Mystery in my Freezer

mysticmd · February 20, 2015

This one has me bewildered. I have one of those small Dometic refrig. with freezer on top. We're not on the road full time yet, but it is plugged in full time at the house, and I do store food in the freezer, but it is checked regularly, I'm in and out of it, I make sure the little green light is on, check for mice in the trailer (traps), etc. Getting ready to go on a trip next week and I want to take a survey of what is in the freezer. It has been freezing temps here day and night, never higher than 22 today and is parked under a big, open port/canopy. I open the freezer and the little shelf in the top back had a bag of frozen spinach, a bag of frozen burgers, and the lower part had a row or frozen water bottles and on top of that was a large container of puff pastry filled spinach/feta cheese and a pack of Omaha Steak hot dogs. Both of those items were as defrosted as if I had left them sitting on the kitchen counter. Cool, not cold, not frozen. In the container of the puff pastries was frost on the inside. There is heavy frost in a band about 6" wide on the back wall of the freezer which has been there since last summer and needs to be manually defrosted. That doesn't appear to have changed and there was no water from a defrosting freezer in the small tray in the back of the top of the fridge. I checked the thermometer in the fridge -- 18 degrees; moved it to the freezer - 18 degrees, brought it into the basement and it quickly moved up to 40, so I know it is functioning, so put it back int he freezer and moved it around and it appears to be consistent top, bottom, left side, right side (it's not that large an area). This doesn't make sense - does it? Any ideas? And now, I can't trust my freezer - even in freezing temps in winter. Thanks for any suggestions.

SIBERNUT · February 20, 2015

It's got to do with the same problem a heat pump AC unit has, ambient air too cold. Better people on here to explain it.

Wanted to mention a boaters trick- put an ice cube in a cup in the freezer when you leave the unit for a few days. If it's melted on your return, you lost power & the food could make you sick.

mysticmd · February 20, 2015

Hi Sibernut, I understand what you are saying. Where it is parked in SC it is rare to have temps fall below the inside temp of the frig/freezer, but we're having the same wild Arctic winds as a good portion of the rest of the country, about 30 degrees below the norm for here. Thanks for the ice cube trick, will do.

Kirk W · February 20, 2015

This doesn't make sense - does it? Any ideas? And now, I can't trust my freezer - even in freezing temps in winter. Thanks for any suggestions.

It sounds like you may have experienced an issue that is not well known but is normal for absorption refrigerators. For one to operate properly the heat source must be able to cause the liquid refrigerant in the unit to boil and change into a vapor form. The heat sources in RV refrigerators are quite small and the electric one is smaller than that of the propane so propane will operate to a lower temperature than electric, but either one will cease to cool if the boiling action stops. While some air movement through the refrigerator is needed for it to operate, in very cold weather it is most effective to at least partially block the vents into the bottom of the cooling unit and many of us even add some outside heat but keeping an incandescent light burning inside. It is also very important to prevent wind from blowing into the vents when temperatures get done into the teens or below. Just how cold it will continue to work depends upon wind conditions, and several other factors. At some point above 0° almost all RV refrigerators will fail to operate but will start again as ambient temperatures start to rise.

skp51443 · February 20, 2015

Do you have a low ambient temp switch on your fridge? Usually tucked in around the door opening on the ones I've seen. Some have two switches, some one. I think that they control a door seal heater and the interior light, turning them or it on will add a bit of heat to the fridge interior causing it to cycle the cooling system as well as preventing condensation along the seals.

Not a cure but it lowers the working outside air temp range a bit.

mysticmd · February 20, 2015

First, thank you Sibernut, Stanley, Bill, and Kirk for fast responses, your knowledgeable explanations, and refrigerant tips. I will be passing these on to my husband. As soon as the temp gets a bit warmer today (at zero right now in SC), I'll be checking for that extra switch in the fridge door. Like the ice cube trick, too. Yes, we have had unusually severe, low temps for days now with one or two more to go before it gets a wee bit above freezing and some wicked winds for days now. Never knew my foods could be defrosting. I've forwarded your responses on to some of my other RVing friends so they don't lose food or poison themselves with bad food. I'm very new to this club; joined with the anticipation of going FT in a few years, and find there is a plethora of valuable information, suggestions, ideas, and opinions that in and of itself makes the membership well worth the price. I look forward to eventually meeting you Escapees in person as we travel more. Heading to Edisto Island Beach in SC soon -- a beautiful,long, empty beach with tidal marshes to watch the waterfowl and spectacular sunsets, lots of great shells, and we can legally take our two Gr Shepherds on the beach. Camping is either tucked away in the woods offering a nice bit of seclusion, or a circular campground on the beach backing up to the marsh with the front part facing the ocean behind the sand dunes. Thanks again! - Mary

skp51443 · February 20, 2015

Once you get to go fulltiming there is another ice trick you really want to try. Go outside each morning and pick up your water hose, if it is stiff and crackly move south 200 miles. :-)

