Owner`s manual

P40U-F / P40U-IF I&O Manual

IM101220

RD: JAN 2014

RL: 4A

DO NOT use pressure greater than 1/2 psig to pressure check the heater. During

any pressure testing of the gas piping system each heater must be isolated from

the piping system by closing its individual manual shut off valve (field supplied) .

IMPORTANT: Minimum supply line pressure at the inlet to the heater regula-

tor must not be lower than 5.0 inches of water column pressure for natural gas. The

supply gas pressure must be checked with all heaters in operation.

Installation of a gas line (trap) “drip leg” is required at the inlet connection tee following the

pipe drop to the heater. Failure to provide a “drip leg” could result in condensation and foreign

matter passing into the gas valve. Failure to install a “drip leg” in the gas line can cause prop-

erty damage, injury or death and will void the heater warranty.

TABLE 4

GAS TYPE

LINE PRESSURE

INCHES WATER COLUMN

MANIFOLD PRESSURE

(tap at gas valve outlet)

INCHES WATER COLUMN

MINIMUM MAXIMUM

Natural Gas 5.0 14.0 3.5

LP Gas 11.0 14.0 10.0

ORIENTATION OF FLEXIBLE GAS CONNECTOR

The flexible gas connector MUST be installed in the orientation shown below as required by

national installation codes and by the certification standard of this heater. This orientation pro-

tects the flexible gas connector from damage due to movement during heater expansion.

It is the responsibility of the installer to ensure correct installation of the flexible gas connector.

FIGURE 12

NOTE: Access to the manifold pressure test port is located on the top of the valve. A 3/16" Al-

len Key is required. A manometer should be used to check the manifold pressure. Gauges

which measure in ounces or PSI are not accurate enough to measure or set the pressure.