Visit our Popular Forums

OzeLouie · 17-10-2021, 22:20

How did you go Captain?
Were you able to locate the mystery leak?

DeBe · 18-10-2021, 05:00

Best way to find very small leaks is use soapy solution. Leak detectors are not mutch good. Also have used epoxy to repair leaks in aluminum pipes & evaporators successfuly for years.

Richard Kollmann · 18-10-2021, 08:12

To re index the electric snifter turn it on in another clean air area. The area in and around box can be cleaned free of refrigerant vapor using a vacuum cleaner. Refrigerants are heaver than air so removing air below leak improves meter sensitivity. Leaks in high pressure side are easer to find with compressor running. The leak detector will get you close to leak area but may not pinpoint the actual leak, soap/water generated foam will.

Captain Bill · 18-10-2021, 11:16

Now for an update. The news is not good I'm afraid. In going over the freezer side with the sniffer the only place that went off was at the base of the putty which was sealing the entrance hole where the capillary tube and suction line entered the freezer compartment. On the outside of that hole is foam insulation covering both the line entrance to the freezer at the bottom and the refrigerator section at the top. This is foam pipe insulation sealed with more putty. I cut the putty and stuck the sniffer under the edge of the pipe insulation and it screamed so I knew the leak was somewhere in that area. I split and removed the pipe insulation and at first the sniffer screamed no matter where I put it as the area must have been saturated. After letting it sit a day the only place it still triggered as in the hole going to the refrigerator. The insulation is about two inches thick and the only place it triggered was at the very bottom of the hole where the evaporator supply line and suction line pass through the interior wall of the refrigerator. I guess the term bottom may be misleading as this is a horizontal hole. It's really hard to get soapy water into the hole but It appears that I have a slow leak in the supply line, but because of where it's at I can't be absolutely sure as the tubes are almost in contact and the bubbles are coming out between them. Basically the leak is inaccessible without removing the refrigerator evaporator. The supply line bends 90 degrees downwards essentially immediately and is soldered to the freezer evaporator suction tube which I would have to cut to remove it. That would be the smallest problem I would have to deal with. The suction line is the problem. In their effort to get the most efficiency out of the unit the ran the capillary tube through the suction line of the refrigerator evaporator for about 15 inches. Unfortunately it emerges from the suction line in the middle of the bend in where it exits the refrigerator side. I cannot remove the refrigerator evaporator without cutting the capillary tube which is part of the freezer evaporator. Trying to patch the capillary tube after cutting it is way above my silver soldering skill level. I asked Nova Kool if there was a procedure for doing this repair on Friday and they have not responded. It looks to me like the most obvious solution is to replace both evaporators and resolder everything. I'm figuring by the time you add parts and labor to that we are probably getting close to price of a new unit.

As far as I know there are only two units which will fit into the cabinet, the Nova Kool 7501 and the Isotherm Cruise 200. The Nova Kool is quoting 3 to 6 months for delivery. I guess the supply chain problem has got them. I've also bee a bit disappointed on how well the Nova Kool handled temperatures in the tropics. The BD35 compressor and a front loading unit had a pretty hard time in the tropics. The Isotherm has a BD50 and might do a bit better in the heat. I added more solar a few years ago so I'm not nearly as concerned about power consumption as I used to be. Several outlets claim to have Cruise 200s in stock on their web sites though the two I've called have failed to return my calls to confirm that fact.

Also the tap was a red herring, it's not leaking.

pyrrano · 18-10-2021, 13:48

If I understand correctly, your line set (cap tube + suction line) is leaking as it penetrates into the box? In that case just cut both a few inches from the evaporator, cut them again on the outside of the box and use couplings and new piping for whatever you cut out. You won't need to run the cap tube through the suction line as long as you tape them together and insulate them. You'll need 15% silver to braze (I assume everything is copper) and most likely acy/oxy torch but if the suction line is smaller than 3/8" you might be able to do it with yellow map gas torch.
Vent the gas out before you start working and drop in a new charge after the work is done and vacuumed the system for an hour.
Manufacturer can tell you what size (ID) cap tube you'll need and you can use pinched 1/8" couplings to make the connections.
This would be a good time to reinsulate the suction line with 1/2-3/4" wall armaflex.

Captain Bill · 18-10-2021, 15:27

More bad news I'm afraid. I got the drawings for the Cruise 200 and it will not fit. Also the Nova Kool is apparently made out of unobtainium. Dealers and distributors are reporting 6 month plus delivery times. One is still waiting on units ordered in May. I thought about rebuilding the cabinet, but I can really only expand it about 1.5 inches and because of the different flange design I can need about three inches to make the Cruise 200 fit. I was talking to Sure Marine and when I started to tell him where it leaked he finished telling me exactly where. Design flaw? He had definitely seen it before and confirmed that the cost of repair would exceed the cost of a new unit. He also told me that some customers have had some luck patching the leak by turning the unit on its side and filling the hole around the lines with JB weld until they could get a replacement unit. Anyone have any thoughts on that?