Good luck on the fridge.

rvrev2 · February 21, 2015

Once you get to go fulltiming there is another ice trick you really want to try. Go outside each morning and pick up your water hose, if it is stiff and crackly move south 200 miles. :-)

Good luck on the fridge.

Now that is just good advice right there!

Is it really just for full-timers only?

Jim & Alice · February 21, 2015

Ya don't have to use a hose... just tie a snow shovel on the rear, start driving South, and stop when someone asks you, "What's that strange thing on yer bumper?"

HB

mysticmd · February 21, 2015

Well, we thought we had done all those suggestions -- took one snow shovel with us and went from NJ to NC to the northern area of SC; we now need another snow shovel and they don't even sell good ones down here and Amazon ran out! This year has been more ice, though, and did bring the ice scraper along with skis, snowshoes and tobaggon - which pretty much have become ornaments. Yesterday morning was about 4 degrees, wind finally stopped, maybe the freezer will behave. I did initially expect to get a run of funny answers like RV poltergeists hiding behind the fridge. Looking forward to the fun with you guys! -- Mary

Dutch_12078 · February 21, 2015

Our Norcold fridge works well down into single digit temps, but I do cover the lower outside vents with wide masking tape when it gets that low. I also know folks that have put a 75 or 100 watt light bulb in the bottom of the outside fridge access with the vents sealed as well in extreme temps. We use a dual sensor remote temperature monitor that records the fridge and freezer high and low temps. It will also sound an alarm if the temps get too high.

mysticmd · February 21, 2015

Dear Dutch 12078 - so glad you posted. I'm in the process of packing the trailer to leave and I was just telling my husband that not only do I think the freezer is not working on the coldest setting, but I don't think the fridge is working. Yesterday it was reading 18-19, today 20, even though I set it colder. My heart was sinking and I'm already thinking: bring the big cooler, we'll use ice, eat out a bit, etc. So after reading your timely post to my husband, he said: okay, something is frozen, so let's put the heat on - which is where we are now. I'll post more and hopefully will be saying, it thawed out and we're up and running normally and lessons learned about extreme temps, ambient air, vents, all the little tricks of Rving. Happy it happened at home and not on the road; 8 yrs and still new situations are cropping up. Thanks, Escapees!

mysticmd · February 21, 2015

Update: With furnace on in trailer, the temperature in the frig and freezer has started to drop..... sounds crazy backwards, right?!

Still wondering with single digit temps outside and in trailer, how does the food defrost? What is producing enough heat to thaw food under those conditions and it was sitting on a row of frozen water bottles; what am I missing? Guess I need another refrigeration lesson.

Kirk W · February 22, 2015

Update: With furnace on in trailer, the temperature in the frig and freezer has started to drop..... sounds crazy backwards, right?!

Not to me it doesn't. The reason is that with the inside temperature warming up there is some heat lost into the rear of the refrigerator to get the area up to a temperature that enables the boiler to work once more and boiling is required for the coolant to do it's work. It is a basic law of physics that says that when a gas expands it will absorb energy, or heat. If the refrigerant does not boil and change to vapor, it can not cool the refrigerator.

As to the food thawing while the water stays frozen, different substances freeze at different temperatures. It takes a lower temperature to keep ice cream froze than it does for water(ice). Some foods thaw much more easily than others.

mysticmd · February 22, 2015

Okay, back to normal mode in the fridge and freezer. Put the heater on about 50 degrees last night and left it on, plus the outside temperature was 40 overnight. We've been camping in frigid conditions before, but , of course, the heat was on inside. Possibly in the last 8 yrs we have never experienced the combination of extreme conditions of freezing night and day and severe, steady winds for several days while the trailer was immobile at home with the heat off. Lessons learned. Thanks everyone that responded. :rolleyes: