Laars MIGHTY THERM2, Assembly, Installation And Operation Instructions

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Mighty Therm
2
Page 13
galvanized pipe and elbows to allow the open end to face
down aside the boiler. This is available as a Commercial
Kit from the manufacturer.
Part numbers for the low profile terminals to cover the
vent and combustion air openings are shown in Table 6.
SECTION 3.
Gas Supply and Piping
3.1 Gas Supply and Piping
Gas piping should be supported by suitable hangers
or floor stands, not by the appliance.
Mighty Therm2’s gas train allows the user to pipe
the gas from either the right side or the left side of the
unit. As shipped, the right side of the gas train is capped
off, and there is a manual valve on the left side. If
desired, the manual valve on the left side of the gas train
may be moved to the right side, and the cap on the right
side may be moved to the left.
Review the following instructions before
proceeding with the installation.
1. Verify that the appliance is fitted for the proper type
of gas by checking the rating plate. Mighty Therm2
appliances are equipped to operate at elevations up
to 10,000 feet (3050m). Mighty Therm2 appliances
may be adjusted to operate properly at altitudes
above 2500 feet (see Section 6.6.2 ) and the input
will be reduced if the heating value of the gas
supply is below sea level values.
2. The maximum inlet gas pressure must not exceed
13" W.C (3.2kPa). The minimum inlet gas pressure
is 5" W.C. (1.2kPa).
3. Refer to Table 7 , size supply.
4. Run gas supply line in accordance with all
applicable codes.
5. Locate and install manual shutoff valves in
accordance with state and local requirements.
6. A sediment trap must be provided upstream of the
gas controls.
7. All threaded joints should be coated with piping
compound resistant to action of liquefied petroleum
gas.
8. The appliance and its individual shutoff valve must
be disconnected from the gas supply piping during
any pressure testing of that system at test pressures
in excess of 1/2 PSIG (3.45kpa).
9. The unit 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).
10. The appliance and its gas connection must be leak
tested before placing it in operation.
11. Purge all air from gas lines.
WARNING
Do not use open flame to check for leaks. An open
flame could lead to explosion, which could result in
property damage, serious injury or death.
NOTE : The Mighty Therm2 appliance and all other gas
appliances sharing the gas supply line must be firing at
maximum capacity to properly measure the inlet supply
pressure. The pressure can be measured at the supply
pressure port on the gas valve. Low gas pressure could
be an indication of an undersized gas meter, undersized
gas supply lines and/or an obstructed gas supply line.
Unit
20°F 25°F 30°F 35°F
Size flow H/L flow H/L flow H/L flow H/L
gpm feet gpm feet gpm feet gpm feet
500 43 1.7 34 1.1 28 0.9 24 0.7
750 64 3.3 51 2.3 43 1.7 36 1.2
1000 85 5.0 68 3.6 57 3.1 49 2.2
1250 106 8.1 85 6.1 71 4.7 61 3.4
1500 128 10.0 102 7.2 85 5.5 73 4.2
1750 N/R N/R 119 10.5 99 8.4 85 5.8
2000 N/R N/R 136 12.5 113 10.4 97 8.3
Metric Equivalent
Unit
11°C 14°C 17°C 19°C
Size flow H/L flow H/L flow H/L flow H/L
lpm m lpm m lpm m lpm m
500 161 0.5 129 0.3 107 0.3 92 0.2
750 241 1.0 193 0.7 161 0.5 138 0.4
1000 321 1.5 257 1.1 214 0.9 184 0.7
1250 401 2.5 322 1.9 269 1.4 231 1.0
1500 483 3.0 386 2.2 322 1.7 276 1.3
1750 N/R N/R 451 3.2 375 2.6 322 1.8
2000 N/R N/R 515 3.8 429 3.2 368 2.5
Notes: gpm = gallons per minute, lpm = liters per minute,
H/L = headloss, ft = headloss in feet, m = headloss in meters.
Maximum temperature rise is 35°F (19°C), as shown. Headloss is
for boiler’s heat exchanger only. N/R = not recommended.
Table 8. Water Flow Requirements — MT2H.
Figure 5. Typical Gas Train Configuration.