Connecting The Water Supply - Navien NPN Installation & Operation Manual

3.4 Connecting the Water Supply

The water fittings on the water heater are
If the installation site only has
throughout, it is not necessary to upsize the water
lines to / in.
3
4
When connecting the water supply, follow these
guidelines:
Use only pipes, fittings, valves, and other
●
components, such as solder, that are approved for
use in potable water systems.
Tighten the water heater connection valves with
●
care to avoid damage.
We recommend using unions and manual shut-
●
off valves on the cold water inlet and DHW outlet.
Strive to make the hot water piping system as
●
short as possible, to deliver hot water to the
fixtures more quickly.
To conserve water and energy, insulate all water
●
piping—especially the hot water line. Never
cover the drain or pressure relief valve. If the
water heater is installed in a closed water supply
system, such as one having a backflow preventer
in the cold water supply line, means shall be
provided to control thermal expansion. Contact
the water supplier or local plumbing inspector for
information about how to control this situation.
After installing the water heater, clean the inlet
●
water filter that is located inside the cold water
inlet, and then test the water heater for proper
flow and inspect for leaks. Instruct the water
heater owner that the filter must be cleaned
periodically to maintain proper water flow.
/ in.
3
4
/ in plumbing
1
2
Union
Pressure
Relief Valve
Hot Water
Supply
Cold Water
Supply
* The illustration above provides a typical water piping
installation example and is for reference only.
3.4.1 Using the Water Heater for
Combination Water Heating and Space
Heating
When using the water heater for both water
(potable) heating and space heating, follow these
guidelines:
Ensure that all piping and components connected
●
the water heater are suitable for potable water
applications.
Do not introduce toxic chemicals, such as water
●
treatments, into the potable water.
On Combi applications, circulators suitable for
●
DHW applications must be used.
Do not connect the water heater to any heating
●
systems or components that have been
previously used with non-potable water heaters.
If the system requires varying temperatures
●
for water—for example, hotter water for space
heating than for other uses—install a mixing
valve to temper the water and reduce the
potential for scalding.
Do not use the water heater for space heating
●
only.
Make sure circulator flow rate through the Water
●
Heater does not exceed 4 GPM.
Full port
Gas Valve
Shutoff
Valve
Gas
Supply
Installing the Water Heater 25