LAARS U.H.E. - Installation Manual - Manual (Page 34)

CAUTION
The water heater and individual shutoff valve must be disconnected from the gas supply piping system during any
pressure testing of the system at test pressures in excess of ½ psi (3.5 kPa). The water heater must be isolated from
the gas supply piping system by closing its manual shutoff valve during any pressure testing of the gas supply
system at test pressures equal to or less than ½ psi (3.5 kPa). The supply line must be capped when not connected to
the water heater.
If copper supply lines are used, they must be internally tinned and certified for gas service.
Figure 24. Drip Leg
The gas supply lines must meet all requirements of the National Fuel Gas Code ANSI Z223.1 (Latest Edition), or in
Canada CAN/CGA B149.1 Natural Gas Installation Code (Latest Edition) or CAN/CGA B149.2 Propane Installation
Code (Latest Edition).
GAS METER SIZE – NATURAL GASES ONLY
Be sure that the gas meter has sufficient capacity to supply the full rated gas input of the water heater as well as the
requirements of all other gas fired equipment supplied by the meter. If the gas meter is too small, ask the gas company
to install a larger meter having adequate capacity.
GAS PRESSURE REGULATION
Main line gas pressure to the water heater should be between a maximum 14.0 inch W.C. and a minimum supply
pressure as shown on the rating plate. The inlet gas pressure must not exceed the maximum value. In some
installations, a regulator sized for the input rating of the water heater will need to be installed just ahead of the inlet gas
connection to the water heater to reduce excess gas pressure or surges in gas pressure.
BEFORE PLACING THE WATER HEATER IN OPERATION, CHECK FOR GAS LEAKAGE. USE SOAP AND
WATER SOLUTION OR OTHER MATERIAL ACCEPTABLE FOR THE PURPOSE OF LOCATING GAS LEAKS.
WARNING
DO NOT USE MATCHES, CANDLES, FLAME OR OTHER SOURCES OF IGNITION FOR THIS
PURPOSE.
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