HTP EL-399NVWH - Manual (Page 16)

16
LP- 346 REV. 3.20.14
allows the cold feed to flow through the storage tank first. It is recommended that you install shut off valves on the cold feed line for
future ease of service. If there is a back flow preventer or any type of no return valve in the system, then you must install an additional
tee for a suitable potable hot water expansion tank. Connect the storage tank return line to the return connection located on the heater
(shown in Piping Details, Section J). Then connect the storage tank hot water outlet to the hot water plumbing lines.
B. RELIEF VALVE
Connect discharge piping to a safe disposal location following the guidelines below.
To avoid water damage or scalding due to relief valve operation:

Discharge line must be connected to relief valve outlet and run to a safe place of disposal. Terminate the discharge line in a
manner that will prevent possibility of severe burns or property damage should the relief valve discharge.

Discharge line must be as short as possible and the same size as the valve discharge connection throughout its entire length.

Discharge line must pitch downward from the valv e and terminate at least 6” above the floor drain, making discharge clearly
visible.

Discharge line shall terminate plain, not threaded, with a material serviceable for temperatures of 375
o
F or greater.

Do not pipe discharge to any location where freezing could occur.

No shutoff valve may be installed between the relief valve and heater or in the discharge line. Do not plug or place any
obstruction in the discharge line.

Test the operation of the relief valve after filling and pressurizing the system by lifting the lever. Make sure the valve
discharges freely. If the valve fails to operate correctly, replace it with a new relief valve.
 Test relief valve at least once annually to ensure the waterway is clear. If valve does not operate, turn the heater “off” and call
a plumber immediately.

Take care whenever operating relief valve to avoid scalding injury or property damage.

For heaters installed with only a pressure relief valve, the separate storage vessel must have a temperature and pressure
relief valve installed. This relief valve shall comply with Relief Valves for Hot Water Supply Systems, ANSI Z21.22 CSA4.4.
FAILURE TO COMPLY WITH THE ABOVE GUIDELINES COULD RESULT IN FAILURE OF RELIEF VALVE OPERATION,
RESULTING IN POSSIBILITY OF SUBSTANTIAL PROPERTY DAMAGE, SEVERE PERSONAL INJURY, OR DEATH.
C. BACKFLOW PREVENTER
Use a backflow preventer specifically designed for potable water installations. This valve should be installed on the cold water fill supply
line per local codes (see Piping Details, Section J).
D. SYSTEM WATER PIPING METHODS
EXPANSION TANK AND MAKE-UP WATER
1. Ensure that the expansion tank is designed for potable water installations and sized to correctly handle system water volume and
temperature.
Expansion tanks must be sized according to total system volume. This includes all length of pipe, all fixtures, heaters, etc. Failure to
properly size system expansion could result in wasted time, money, and possible property damage, personal injury, or death.
Elite VWH EXPANSION TANK SIZING
EL-80 VWH 1.4 Gallons + Storage Tank Selected (60, 80, 119, or 175)
EL-110 VWH 1.7 Gallons + Storage Tank Selected (60, 80, 119, or 175)
EL-150 VWH 2.0 Gallons + Storage Tank Selected (60, 80, 119, or 175)
EL-220 VWH 2.6 Gallons + Storage Tank Selected (60, 80, 119, or 175)
EL-299/301 VWH 3.1 Gallons + Storage Tank Selected (60, 80, 119, or 175)
EL-399 VWH 3.7 Gallons + Storage Tank Selected (60, 80, 119, or 175)
Table 2