Tag Archives: Refrigerator
Is Your Old Refrigerator Running Optimally? Tips On Saving Energy In The Kitchen
Unless your fridge is so old or worn out that you’ve already chosen to replace it with an energy efficient fridge, you really should do a simple assessment of whether the fridge is running well. Issues such as how often and for how long the compressor motor runs, whether there’s frost in the freezer section, how good your door seals are, and the temperature range of the freezer and fridge sections, can all impact your refrigerator energy use. Begin by simply trying to remember how frequently you hear the motor going. Does it seem to be going continuously, or is the refrigerator usually silent? Does the compressor seem to keep switching on and off (short periods of running time, then short rests)? During times of the day when the fridge door stays shut (for example overnight), the pattern of energy use for energy saving fridges is typically that of short periods with the motor working, interspersed with much longer periods of the compressor motor resting. If that’s how your fridge behaves, you’re off to a good start. If the compressor motor is going nearly all the time, there may be issues with the gasket seal, or cobwebs on the coils, or the fridge may be in an enclosed area so that the heat the motor is working to extract from the interior has nowhere to escape to. You may just have an old refrigerator with an inefficient compressor motor, which translates into less heat extracted for a given amount of electricity input, or you might have substandard 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 refrigerator or the freezer compartment. Next look for ice build-up in the freezer compartment. Fast or heavy frost build-up in a manual-defrost freezer is usually an indication that warm, moist air is getting into the freezer section. You could have a poor seal on the freezer compartment, which allows cold air to escape through the seal, and warm, moist air to enter in its place. It takes more power to extract heat from moist air than from dry air, so you win on two fronts by eliminating air leaks. Even if you have a great seal, you should defrost a manual-defrost freezer regularly. You should never let more than a quarter inch of ice form on the compartment walls, as it makes the compressor motor work harder. Check your refrigerator and freezer compartment gaskets to make sure you have a good seal. The standard test is the dollar-bill check. Open the refrigerator or freezer door so that you can slide a dollar bill halfway in, then close the door. If the bill stays tightly in place when you pull, the seal is fine in that part of the gasket. Do the same at several other points along the gasket. If at any point the bill slides out, or moves freely, try moving the bill along the seal in each direction until it sticks. That should give you an idea of how big each leak is. You can sometimes solve gasket leaks by cleaning the gasket to remove any residue that might prevent a good seal. But if there are gaps and the gasket is clean, you really should replace the seal. Your refrigerator may pass the dollar bill test even though the gasket is letting in air – if the gasket is cracked. Cracks can open up in the thin part of the gasket where it attaches to the door. Run your finger along the gasket feeling for rips, all the way around each door. If you’re a DIY type, gaskets can be fairly cheap to replace. I bought a new gasket for my refrigerator five years ago and with no previous instruction had it on the door within a half hour. And an appliance repair person can install one even faster, especially if you tell them to bring a replacement gasket with them when you call them. So if your gasket is leaking or too rigid to provide a good seal, get it replaced. What are the ideal temperatures for your fridge and freezer sections? The last thing to look at in your do-it-yourself fridge assessment is the temperature in each compartment of your refrigerator. You can use either a standard glass thermometer or an electronic probe thermometer to do this. Place the thermometer (or the probe portion, for an electronic thermometer) in a jar half-filled with liquid (a pickle jar does nicely), and leave it in the compartment for a full 24 hours. (Make sure the jar is only half filled with liquid for the freezer compartment, 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 on the thermometer. For the fridge compartment, you should strive for 39F or 40F (or 4C). For the freezer temperature, go for 5F (or -15C). If the refrigerator temperature or freezer temperature is lower than this, you are wasting energy cooling your food more than necessary. Remember that for chest or upright freezers, where frozen food tends to be kept longer than in the freezer compartment of refrigerators, you want a somewhat lower freezer temperature of 0F or -17C. If the compartment is not at the ideal setting, adjust the thermostat in the appropriate section up or down by just a small amount. Then wait another 24 hours and take a second reading. It’s best to tweak the thermostat a little at a time, until you reach the ideal refrigerator temperature. Once you reach that ideal setting, you can use a permanent marker to draw a line on the thermostat dial, so you have a reference point. It’s not a given that this will always give you the ideal temperature (thermostats can be finicky) but if you subsequently notice that the line is far from the front, you’ll know to measure the temperature once more. It’s important to measure your refrigerator temperature (both compartments) on a monthly basis, or at least, if you have already checked it and have marked the position of the thermostat dial, to see that the dial hasn’t moved. It’s easy for these dials to get turned inadvertently, or on purpose by little hands, and if the temperature varies far from the proper settings of 40F for the fridge section or 5F for the freezer section, you either risk food spoilage or a higher electricity bill. Robin Green owns Green-Energy-Efficient-Homes.com, a website that helps people find ways to use less energy at home. For more on saving electricity with your fridge, see Energy saving refrigerators and Energy efficient freezers on Green Energy Efficient Homes.
