RV Refrigerator Efficiency 101

[markopolo]

RV Refrigerator Efficiency 101
By Mark Polk

RV refrigerators, for the most part, are efficient. In many cases it is something the owner does that makes the refrigerator less efficient.

There are several things we can do to help the refrigerator do its job more efficiently. First and foremost the RV must be fairly level for the refrigerator to operate properly. Older RV refrigerators required more precise leveling, but even the newer models need to be close to level for optimum performance. Over time a cooling unit operated out of level will be permanently damaged. Traveling with the refrigerator on will not cause problems because the liquids and gases in the cooling unit are constantly moving around. They don't collect and stay in areas of the cooling unit like they can in a stationary, out of level refrigerator.

The initial cool down process can take four to six hours. You should turn the refrigerator on the day before you plan to leave, and before you put any food in it. When you do load the refrigerator the food you put in should already be cold, and the food put in the freezer should already be frozen. Putting cold food in the refrigerator, rather than adding warm food, lets the refrigerator work less to cool down. One common mistake made is to over pack the refrigerator. There has to be space between the foods to allow for air to circulate throughout the compartment. In most situations you will have access to a store where you can buy food. A two to three day supply should be enough.

To assist with air circulation you can purchase an inexpensive, battery operated refrigerator fan. Put the batteries in and place the fan in the front of the refrigerator compartment blowing up. Cold air drops and warm air rises. The fan will improve the efficiency by circulating the air and it will reduce the initial cool down time by 50%.

The heat created by the cooling process is vented behind the refrigerator. Air enters through the outside lower refrigerator vent and helps to draft the hot air out through the roof vent. Periodically inspect the back of the refrigerator and the roof vent for any obstructions like bird nests, leaves or other debris that might prevent the heat from escaping.

To keep the refrigerator operating efficiently in the LP gas mode there is some routine maintenance you can perform. Remove the outside lower vent cover to access the back of the refrigerator. With the refrigerator turned off ensure all connections are clean and tight. Turn the refrigerator on in the LP gas mode and a look at the flame. If the flame is burning poorly, a yellow colored flame, or if the refrigerator isn’t operating properly in the gas mode it’s possible that the baffle inside the flue is covered with soot. Soot, rust and other debris can fall down and obstruct the burner assembly. When this happens it will be necessary to clean the flue and the burner assembly. Turn the refrigerator off again and locate the burner. Directly above the burner is the flue. The baffle is inside the flue. Wear a pair of safety glasses and use an air compressor to blow air up into the flue. After the flue is clean use the compressed air to remove any debris from the outside refrigerator compartment. Now, turn the refrigerator on in the LP gas mode to make sure it is working properly. Look for the bright blue flame. For a thorough cleaning of the flue and baffle it will be necessary to have your RV dealer do it for you. While it’s there have them to do an LP gas pressure test too.

Another good idea is to install a 12 volt, thermostatically controlled refrigerator vent fan at the back of the refrigerator, or at the top of the roof vent, to assist with drafting the hot air away from the refrigerator. If you are mechanically inclined these fans are fairly easy to install, or you can have your RV dealer install one for you. Either way it’s worth it. The fan removes the heat built up behind the refrigerator improving the refrigerators performance by up to 40%.

The outside temperature also affects the operation and efficiency of your RV refrigerator. When it’s cold out you can lower the temperature setting and when it’s hot out you can raise the setting. Some refrigerators are preset by the manufacturer. Extremely hot weather will directly affect the refrigerators efficiency. When it’s really hot outside try parking your RV with the side the refrigerator is on in the shade. Periodically inspect and clean the refrigerator door gaskets. Check them for a good seal. Place a dollar bill behind the seal and close the door. It should stay there and not drop. When you try to pull it out there should be some resistance felt. Do this in several different places and have any damaged seals replaced.

Try to limit the amount of times you open the refrigerator or freezer doors and the length of time you leave the doors open. Every time the door is opened it loses a few degrees of heat. On a hot summer day it won’t take long to lose all of its cooling capacity. Last but not least you should always have a thermostat in the food compartment. Food will begin to spoil at temperatures above 40 degrees.

RV absorption refrigerators do a great job for RVers. They will do an even better job, and last longer, if we apply these simple tips to make their job easier and less demanding.

