Washington State Conservation Fact Sheet

• Project Type: General OWC
• Applicant: Grand Junction - City of
• Project Name: Grand Junction Retrofit Pilot Project
• Title: Hot Water Conservation Fact Sheet
• County: Mesa
• Water Conservation - Doc Type: Reports

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If you have a gas-fired water heater, here's how to turn down the thermostat:

1. Locate the thermostat. It's usually in a small box at the base of the heater and has a round
dial on its face.

2. The dial is usually marked warm at one side an~ hot at the other with marks in between, but
no temperatures indicated.

3. Turn the dial several marks towards the side marked warm.

4. The following day check the temperature of the water at the tap using a thermometer and
adjust the thermostat accordingly.

. Insulate Your Water Heater

Most water heaters lose heat quite rapidly because ~hey come from the manufacturer with only 1"
to 1!" of fiberglass insulation (about R-5). To redliJce heat loss you can wrap your water heater
with an additional jacket of fiberglass insulation; Most utilities make hot water tank wraps
available to their customers free of charge (or at cost) and many utilities will do the installation
for you. Others provide the tank wrap, but require the customer to do the installation. If you
install your own, be sure to carefully follow the instructions that come with the tank wrap kit. Do
not put insulation over the thermostat cover plates.

Most tank wraps have an insulating value of R-5 <ilr R-12. By installing an R-12 wrap you can
expect to save between 400 and 600 kWh per yeat. At today's energy prices this will save you
between $12 and $21 a year.

If you have a gas water heater, it is also a good idea to insulate the tank. It's recommended that
you purchase a commercially available insulating blanket made specifically for a gas water heater.
Such blankets are designed so that they won't block the air intake and so that insulation will not
come in contact with the flue. This is essential fOr both proper functioning of the heater and in
order to avoid a potential fire hazard,

. Thermal Traps

A hot water tank has both a cold water inlet arid a 'hot water outlet. As a result of natural
convection, water passes from the tank and heats both the inlet and outlet pipes. If the hot water
outlet runs vertically from the water heater to the, second story, there can be significant heat loss
over its entire length.

To reduce this heat loss, a thermal trap can be installed just above the tank. A thermal trap is
simply a loop of pipe that interrupts normal convec~ion patterns. Heat flow stops at the top of the
loop instead of continuing to rise. Thermal traps dan be installed on both the cold water inlet and
the hot water outlet. It is best to insulate the thermal trap to R-7 to further reduce heat loss.
Thermal traps can be expected to reduce energy consumption by roughly seven to nine percent.

. Pipe Insulation

Insulating your hot water lines will save energy., Minimally, you can expect a savings of about
three percent. The extent of savings will depend c/n both household water use patterns as well as
the actual lengths of pipe that the hot water mfJst flow through. If you use water frequently
throughout the day, or if the pipe runs are long, or H they pass through an uninsulated crawl space,
pipe insulation at R-4 can result in a savings of abo)Jt five percent.

Pipe insulation is available in several different forms. Most common are the closed cell flexible
foams. They usually corne in tubes four to six feet long and in various diameters. Tubes can be
fitted around pipes by either slitting them, or' in some cases, using a slit provided by the

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