How Much Energy Does Your Refrigerator Consume? How To Find Out On Your Terms
Before you rush out and get a new energy saving refrigerator, it’s important to understand how much energy your old fridge consumes. Why? For three reasons. First, because you’ll be looking at Energy Guide labels on the new fridges, to find out which ones will cost the least to operate, and you might as well have an idea of how they compare to your existing refrigerator. Second, if you want to replace your fridge mainly to save electricity, you may find out that you don’t need to. While today’s refrigerators are far more efficient than those of ten years ago, your fridge may turn out to be efficient enough that there isn’t a convincing motivation to replace it. You might save more money on energy, for the same investment, on weatherproofing or a new window or two. Third, you may discover your existing fridge uses so much energy, that a refrigerator tune-up will save you money even in the short time before you buy the new unit. Things that can really help are: checking the gaskets for leaks or cracks, checking the temperature in both compartments (38-40F for fridge, 5F for freezer), ensuring the compressor and coils are dust free; and keeping good air circulation around the unit. Even if you find out that your old refrigerator is an electricity hog and you do a tune-up, you might find that the tune-up on its own will result in big electricity savings. Your current refrigerator could easily be costing you $25 to $125 a year more than it should, and your new refrigerator may turn out to be less efficient than its ENERGY STAR label claims, depending on how you use it. But if you merely assume that a refrigerator uses what its label claims, you’ll be leaving a big opportunity on the table. What if I told you that $20 could save you at least $40 a year, every year? It turns out that there is an inexpensive device that can do just what we’re after: measure the energy consumption of your fridge. I bought a Kill A Watt meter about five years back and have used it to measure the energy consumption of many appliances in my house. I have also lent it to friends and family so that they could uncover energy savings of their own. These meters are available for about $20 and they measure how many kilowatt hours per day (kwh/day) an appliance like a fridge consumes. A measurement takes about three days, because a fridge cycles on and off, and only a longer measurement irons out the peaks and valleys of the refrigerator’s electricity use. But once you have that reading, you will know what your refrigerator consumes and you can start choosing actions to save electricity, or you can make a more sound decision about replacing your old refrigerator. The Kill A Watt meter measures electricity use in several ways. The important readings for our purposes are time elapsed and kilowatt hours used. The Kill A Watt meter measures both of these values from the moment it is plugged in, so if you plug in the meter, then plug your fridge into the meter soon after, you’ll start to see how much electricity your refrigerator uses once a minimum of 24 hours have passed. Follow these steps: 1. Pull your refrigerator out from the wall. Unplug it and plug an extension cord into the wall outlet instead. 2. Plug the Kill A Watt meter into the other end of the extension cord, and the fridge plug into that. Leave the meter where its display is visible. 3. Push the fridge back. (You can just stick the Kill A Watt meter between the wall socket and the refrigerator, if that allows you to see the meter while you’re taking the measurement.) 4. Wait at least 36 hours to measure. Ideally you should wait 48 to 96 hours. If you keep pressing the red button on the Kill A Watt meter you will see readings for, among others, the hours and minutes elapsed, and the kilowatt hours consumed. You can compute kilowatt hours per day using the following formula: kwh/day = kwh / ((hours/24)+(minutes/1440)) So if the final reading is 2.37 kwh and the elapsed time is 34h22m, the consumption would be 2.37 / ((34/24)+(22/1440)), or 1.655 kwh/day. Don’t wait more than four days to do your reading, because the time elapsed measurement wraps back to zero at 99h59m. Most fridges are rated in terms of kilowatt hours consumed per year, so to compare your existing refrigerator with what’s available now, you can multiply the kwh/day result by 365. Our hypothetical fridge which we determined uses 1.655 kwh/day consumes 604 kwh/year. A 16 cubic foot Sun Frost fridge, in comparison – one of the most efficient refrigerators available – consumes only 254 kwh/year. You can see how your existing fridge stacks up against new models by searching the www.energystar.gov database, for models that share features of your refrigerator. Fridge efficiency standards have gone up in recent years, and a fridge typically consumes more energy as it ages, due to worn gaskets, dust buildup on compressor and coils, wear and tear on the motor, and occasionally loss of refrigerant. And ENERGY STAR rated refrigerators must be at least 20% more efficient than the standard, so if you own an old refrigerator that was not ENERGY STAR rated when you bought it, you can see there is a big potential for savings, especially if you know your current consumption. The efficiency requirement for refrigerators varies based on configuration (top or bottom freezer, side-by-side, or no freezer), volume, defrost features, and refrigerant type. And the formula is so convoluted that few people other than US EPA and DOE officials, and appliance company engineers, can really grasp it. So rather than quote the standard let’s look at a couple of examples. An ENERGY STAR rated, 10 cubic foot, auto defrost unit that consumes 309 kilowatt hours per year, is 21% better than the minimum required for its category. A 14 cubic foot partially automatic defrost unit that uses 254 kilowatt hours per year, is an amazing 36% better than the standard specifies. As you can see, even for units that sport an ENERGY STAR logo, there is a wide range of efficiencies, and don’t forget that a large unit that exceeds the standard by 36% may still use more energy than a smaller fridge that exceeds the standard by only 20%, if the minimum standard for the two fridges is different. If you can choose a smaller refrigerator when you buy a new one, you will certainly save more energy. Once you have measured how much electricity your refrigerator uses (it will probably be in the range of 400 and 600 kilowatt hours per year, depending on the size of unit, or even more if you have wasteful features such as side-by-side doors or an exterior ice and cold water dispenser) you can compare the consumption of your unit to those at the ENERGY STAR website, and see if it’s time to do a refrigerator tune up, or replace your refrigerator altogether. If you’re in luck, you might discover that the model you have now is already an energy saving refrigerator. If not, at least you’ll have a great tool for seeing if your new fridge measures up to its billing. Robin Green owns Green-Energy-Efficient-Homes.com, a website that helps people cut their home energy use. For more on saving electricity with your fridge, see Energy saving refrigerators and Kill A Watt meter on Green Energy Efficient Homes.