LAARS HWG-M2-250 - Installation, Operation and Maintenance Instructions User Manual
Page 6
Page 6
LAARS Heating Systems
Length
Capacity of Pipe in MBTU/h
of
(.6 Specific Gravity)
Pipe
3/4"
1"
1-1/4"
10'
278
520
1,050
20'
190
350
730
30'
152
285
590
40'
130
245
500
50'
115
215
440
75'
93
175
360
100'
79
150
305
150'
64
120
250
Additional length to be added for each tee or bend:
1.7'
2.2'
2.7'
piping during any pressure testing of that system
at test pressures in excess of 1/2 psig (3.45kpa).
It must be isolated from the gas supply system
by closing its individual manual shutoff valve
during any pressure testing of the gas supply
piping system at test pressures equal to or less
than 1/2 PSIG (3.45kpa).
Failure to do so will possibly result in damage to
the gas control system.
8.
The 9600 HWG Water Heater and its gas
connections must be leak tested before placing
the unit in operation.
9.
Purge all air from gas lines.
3.3 Connecting Water System Piping,
Fittings & Accessories
Installing tank & piping
The 9600 HWG can be used with several
different types of readily available storage tanks. A
bronze circulating pump is built into the appliance.
The pump draws water from the storage tank and
pumps the water through the heater and back into
the tank.
Position the storage tank(s).
At the previously selected locations, position the
storage tank(s). Use Table 3 to determine the pipe size
necessary to provide adequate flow between the 9600
HWG and the tank(s).
Hot water outlet piping, fittings, and accessories.
1.
Begin piping to the tank from the hot water
outlet at the top of the 9600 HWG cabinet.
2.
Pipe the outlet from the relief valve (located on
top of the unit) such that any discharge from the
relief valve will be conducted to a suitable place
for disposal when relief occurs. Do not reduce
line size or install any valves in this line. The
line must be installed to allow complete drainage
of both the valve and the line.
3.
Install a shut off valve in the piping between the
thermometer fitting and the tank.
The following steps are recommended for vent
installation:
1.
Obtain the necessary 3" or 4" diameter plastic
piping and fittings as determined beforehand.
2.
Position unit at previously selected location.
3.
Unpack vent terminals and vent terminal backing
plates.
4.
Cut holes in outside wall for vent terminals in
the previously selected locations.
5.
Mount the vent terminals’ backing plates.
6.
Fit all of the vent pipes together without
cementing. Make sure that there are no water
traps and that any pitch is inclined back towards
the boiler.
7.
Make sure that the flexible vent connections at
the unit fit properly.
8.
Begin cementing the intake and exhaust pipes,
start at the vent terminals and work back towards
the appliance. Note that the intake terminal is a
90 degree elbow fitting that is designed to face
down.
9.
Support both intake and exhaust pipes with
hangers.
DO NOT RELY ON 9600 HWG TO SUPPORT
PIPES.
Horizontal runs must be supported adjacent to
each fitting and at 5ft. intervals between fittings.
ABS pipe must be supported at 3ft. intervals.
10. Tighten the flexible couplings to connect the
water heater to the vent pipes.
3.2 Connecting Gas to the 9600 HWG
Water Heater
1.
The water heater requires gas at an inlet gas
pressure of at least 4" WC and no greater than
13" WC. Check with your local gas utility or
supplier for availability of these delivery
pressures.
2.
Referring to TABLE 2, size supply piping to
keep flow capacity to the unit above 250 cubic
feet per hour (CFH) per unit installed.
3.
Run gas supply line in accordance with all
applicable codes.
4.
Locate and install manual shutoff valves in
accordance with state and local requirements.
5.
Install drip leg and ground joint union
(see Figure 5).
6.
All threaded joints should be coated with piping
compound resistant to action of liquefied
petroleum gas.
7.
The 9600 HWG unit and its individual shutoff
valve must be disconnected from the gas supply
Table 2. Gas supply piping.