Happy Camping,

Mark

Copyright 2006 by Mark J. Polk owner of RV Education 101

RV Expert Mark Polk, seen on TV, is the producer & host of America's most highly regarded series of DVD's, videos, books, and e-books. http://www.rveducation101.com/

Mark Polk is a retired U.S. Army Chief Warrant Officer Three, specializing in wheeled and track vehicle fleet maintenance operations. In addition to owning and operating RV Education 101, (based in North Carolina) since 1999, Polk also has a very extensive RV background working in RV service, sales and management. Polk has a degree in Industrial Management Technology and his 30 plus years of experience in maintenance includes working as an RV technician, a wheeled vehicle and power generation mechanic, an automotive maintenance technician, Battalion and Brigade level Maintenance Officer, an RV sales manager and also in the RV financing department as the Finance & Insurance manager. http://www.rveducation101.com/

Article Source: http://EzineArticles.com/?expert=Mark_Polk

[CAW]

3way Domestic ref. Working only on propane.

[GallenH]

What model Dometic? The following might help.

http://rvrefrigeratorrepair.com/wp-c...ervice-AES.pdf

[stevanpierce@gmail.com]

Solid advice when it comes to being level! I found it cools more efficiently when level.

I would assume that they operate best in preferred order of AC, gas, and DC. Is that a correct assumption?

[GallenH]

Originally Posted by stevanpierce@gmail.com

Solid advice when it comes to being level! I found it cools more efficiently when level.

I would assume that they operate best in preferred order of AC, gas, and DC. Is that a correct assumption?

That's the order on mine. Mine's over 20 years old but I would suspect the same of newer units.

[RossWilliams]

"One common mistake made is to over pack the refrigerator. There has to be space between the foods to allow for air to circulate throughout the compartment."

I don't think that is true. A packed refrigerator will hold cold longer than an empty one. In fact, adding jugs of cold water to fill empty spaces will provide thermal mass to maintain the temperature. Air circulation becomes important only when you put something into the refrigerator that needs to be cooled. Most modern refrigerators are well enough insulated that you aren't going to get warm spots next to the walls no matter how tightly packed. The one problem a packed refrigerator can create is cold spots that freeze food stored close to the freezer.

My two way dc/ac refrigerator doesn't need to be level and uses less power on DC than AC. And it cools off pretty quickly when turned on. The need for leveling and long cooling down periods are "features" of propane refrigerators.

[booster]

Originally Posted by RossWilliams

"One common mistake made is to over pack the refrigerator. There has to be space between the foods to allow for air to circulate throughout the compartment."

I don't think that is true. A packed refrigerator will hold cold longer than an empty one. In fact, adding jugs of cold water to fill empty spaces will provide thermal mass to maintain the temperature. Air circulation becomes important only when you put something into the refrigerator that needs to be cooled. Most modern refrigerators are well enough insulated that you aren't going to get warm spots next to the walls no matter how tightly packed. The one problem a packed refrigerator can create is cold spots that freeze food stored close to the freezer.

My two way dc/ac refrigerator doesn't need to be level and uses less power on DC than AC. And it cools off pretty quickly when turned on. The need for leveling and long cooling down periods are "features" of propane refrigerators.

I would not really agree with the idea that overpacking a frig is not an issue. The cooling source in RV frigs is normally in one place so the heat from the rest of the frig has to get there. It takes a long time conduct through solid objects like food to get to the cold source. Gravity will make the air circulate as it gets selectively warm by heat coming in through the outside of the frig or around the door seal, not just from warm stuff being put in the frig. Essentially every square inch of the walls door of the frig are at a warmer temp than the cold source and needs to get that heat to the cold source to be removed, and moving air will do it the fastest.


That said, we use the whole idea to advantage many times with our compressor frig. Our cold source is the freezer in the upper left of the cabinet, so we just sort out what products like to be warmer or colder and put them at the right area to be warmer or colder. Fruit and vegetables at the bottom, meats and other easily spoiled items closer to the frig, etc. Works well for us and the more full the frig is the larger the temp difference top to bottom.


All of this is easy to test, we have done it often. If you have a wireless thermometer in the frig, just move it around to different areas and see how big the difference in temp is. I think you will be surprised, as we certainly were, both when stuffed and non stuffed.