Is your old refrigerator working efficiently? Tips on saving energy in the kitchen.
Unless your refrigerator is so old or inefficient that you've already chosen to replace it with an energy saving fridge, it's wise to do an easy test to see if the refrigerator is running efficiently. Issues like how often and for how long the motor runs, whether there's frost in the freezer section, how good your door gaskets are, and the temperature of the freezer and refrigerator sections, can all affect your refrigerator energy efficiency.
Begin by simply observing how often you hear the motor going. Does it seem to be on all the time, or is the refrigerator mostly idle? Does the compressor seem to keep switching on and off (short bursts of running time followed by short periods off)? When the fridge door stays shut (for example overnight), the behavior of electricity consumption for energy efficient refrigerators is usually that of short periods with the motor working, followed by much longer periods of the compressor motor switched off. If that's how your fridge operates, you're off to a good start.
If the compressor is on almost constantly, there could be problems with the seal of the door gaskets, or dirt on the coils, or the refrigerator may be in an enclosed area so that the heat the compressor motor is working to extract from the inside has no place to escape to. You might just have an old refrigerator with an inefficient compressor, which translates into less heat extracted for a given electricity consumption, or you may have degraded insulation in the fridge walls, so that more heat flows in through the fridge sides. Or you might have set the temperature too low in either the fridge or the freezer compartment.
Next look for ice build-up in the freezer compartment. Rapid or heavy ice build-up in a manual-defrost freezer is usually a sign that warm, moist air is getting into the freezer compartment. You may have a bad seal on the freezer compartment, which allows cold air to escape between the gasket and the door, and warm, humid air to enter in its place. It takes more electricity to extract heat from moist air than from dry air, so you save on two fronts by avoiding air leaks. Even if you have a perfect seal, you should defrost a manual-defrost freezer frequently. You should never let more than a quarter inch of frost build up on the freezer walls, as the frost makes the compressor motor use more electricity.
Check your refrigerator and freezer section gaskets to make sure you have a good seal. The usual test is the dollar-bill check. Open the fridge or freezer door enough that you can slide a dollar bill partway in, then shut the door. If the bill stays tightly in place, the seal is fine in that section of the gasket. Repeat at several other points along the gasket. If at any point the bill slides out, or moves freely, try sliding the bill along the seal up and down until it sticks. That will give you a feeling for how big each leak is.
You can occasionally solve gasket leaks by cleaning the gasket to remove any bits of food residue that could be preventing a good seal. But if there are gaps and the gasket is clean, it's time to replace the gasket.
Your refrigerator may pass the dollar bill test even though air is getting in - if the gasket is ripped. Cracks can develop in the thin part of the gasket where it is attached to the door. So run your finger along the gasket and feel for breaks, all the way around each door.
If you are a do-it-yourselfer, gaskets can be relatively cheap to replace. I bought a new gasket for my fridge a few years ago and with no previous experience had it on the door within a half hour. An appliance repair person can install one even quicker, especially if you tell them to bring a replacement gasket before they make their service call. So if your gasket is leaky or torn, get a new one.
What are the proper temperature settings for your fridge and freezer compartments?
The last thing to look into in your do-it-yourself refrigerator check-up is the temperature in both sections of your fridge. You can use either a simple glass thermometer or an electronic probe thermometer to check temperatures. Put the thermometer (or the probe portion, for an electronic thermometer) in a jar half-filled with water (a pickle jar works well), and leave it in the compartment for a full 24 hours. (Make sure the jar is only half full for the freezer section, so the freezing doesn't break the jar. Don't open the unit for at least an hour before you do your 24-hour measurement. Check the temperature of the water in the jar. For the fridge compartment, you should try to achieve 39F or 40F (or 4C). For the freezer section, strive for 5F (or -15C). If the refrigerator temperature or freezer temperature is lower than the ideal settings, you are wasting energy cooling your food more than you need to.
Remember that for chest or full upright freezers, where food tends to be kept longer than in the freezer compartment of fridges, you want a slightly lower freezer temperature of 0F or -17C.
If the temperature is not at the proper setting, adjust the thermostat in the appropriate compartment upwards or downwards by just a small amount. Then wait another 24 hours and take a second measurement. It's best to tweak the thermostat a little at a time, until you reach the ideal refrigerator temperature. Once you get to that ideal setting, you can use a permanent marker to draw a line on the dial, so you have a reference point. There's no guarantee that this will always give you the correct temperature (thermostats can be temperamental) but if you subsequently notice that the mark is far from the front, you'll know to measure the compartment temperature once more.
It's important to measure your refrigerator temperature (both compartments) regularly, or at the very least, if you have already checked it and have marked the position of the dial, to check that the dial hasn't moved. It's easy for these dials to get turned inadvertently, or on purpose by a playful child, and if the temperature moves far from the proper settings of 40F for the fridge section or 5F for the freezer compartment, you either risk food spoilage or a higher energy bill.
