Laars MagnaTherm HTD Series, Инструкция по установке и эксплуатации

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LAARS Heating Systems
Page 20
NOTE: This unit and all other gas units 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. The units may be equipped with low
and high pressure gas switches that are integrally
vent limited. These types of devices do not require
venting to atmosphere.
NOTE: After placing the boiler in operation, the
ignition system safety shutoff device must be tested.
See 10.A on page 102
SECTION 3 Gas supply and Piping
3.A Gas Supply and Piping
All Installations must conform to the National Fuel
Gas Code ANSI Z223.1/NFPA54, and/or local codes.
In Canada, the installation must conform to the latest
edition of CSA B149.1 Natural Gas and Propane Gas
Installation Code, and/or local codes. Gas piping should
be supported by suitable hangers or floor stands, not the
unit.
Review the following instructions before proceeding with
the installation.
1. Verify that the unit is fitted for the proper type of gas by
checking the rating plate.
NOTE: This unit is equipped to operate at elevations
up to 2000 feet (610m). However, the unit will function
properly without the use of high altitude modification at
elevations up to 10,000 feet (3050 m).
For elevations above 2000 ft (600 m), the input gas
rating shall be reduced at a rate of 4 percent for each
1000 ft (300 m) above sea level. This must be considered
before selecting the equipment size.
2. The gas pressure settings must match fuel type as
shown in Table 11.
3. Table 12 and Table 13 on page 21 offer some gas
pipe sizing information. Refer to the applicable gas
code for more detailed sizing information.
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 liquified petroleum gas.
8. The unit 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 unit and its gas connection must be leak tested
before placing it in operation.
11. Purge all air from gas lines
Table 11. Gas Pressure
Natural Gas LP (propane)
Min 4.0 IN - W.C. 8.0 IN - W.C.
Max 10.5 IN - W.C. 14.0 IN - W.C.
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.
WARNING
If an inline high gas pressure regulator is used, it
must be of the lockup type and located a minimum
of 10 feet from the unit. Failure to do so may result in
insufficient gas volume supplied to the unit.