State GPG 81 370NEA - Manual (Page 19)

19
Where an existing chimney or vent is to be used, be sure
that the chimney or vent has adequate capacity for the
number and sizes of gas appliances being vented through
it. Inspect the chimney or vent and remove all soot or other
obstructions which will retard free draft.
Vent connectors making horizontal runs must have a minimum
upward slope toward the chimney or vent of 1/4 inch per foot.
Vent connector length should be kept as short as possible.
Be sure that the vent pipe does not extend beyond the inside
wall of a chimney.
In venting systems where a continuous or intermittent
back (positive) draft is found to exist, the cause must
be determined and corrected. In some cases, a special
vent cap may be required. Do not install this unit on the
positive draft side of a venting system being served by a
power exhauster.
water heater installation
Vent connection
Vent connections must be made to an adequate stack
or chimney. refer to the National Fuel Gas Code (current
edition) or to the vent pipe manufacturer’s gas vent and
chimney sizing table to properly design and size the venting
system. refer to Table 6 for the vent pipe size required for
installation to the barometric draft control assembly outlet.
table 6. barometric draft control
assembly outlet siZe
model
draft control
outlet diameter
GPG 81-140
GPG 81-199
GPG 81-270
GPG 81-370
6”
6”
8”
8”
water piping diagrams
This manual provides detailed water piping diagrams for typical
methods of application for the water heaters, see Water Piping
Diagrams beginning on page 35.
The water heater may be installed by itself, or with a separate
storage tank. When used with a separate storage tank, the
circulation may be either by gravity or by means of circulating
pump. Adjust flow by throttling a full port ball valve installed in the
circulating line on the outlet side of the pump. Never throttle flow
on the suction side of a pump. See the Water Piping Diagrams
beginning on page 35.
note: In addition to the factory installed Temperature-Pressure
relief Valve (T&P valve) on the water heater, each remote
storage tank that may be installed and piped to a water heating
appliance must also have its own properly sized, rated and
approved Temperature-Pressure relief Valve installed.
Call the toll free technical support phone number listed on the
back cover of this manual for further assistance in sizing a T&P
valve for remote storage tanks.
t&p ValVe discharge pipe
Explosion Hazard
Temperature-Pressure Relief Valve
must comply with ANSI Z21.22-
CSA 4.4 and ASME code.
Properly sized temperature-
pressure relief valve must be
installed in opening provided.
Can result in overheating and
excessive tank pressure.
Can cause serious injury or death.
water line connections
The water piping installation must conform to these instructions
and to all local code authority having jurisdiction. Good practice
requires that all heavy piping be supported.
read and observe all requirements in the following sections
before installation of the water piping begins:
1. Water Temperature Control and mixing Valves on page 13.
2. Dishwashing machines on page 14.
3. Temperature-Pressure relief Valve on page 14-15.
4. Closed Systems and Thermal expansion on page 14.
5. For multiple water heater installations see Water Piping
Diagrams beginning on page 35.
water (potable) heating and space heating
1. All piping components connected to this unit for space
heating applications shall be suitable for use with potable
water.
2. Toxic chemicals, such as those used for boiler treatment,
shall NeVer be introduced into this system.
3. This unit may NeVer be connected to any existing heating
system or component(s) previously used with a non-potable
water heating appliance.
4. When the system requires water for space heating at
temperatures higher than required for domestic water
purposes, a tempering valve must be installed. Please
refer to installation diagrams beginning on page 35 of this
manual for suggested piping arrangements.
5. These water heaters cannot be used in space heating
applications only
thermometers (not supplied)
Thermometers should be obtained and field installed as shown
in the installation diagrams.
Thermometers are installed in the system as a means of
detecting the temperature of the outlet water supply.