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Insualting Hot Water Tanks and Pipes
Insulating your hot water tank is an easy and inexpensive way to save money on your utility bills.By reducing the amount of heat that is lost through the wall of your water heater, you will save a lot of energy and therefore money.
Insulating a Storage Tank. Conventional storage tanks, due to their continual heating of water, generate the most standby heat loss, resulting in low efficiency ratings and wasted energy. Insulating both the tank and the surrounding hot water pipes will increase the efficiency of the system.
An insulating blanket can reduce standby heat loss by 25-40%, resulting in a 4-9% savings on your energy bill. A blanket’s cost ranges from only $10-20 and is generally easy to install.
Insulating blankets are available for conventional fuel-fired storage tanks, indirect system storage tanks, and electric storage hot water heaters. A blanket installed on an electric water heater will pay for itself in just one year. Rebates and even no-cost installations may be provided by your local utility.
Water heater manufacturers do not recommend insulating new water heaters with higher energy factors. These newer models already have a sufficient level of jacket insulation.
Caution should be used when insulating any type of gas-fired water heater. Added insulation should not be placed on the top near the exhaust vent or over any air intakes at the bottom.
Insulating Hot Water Pipes. First, determine the type of insulation you would like to install. There are four basic types of insulation, varying in R-value, which measures how well the insulation contains the heat.
Spiral-wrap Fiberglass Insulation: least expensive with the lowest R-Value of 1.6. This has one of the lowest R-values and is not recommended.
Foam Insulation: These foam tubes have a slit on the side so they can be easily
installed over existing pipes. After installation, you may want to tape all or some of the seams. Most foam pipe insulation comes in 3/8” thick walls, with an R-value of 2. Heavy-duty pipe insulation with 5/8” thick walls and an R-value of about 4 are available, but are slightly more expensive.
Self-sealing Foam Insulation: This foam tubing is fast and easy to install because no tape is needed to seal openings. After placing the insulation on the pipe, you can peel off the plastic strips and the foam tube seals itself with an adhesive material. Self-sealing foam tubing is available in R-2 and R-3 values.
Fiberglass pipe covers: This form of insulation consists of a rigid shell of fiberglass with a paper covering, and hinges open to go around the pipe. This type of insulation has an R-value of 2 and is used in cases where the temperature is high enough to damage foam insulation.
Installation. Typically, just the first five to 10 feet of pipe from the water heater need to be insulated.
After you decide on the type of insulation and map out the area in which you will insulate, follow these general directions for an efficient, safe insulation process:
Before insulating the pipes, check for any apparent water leaks. Tighten or repair any leaking joints.
Match the diameter of the insulating foam to the diameter of the pipe for a close fit.
Simply place the insulation over the pipe and situate the pipe sleeve so the seam will face down on the pipe.
If your insulation needs to be sealed; tape, wire, or clamp it to the pipe every two feet.
Cut shorter lengths of foam when necessary to bend around joints.
Do not compress the insulation or it will lose some of its insulating value.
On gas water heaters, keep insulation at least 6 inches from the flue and avoid the draft diverter.
The water in the pipes now will hold heat for much longer, and less energy is wasted during transport.
Other Ways to Conserve Energy. By simply lowering the setting of the water heater thermostat by 10°F, you will save 3-5% in energy costs. With a lower set temperature, the rate of heat loss decreases. If you are traveling, turn the thermostat to either the lowest setting or turn the heater off.
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Why is this important?
Insulating your hot water pipes is a cheap, effective way to minimize energy loss.
Insulating hot water pipes can actually raise water temperature at the water outlet by 2–4ºF, which lets you have a lower water temperature setting and thus save money and conserve energy.
Insulation will result in less wasted energy, less pollution and a lower utility bill. Since the water in the pipes can hold heat for longer, you won't waste as much water waiting for the water to get hot when you turn on the tap or shower.