Demand Duo
™
H
-
Series Installation and Operation Manual
43
1.
Install a manual gas control valve in the gas
supply line to the water heater. A union can
be used on the connection above the shut off
valve for the future servicing or disconnection
of the water heater (Figure 45 on the follow-
ing page).
2.
Check the type of gas and gas supply pres-
sure before connecting the water heater. If
the water heater is not of the gas type that
the building is supplied with, DO NOT con-
nect the water heater. Contact the dealer for
the proper water heater to match the gas
type.
3.
Check the gas supply pressure immediately
upstream at a location provided by the gas
company. Supplied gas pressure must be
within the limits shown in the Section
“3.2
Specifications
”
with all gas appliances oper-
ating.
•
A licensed professional must install the gas
supply.
•
Turn off 120V power supply.
•
Turn off the gas.
•
Gas is flammable. Do not smoke or provide
other ignition sources while working with
gas.
•
Do not turn on the water heater or gas until
all fumes are gone.
WARNING
To connect the gas supply, follow the instructions
below:
3/4 in. MNPT Gas Connection
on Bottom of Water Heater
Topics in this section
•
Connect the Gas Supply
•
Connect Electricity
•
Pump Controller
Figure 45
Figure 46
The gas swivel and gas
flex line can move in
multiple directions for
installation.