Freezer burn

[PMF1984]

My freezer has gone out. Well not completely, but 30 isn't cold ehough.

I have a Isotherm C195 unit, so its a fridge/freezer combo. Taking it out and sending to the shop means no refrigeration till it comes back. Not really an option as I live on the boat.

I was told we can't go north ( planned for 3 weeks from now) unless we have a freezer.

Is there an easy fix here?

I thought that I could buy a small "portable" freezer and sell it once I'm north and moved back to dry land.

open to suggestions

 

[Comodave]

We replaced the refer in our boat last summer with an Isotherm unit. It works great. We also carry a chest freezer that is about 100 quarts. It lets us carried a lot of frozen food. I just bought a small power pack to power the chest freezer while we are underway so we don’t have to run the genset. It should power the freezer for about 4 hours on a charge.

 

[Mambo42]

My freezer has gone out. Well not completely, but 30 isn't cold ehough.

I have a Isotherm C195 unit, so its a fridge/freezer combo. Taking it out and sending to the shop means no refrigeration till it comes back. Not really an option as I live on the boat.


Is there an easy fix here?


open to suggestions

I googled your fridge / freezer and understand it has 1 compressor ? Is that correct ?
There are a couple of very easy checks, which you can do yourself.
I read it is fan cooled and your problem usually results from the ventilator failing. They pick up dust, gets into the bearing and ultimately the fan will fail. When the fan fails the compressor becomes too hot and the fridge will switch itself off on the high pressure safety. Result is that it won't be able to supply enough cooling energy (you cannot cool down the compressed liquid) and the result is that the freezer will stop functioning.
So before you ship it out, remove it from its location, plug it in and first check if the compressor switches on or not.
If the compressor switches on then check if the fan is still working. If the fan does not work, buy a new one and install it. 99 % chance the system will work again.
If the fan is running however then check the evaporator. If that is covered in dust the high pressure liquid can also not be cooled and the fridge / freezer won't function properly.
If that is also not the case i fear the problem is worse, then you may have lost gas and that is possible if the fridge has been switched off for a prolonged period of time.
In the old days the pipes in the fridges and freezers were made of copper, which would not deteriorate. in modern fridges / freezers they changed the copper for aluminum, which is much cheaper. Only problem is that Aluminum becomes poreus if the fridge / freezer sits idle for a prolonged period of time. Then the gas escapes and it cannot be repaired.
An easy way to check whether you lost gas is to switch the system on. The top part of the compressor should become warm / hot. If it stays cold or a bit warm you have lost gas.

Hope you will be able to find out which one it is ?

 

[PMF1984]

We replaced the refer in our boat last summer with an Isotherm unit. It works great. We also carry a chest freezer that is about 100 quarts. It lets us carried a lot of frozen food. I just bought a small power pack to power the chest freezer while we are underway so we don’t have to run the genset. It should power the freezer for about 4 hours on a charge.

Dave, that looks like a solution. I have a 1000 watt inverter that I can use while underway to run the unit, then plug in at night.

 

[PMF1984]

I googled your fridge / freezer and understand it has 1 compressor ? Is that correct ?
There are a couple of very easy checks, which you can do yourself.
I read it is fan cooled and your problem usually results from the ventilator failing. They pick up dust, gets into the bearing and ultimately the fan will fail. When the fan fails the compressor becomes too hot and the fridge will switch itself off on the high pressure safety. Result is that it won't be able to supply enough cooling energy (you cannot cool down the compressed liquid) and the result is that the freezer will stop functioning.
So before you ship it out, remove it from its location, plug it in and first check if the compressor switches on or not.
If the compressor switches on then check if the fan is still working. If the fan does not work, buy a new one and install it. 99 % chance the system will work again.
If the fan is running however then check the evaporator. If that is covered in dust the high pressure liquid can also not be cooled and the fridge / freezer won't function properly.
If that is also not the case i fear the problem is worse, then you may have lost gas and that is possible if the fridge has been switched off for a prolonged period of time.
In the old days the pipes in the fridges and freezers were made of copper, which would not deteriorate. in modern fridges / freezers they changed the copper for aluminum, which is much cheaper. Only problem is that Aluminum becomes poreus if the fridge / freezer sits idle for a prolonged period of time. Then the gas escapes and it cannot be repaired.
An easy way to check whether you lost gas is to switch the system on. The top part of the compressor should become warm / hot. If it stays cold or a bit warm you have lost gas.

