HTP EL-399NVWH - Manual (Page 22)

22
LP- 346 REV. 3.20.14
Install the heater so the gas ignition system components are protected from water (dripping, spraying, etc.). Allow clearance for basic
service of heater circulator, valves and other components.
Observe the minimum 1” clearance around all uninsulated hot water pipes when openings around pipes are not protected by non-
combustible materials.
Basic steps are listed below, with illustration that will guide you through the installation of the heater.
1.
Connect the system return marked “Heater Return”.
2.
Connect the system supply marked “Heater Supply”.
3. Install a circulator as shown in piping details (this section). Make sure the circulator is properly sized for the system and friction loss.
4. Install an expansion tank on the system
. Consult the expansion tank manufacturer’s instruction manual (see Part 4, Section D for
water volume) for specific information relating to expansion tank installation. Size the expansion tank for the required system volume
and capacity.
5. Install a drain valve at the lowest point of the system. Note: The heater cannot be drained completely of water without purging the
unit with an air pressure of 15 PSI.
6. The relief valve and temperature and pressure gauge are included in the accessory kit
. A discharge line should be installed 6” above
the drain in the event of a pressure relief. The pipe size must be the same size as the relief valve outlet. NEVER BLOCK THE OUTLET
OF THE SAFETY RELIEF VALVE.