It's been about 45 years since I've done any silver soldering. I have a Mapp torch but no acetylene. There are probably a couple of feet of extra capillary tubing next to the dryer so I could probably cut out the capillary tube running inside the suction line if I thought I could resolder the capillary tube without filling it with solder. I'd probably see if I could find some capillary tubing and some couplers and practice a bunch before I did the real thing. I'm getting a quote on a new refrigerator side evaporator. I'll let people know how it goes.

OzeLouie · 19-10-2021, 02:55

That is bad luck Bill, but it is unfortunately as I had suggested posts 4 &7. The problem now is to decide what is the best way forward. I would suggest replacing the entire fridge if you can as any repair of a system that has leaked refrigerant from the low side and now most likely contaminated, is problematic at best and as you were advised, could be very costly.

One repair possibility would be to discard and replace the existing evaporator(s), along with the suction line and capillary. Have the repaired system extensively evacuated using a two stage vac pump and have a 052 filter dryer added before re-gassing. If replacing with aluminium evaporators, be sure to check that the aluminium suction line is air sealed especially where it joins to the copper or bundy tubing. (as I described in post 7)

Cheers Ozelouie

Richard Kollmann · 19-10-2021, 06:55

Captain Bill,
It is unlikely you will find a different unit that will replace the present two compartment refrigerator freezer two door box. I agree the only problem with the old one was lack of BD35 compressor capacity in the tropical climates. Nova Kool may offer a compensated price on a new like unit but with a BD50 compressor. It is a shame you were lead down the primrose path convincing you to invest in vacuum pump, leak detector and servicing equipment.

Captain Bill · 19-10-2021, 07:23

Quote:

Originally Posted by Richard Kollmann

Captain Bill,
It is unlikely you will find a different unit that will replace the present two compartment refrigerator freezer two door box. I agree the only problem with the old one was lack of BD35 compressor capacity in the tropical climates. Nova Kool may offer a compensated price on a new like unit but with a BD50 compressor. It is a shame you were lead down the primrose path convincing you to invest in vacuum pump, leak detector and servicing equipment.

Actually I have been contemplating buying that equipment for some time now so that's not a big deal, well at least the gauge set and leak detector which I can use on my nearly antique cars. It's almost too bad someone doesn't do a re-manufacturing service on these things. The case is still fine. I'm clearly not a refrigeration engineer, but as I understand it replacing a bd35 with a BD50 is not a simple swap out of the compressor, but involve a different size condenser, capillary tube and evaporators. If it was just a refrigerator or I could buy a DIY kit from Adler Barbour or Isotherm and just use the old case, but they don't offer a two zone solution as far as I can tell.

OzeLouie · 19-10-2021, 15:50

Quote:

Originally Posted by OzeLouie

That is bad luck Bill, but it is unfortunately as I had suggested posts 4 &7. The problem now is to decide what is the best way forward. I would suggest replacing the entire fridge if you can as any repair of a system that has leaked refrigerant from the low side and now most likely contaminated, is problematic at best and as you were advised, could be very costly.

One repair possibility would be to discard and replace the existing evaporator(s), along with the suction line and capillary. Have the repaired system extensively evacuated using a two stage vac pump and have a 052 filter dryer added before re-gassing. If replacing with aluminium evaporators, be sure to check that the aluminium suction line is air sealed especially where it joins to the copper or bundy tubing. (as I described in post 7)

Cheers Ozelouie

The evaporators with capillary and suction line attached are listed as 'spare parts' by the maker. (Evaporator 75R and evaporator 75F)
Have you checked availability and price to evaluate if viable to repair?

Captain Bill · 19-10-2021, 16:59

Quote:

Originally Posted by OzeLouie

The evaporators with capillary and suction line attached are listed as 'spare parts' by the maker. (Evaporator 75R and evaporator 75F)
Have you checked availability and price to evaluate if viable to repair?

They said I could order them through Sure Marine Services. I talked to them Monday and they were going to get me a price. I have not heard back from them yet.

SemperAvanti41 · 22-10-2021, 08:10

Have you considered an Isotherm 2010-SX or similar? I have successfully used one in one of my two freezers and have another that I need to install.

Captain Bill · 23-10-2021, 05:44

Problem solved. New Isotherm 200. I'm going to have to do some cabinet modifications as the case is slightly deeper than the Nova Kool. Since the Cruise 200 has an BD50 instead of a BD35 it should do a bit better than the Nova Kool here in Florida. The build quality of the Isotherm seems a bit better than the Nova Kool and the hardware a bit heavier duty. It did cost a couple of hundred more than what a Nova Kool would have cost but considering the the bigger compressor and heavier duty hardware it's probably worth it. Once I got the dimensioned drawings I found I only actually need 1.375 inches and was within my 1.5 inch limit so It will work out.

I am disappointed to tell you that when I informed Nova Kool of where the problem was located and asked if there was a procedure for repairing/replacing the failed part they stopped responding to me, whereas before that they were quite helpful. I wish they would have at least responded that there was no practical way to repair fix the problem instead of ghosting me.