Hope you will be able to find out which one it is ?

Mambo, thanks for the diagnostic protocol. I can try those. I just can’t ship the thing out to a shop.

 

[Mambo42]

Mambo, thanks for the diagnostic protocol. I can try those. I just can’t ship the thing out to a shop.

No need to ship it out. If you can move it a bit forward you should be able to get access to the compressor / fan assembly and then you can literally do these tests in 5 min.
It will give you an indication of where the problem lies.

Of course it is always possible that a print plate corroded in the salt air but when it comes to cooling equipment in the majority of the cases it is one of these 3 options. So hope that is also the case in this situation.

 

[Comodave]

Checking the fan is a simple and easy thing to do. On our last boat the Vitrifugo refer didn’t cool well at all. I added a fan since it didn’t have one to begin with. Also the manufacturer had a vent into the cabinet but it was placed where it couldn’t work. I added a low vent to let cool air into the cabinet and a high vent to let the hot air out. The refer started working very well and would freeze ice cream when it never would before.

 

[PMF1984]

Checking the fan is a simple and easy thing to do. On our last boat the Vitrifugo refer didn’t cool well at all. I added a fan since it didn’t have one to begin with. Also the manufacturer had a vent into the cabinet but it was placed where it couldn’t work. I added a low vent to let cool air into the cabinet and a high vent to let the hot air out. The refer started working very well and would freeze ice cream when it never would before.

I got you. I have a couple of computer fans I have saved for this as the ventilation holes at the top and bottom of the back of the enclosure are not the recommended size.

 

[PMF1984]

After assembling some coolers tomorrow to move the food into I'll give this a try. I've had the thing out before, most recently for a hinge repair.

 

[Comodave]

I got you. I have a couple of computer fans I have saved for this as the ventilation holes at the top and bottom of the back of the enclosure are not the recommended size.

The Vitrifugo in our last boat had a terminal on the circuit board that had .5 amp capacity for a fan. I used a .05 amp fan so the draw was minimal. On our Isotherm refer I couldn’t find any documentation that showed an output for a fan. There is a fan on it though. So I added another .05 amp fan to help. I hooked it to the 12 supply lines with a fuse so whenever the 12 volts is turned on to the refer the fan runs. It is a small waste of power but worth it to help the refer cool well, and it works extremely well. But I have a lot of ventilation to the new refer along with the extra fan. The refer control goes from 1 to 8. On 8 it freezes stuff in the fridge section. We kept turning it down until we got to 3 and it freezes well and cools well in the fridge.

 

[O C Diver]

I added an Engel freezer to my boat for the summer cruising season. It's about the size of an 60 or 80 quart cooler and runs on either 12 VDC or 120 VAC. It's not as energy efficient as some chest freezers, but being able to put it wherever you can find space, is a big plus.

As a side note, what makes you think the refrigerator isn't going to completely die on the trip? When it's no longer keeping the freezer cold, I would be guessing it wouldn't last much longer.

Ted

 

[Lepke]

I've fixed a number of refers and freezers where the only problem was a stopped or slower running fan. Most small motors use some type of oilite bearings or bushings. When the impregnated lube is exhausted the fan slows or stops, but usually doesn't burn out. Re-oiling the bearings usually fixes the problem. But replacement oil doesn't last as long as the original lube, so they have to be re-oiled every few years. In some fan motors you can place compressed cotton next to the bearing and saturate with oil and it lasts a long time.

 

[PMF1984]

Problem went away? but how

So the freezer unit, which has its own compressor, fan and 12v/110v wire feed,
started getting "better".

Nevertheless I ordered a fan as whatever repair diagnostic I did would necessitate removing the unit, and since this was not something I wanted to repeat if I did need a new fan and the fan is older (I think for some reason 2008) the cost of the new fan would be minimal.

