7
Part Number 550-142-785/0812
GWI
Series 2
Gas-Fired Water Boilers –
Boiler Manual
Perform hydrostatic pressure test
Pressure test boiler before attaching water or gas piping or
electrical supply (except as noted below).
Prepare boiler for test
1. Remove the shipping nipple (from GWI supply tapping) and
remove the boiler relief valve. Temporarily plug the relief valve
tapping with a ¾” NPT pipe plug.
2. Remove 1¼” nipple, reducing tee and drain valve from ac
-
cessory bag. Install in boiler return connection as shown on
in Figure 27, item 3, page 44
. Install circulator on either the
return or supply.
3. Remove 1¼” nipple, 1¼” tee, bushing and pressure/tempera-
ture gauge from accessory bag. Pipe to boiler supply connec
-
tion as shown in Figure 27, item 2, page 44
. (Use pipe dope
sparingly.)
4. Connect a hose to boiler drain valve, the other end connected
to a fresh water supply. Make sure hose can also be used to
drain boiler after test.
5. Connect a nipple and shutoff valve to system supply connec
-
tion on the 1¼” tee. This valve will be used to bleed air during
the fill. (Valve and nipple are not included with boiler.)
6. Connect a nipple and shutoff valve to system return connec
-
tion (at circulator flange if circulator installed on return). This
valve will be used to bleed air during the fill. (Valve and nipple
are not included with boiler.)
Fill and pressure test
1. Open the shutoff valves you installed on supply and return
connections.
Pressure test
2. Slowly open boiler drain valve and fresh water supply to fill
boiler with water.
3. When water flows from shutoff valves, close boiler drain valve.
4. Close shutoff valves.
5. Slowly reopen boiler drain valve until test pressure of not more
than 45 psi is reached on the pressure/temperature gauge.
6. Test at no more than 45 psi for no more than 10 minutes.
Do not leave boiler unattended. A cold water fill could
expand and cause excessive pressure, resulting in
severe personal injury, death or substantial property
damage.
7. Make sure constant gauge pressure has been maintained
throughout test. Check for leaks. Repair if found.
Leaks must be repaired at once. Failure to do so
can damage boiler, resulting in substantial property
damage.
Do not use petroleum-based cleaning or sealing
compounds in boiler system. Severe damage to
boiler will occur, resulting in substantial property
damage.
Drain and remove fittings
1. Disconnect fill water hose from water source.
2. Drain boiler at drain valve or out hose, whichever provides
best access to drain. Remove hose after draining if used to
drain boiler.
3. Remove nipples and valves unless they will remain for use in
the system piping.
4. Remove plug from relief valve tapping. See page 13 to replace
relief valve.
3 Vent installation
The GWI boiler can be vented using one of the following methods:
Use only the vent materials and methods outlined
in this manual. Use of any other materials or meth
-
ods could result in vent failure or flue gas leakage,
causing severe personal injury, death or substantial
property damage.
Chimney draft venting
— Uses the natural draft provided by a vertical vent or chimney.
When vented using chimney draft venting, GWI boilers are rated
as Category I appliances (no pressure in vent and flue gas tem
-
perature hot enough to avoid excessive vent condensation). See
following section for installation procedures.
Chimney draft installations use:
a. Vent connector (single or doublewall) sized to eliminate positive
pressure in vent system. Diameter increases immediately at
boiler. See Figure 3, page 8
for connector sizing.
b. Double-wall metal vent (B-vent) or chimney with liner approved
by the National Fuel Gas Code, ANSI Z223.1–latest edition,
or in Canada B149.1 or B149.2 Installation Code.
Direct exhaust — vertical or sidewall
— Vent pipe is pressurized and terminated vertically through the
roof or through a side wall. When vented as direct exhaust, GWI
boilers are rated as Category III appliance (positive pressure in
the vent and flue gas temperature hot enough to avoid excessive
vent condensation).
You must use only the vent materials listed in this manual. See
pages 8 through 12
for installation procedures.
Direct exhaust installations use:
a. Vent materials specified in this manual.
b. Vent termination through outside wall, roof or unused chimney.
(Tight chimney areas will make vent joint construction very
difficult.)
GWI venting options
2 Prepare boiler
continued
