force me to run it every third day. Still not good enough. I called the folks in Annapolis and they told me how to make an adjustment inside of the thermostat to change the temperature range over which the thermostat works. I will go down to the boat this weekend, make the adjustments and see what the current usage is. It is supposed to be a hot one so I hope to get a good test. I hope between the lower amount of heat going through the walls and the better COP that I can get the usage down to around 25 AH. That will give me 5 days between engine runs. With a solar panel and/or wind and/or water generator perhaps the engine will only be used rarely to charge batteries.....We shall see. I figure that If the system is used only as a refrigerator, not for freezing, that I might be able to get the current consumption down to around 15 AH......We shall see.
In general I am very happy with the Frigoboat system. It is quiet, small, and seems to do the job very nicely. Now that there is a helpful service operation I heartily recommend the system.
Note that my new iceobx installation has 5 inches of foam on the thinnest side, up to 7 inches elsewhere and a few very expensive R-50 vacuum panels in strategic locations. With the original icebox you could never expect to see such low current consumption. One CD-36 owner commented to me that to keep his icebox cool his system had to run 24 hours a day in the summer. I never had the guts to let my old system run that much so I never found out how long it had to run to keep the box cold.
Give me a few months to shake the system down and I will give you an update. I took lots of pictures of the job as it was happening, but there has not been time in my life to find a scanner (or to develop most of them). I hope to be able to share them with any interested CD-ers by mid-summer. I still want to finish the trim before I take the 'finished' picture. For now it is sailing season and I am going sailing.
Matt
mcawthor@bellatlantic.net