I ordered one from Beard Marine in Ft. Lauderdale and got it the next day.

So as I removed goods from the freezer I noticed the temp was 10 degrees F.
WTH, I have a new fan, I'm putting in a new fan.

One thing I noticed, the 110v power to the fridge had reversed polarity.
Had to be that way since 2017. Well I fixed that.

Wanted to tackle an aux. fan at my vent but can't figure out how to wire to both the Freezer and fridge so that the fan s come on if either boots up. Seems I wuld get some "backwash" into the unit not running.

 

[Comodave]

On our last boat the circuit board had a terminal for the fan. On our current boat the owners manual didn’t show that so I just hooked the fan to the 12 volt supply to the refer. That way the fan runs whenever the refer is powered on. I know it wastes a bit of power but the fan only draws .05 amp so it isn’t too bad. But the refer works extremely well.

 

[PMF1984]

Dave,
Yes I cold do that, but also want the fans to kick in when the freezer unit starts.

 

[Comodave]

My fan runs whenever the refer is powered on. If you power both of them on at the same time then it would work for both.

This is the fan I got on Amazon.

Noctua NF-F12 PWM, Premium Quiet Fan, 4-Pin (120mm, Brown)

 

[Bmarler]

Dave,
Yes I cold do that, but also want the fans to kick in when the freezer unit starts.

If you want either compressor to run the fans, you need to put in two relays. Power the relay coils from the compressor motor leads, then route the fan wiring through the normally open contacts so that either relay makes the fans run.

 

[PMF1984]

BMarler,

A relay sounds like what I want (but I'd have to read up on them).

The fans are always "hot" as the switch in the control unit is on the return line.

I don't see how I could avoid putting that load on the control unit.

maybe a separate switch that the fridge or freezer power turns on with a secondary power source and return?

 

[Bmarler]

BMarler,

A relay sounds like what I want (but I'd have to read up on them).

The fans are always "hot" as the switch in the control unit is on the return line.

I don't see how I could avoid putting that load on the control unit.

maybe a separate switch that the fridge or freezer power turns on with a secondary power source and return?

The idea would be to use the fan circuit to power the relay coil. The power for the fan would route through the relay contacts. That power can come from the dc plus terminal if there’s enough ampacity to run the fan, (most likely) or you can bring power in specifically for the fan from somewhere else. Obviously, it makes the most sense to just use the dc plus terminal.

 

[C lectric]

You can operate a fan to evacuate the fridge cavity by mounting a 100mA x 12DC volt fan of about 3.5" to 4" to blow out from the cavity.

It can be driven by the two leads that feed the cooling motor by attaching the fan leads directly to the motor leads in parallel with the motor leads. Suggest at the clip on leads on the controller.

The controller controls the cooling motor by grounding the negative lead which is opposite from N.A. thinking but also not uncommon here.

OR

you can do the same with a small 12V single pole N.O. relay by Omron or another mfgr. These small relays usually only draw about 40mA at 12VDC so even less draw on the actual fan part of the circuit and then the relay can switch the fan power on/off from the battery leads.
Just fuse the fan though and purchase the clip that holds the relay into the base so the relay cannot wiggle free..

 

[Bmarler]

You can operate a fan to evacuate the fridge cavity by mounting a 100mA x 12DC volt fan of about 3.5" to 4" to blow out from the cavity.

It can be driven by the two leads that feed the cooling motor by attaching the fan leads directly to the motor leads in parallel with the motor leads. Suggest at the clip on leads on the controller.

The controller controls the cooling motor by grounding the negative lead which is opposite from N.A. thinking but also not uncommon here.

OR

you can do the same with a small 12V single pole N.O. relay by Omron or another mfgr. These small relays usually only draw about 40mA at 12VDC so even less draw on the actual fan part of the circuit and then the relay can switch the fan power on/off from the battery leads.
Just fuse the fan though and purchase the clip that holds the relay into the base so the relay cannot wiggle free..

driving the fan from either compressor was the issue. that's why i suggested the pair of relays. either one energizes the fan and the two systems remain isolated.