TriangleTube Marquis TWH180, Installation Manual

Page: 20 / 39

Water Piping
17
See below for location of inlet and manifold gas pressure
ports on the gas valve.
The minimum and maximum inlet gas pressure are:
The appliance and its individual shutoff valve must be
disconnected from the gas supply piping system during
any pressure testing of that system at test pressures in
excess of ½ psi (3.5 k Pa). The appliance must be iso-
lated from the gas supply piping system by closing its
individual manual shutoff valve during any pressure test-
ing of the gas supply piping system at test pressures
equal to or less than ½ psi (3.5 kPa).
Plumbing and Water Connection Guidelines.
•
Use at least the MINIMUM pipe size of 3/4” for all
Water Heater loop piping
- The pipe must be cleaned and without any blemish.
- Do not apply torch heat within 12˝ of the bottom con-
nections of the unit.
- The pipe size used for the inlet water should be the
same size used for the outlet water.
- The size of the hot water pipe should be a minimum
3/4˝ diameter.
- Isolation valves must be used.
- ACV-Triangle Tube highly recommends installation
of tankless water heater isolation valves with flush-
ing ports for routine maintenance.
- All piping should be insulated.
Backflow Preventer
- Apply a backflow preventer valve in the make-up
water supply (water Inlet) to the unit as required by
local codes.
CAUTION
Manifold
Pressure
Port
Inlet Gas
Pressure
Port
Natural Gas LP Gas
Maximum
Pressure
10.5” WC
Maximum
Pressure
13” WC
Minimum
Pressure
3.5” WC
Minimum
Pressure
8.0” WC
3/4" PIPE (D W INLET )
3/4" PIPE (DH
H
W OUTLET)
3/4" PIPE (GAS INLET ))
Isolation valve
Backflow preventer
Pressure relief valve
Ball valve
Marquis Manual_61515_Water Heater 7/1/15 1:58 PM Page 20