HTP EVC115 - Manual (Page 10)

10
LP-379 REV. 3.25.14
1. On 10, 15, and 20 gallon models, install a shut-off valve and the combination inlet / drain valve to the inlet connection near the
bottom of heater. On all other models, install a shut-off valve on the inlet connection on the top of heater. Connect the cold water supply
line to the shut-off valve. Refer to Piping Detail, Figure 4.
2. Connect hot water line to the
connection marked “HOT” on the top of the heater.
3. An opening is provided near the top of the heater for installation of a Temperature and Pressure Relief Valve (T&P Valve).
4. On 30, 40, 50, 80, and 115 gallon models, install a drain valve in the opening provided on the bottom of the water heater.
C. THERMAL EXPANSION
A check valve may be installed in the cold water inlet line as a separate backflow preventer, or may be part of a pressure reducing
valve, water meter, or water softener. An “open water system” refers to a system without a check valve. A “closed water system”
refers to a system with a check valve installed in the cold water inlet line.
As water is heated, it expands in volume and increases pressure within the water system. This action is referred to as “thermal
expansion
”. In an open water system, expanding water which exceeds the capacity of the system flows back into the city main where
pressure is easily dissipated.
A closed water system prevents expanding water from flowing back into the city main. The resulting thermal expansion can rapidly
increase pressure in the water heater and system piping. This rapid pressure increase can exceed the safety setting of the relief valve,
causing it to operate during each heating cycle. This rapid and repeated expansion and contraction of components in the system can
cause premature failure of system components, including the relief valve and possibly the water heater. Replacing the relief valve will
not correct thermal expansion.
A potable hot water expansion tank is required to offset thermal expansion. Expansion tanks are designed with an air cushion built in
that compresses as system pressure increases, thereby relieving the overpressure condition and eliminating repeated operation of the
relief valve. This expansion tank should be installed in the cold water line between the water heater and the check valve, and must be
sized for the entire water volume of the hot water system. See Figure 3.
Other methods of controlling thermal expansion are available. Check with the local water utility to determine if a check valve exists
in the cold water inlet line. Contact your installing contractor, water supplier, or plumbing inspector for additional information regarding
thermal expansion.
D. CONDENSATION
Condensation can form on the water heater when it is first filled with water, and may also occur with a heavy water draw and very cold
inlet water temperature. This condition is not unusual and will disappear as the water becomes heated. However, if the condensation
should continue, examine the piping and fittings for possible leaks.
E. INSULATION BLANKETS
Insulation blankets for external use on electric water heaters are not necessary with this water heater. An insulation blanket is meant to
reduce the standby heat loss encountered with storage tank heaters. This water heater meets or exceeds National Appliance Energy
Conservation Act standards with respect to insulation and standby loss requirements, thus making an insulation blanket unnecessary.
The manufacturer’s warranty does not cover any damage or defect caused by installation, attachment, or use of any type of energy
saving or other unapproved devices (other than those authorized by the manufacturer) into, onto, or in conjunction with the water
heater. The use of unauthorized energy saving devices may shorten the life of the water heater and endanger life and property. The
manufacturer disclaims any responsibility for any losses or injuries resulting from the use of such unauthorized devices.
If local codes require external appl ication of insulation blanket kits the manufacturer’s instructions included with the kit must be carefully
followed.
In addition, pay careful attention to the following so as not to restrict the proper function and operation of the water heater:

Do not cover the operating or warning labels attached to the water heater or attempt to relocate them on the exterior of the
insulation blanket.

Do not apply insulation to the top of the water heater. This could interfere with the safe operation of the electrical junction box.

Do not cover the jacket access panel(s) to the thermostat(s) and heating element(s), or temperature and pressure relief valve.

Inspect the insulation blanket frequently.
Failure to follow these instructions could result in substantial property damage, severe personal injury, or death.
F. TEMPERATURE AND PRESSURE RELIEF VALVE
NOTE: For protection against excessive pressures and temperatures in this water heater, install temperature and pressure protective
equipment as required by local codes, but not less than a combination T&P valve meeting the requirements for Relief Valves and