Installation, Before leaving the installation, For high gas pressure installations – Fulton Pulse DWH (PDWH) Domestic Water Heater User Manual

Page 27

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Figure 16. Replace the plug with a

1

/

4

N.P.T. to

1

/

4

" compression (or flare)

adaptor and a short piece of tubing.
Connect one piece of rubber hose from
tubing to a manometer. Open the gas
shutoff valve (gas cock) and turn on water
heater. The following pressures are
for reference only. Depending on the
calorific value of the gas, and
length of intake and vent piping,
the actual pressure can be signifi-
cantly higher or lower.

Pressure for Natural gas should
measure 1 to 3" WC at the last elbow on
the gas train at high fire, or full rate on
on/off units. For more specific
information, consult the test fire report
which is included in the User Manual.
There should be 7" WC at the inlet of
the train.
Pressure for propane should be
11" WC at inlet to the gas train.

To Correct Input—Adjust
Gas Pressure Regulator

Turn water heater off and remove cap
from regulator. Figure 17 Turn adjusting
screw clockwise to increase gas flow
Turn adjusting screw counter clockwise
to decrease gas flow.
Always replace cap before turning on
water heater. Vent must terminate
outdoors. A flow restricting bleed valve
shall not be used.

For High Gas Pressure
Installations

In high gas pressure areas, it is good
practice to step the pressure down as
described below.

1. Locate the stepdown regulator as far
away from the pulse water heater as
possible.
2. When stepping down from more than
2 psig to 7" WC, the stepdown should
be done in two steps:
a) Reduce the pressure to 2 psig.
b) Reduce the pressure from 2 psig to
7" WC
3. The preferred regulator for this
application is the Fisher S Series with
lock up capability.
4. Consult your Authorized Fulton
Representative for selection.

This recommendation is made to avoid
the regulators chattering. It is also
recommended to avoid high lockup
pressures which can cause light off
reliability problems.

Regulators, other than specified, may
be acceptable, but it has been our
experience that the above listed
regulators operate the most
satisfactorily.

To Check for High Gas
Pressure

1. The water heater and its individual
shut-off valve must be disconnected
from the gas supply piping system
during any pressure testing of that
system at test pressures in excess of

1

/

2

psig (3.5 kPa).
2. Turn off water heater and turn off gas
supply to manual gas shutoff valve.
Remove the pressure test plug on
manual shutoff gas valve. Replace
with a

1

/

4"

" NPT to

1

/

4

" compression

(or flange) adaptor and a short piece of
tubing. Connect a piece of rubber
hose from tubing to one side of
manometer.
3. Open gas supply to manual gas
shutoff valve and turn on water heater.
After combustion starts, manometer
should read 7" WC (178mm) minimum
for natural gas and 1” WC (25mm)
minimum for propane.
4. If reading exceeds 7.0" WC.
(178mm) install regulator upstream
of gas valve to reduce pressure.

Check all controls to insure they are
operating properly. Cycle water heater
several times by raising and lowering
operating temperature on the thermostat.

Make sure installation complies with
all applicable codes.

NOTE

It is recommended that an autho-
rized Fulton Pulse start up agent or
your gas utility make any required
gas input adjustments.

Figure 17

Before Leaving The Installation

25-PDWH

Figure 16

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ON

Installation

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