Daikin DRG0361DL00001S, Инструкция по эксплуатации

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SYSTEM OPERATION
A manual gas shut off valve must be field installed external
to the roof top unit. In addition, a drip leg must be
installed near the inlet connection. A ground joint union
connection is required between the external shut off valve
and the unit connection to the gas valve to permit removal
of the burner assembly for servicing.
1. Route gas piping to unit so that it does not interfere
with the removal of access panels. Support and align
piping to prevent strains or misalignment of the
manifold assembly.
2. All units are furnished with standard female 1/2” NPT
pipe connections. The size of the gas supply piping
to the unit must be based on length of run, number
of units on the system, gas characteristics, BTU
requirement and available supply pressure. All piping
must be done in accordance with local codes or, in
the absence of local codes, with the latest edition of
the National Fuel Gas Code
ANSI Z223.1/NFPA 54.
NOTE: The gas connection size at the unit does NOT
establish the size of the supply line.
3. These units are designed for either natural or
propane (LP) gas and are specifically constructed at
the factory for only one of these fuels. The fuels are
NOT interchangeable. However, the furnace can be
converted in the field from natural gas to LP gas with
the appropriate factory kit (see unit Technical Manual
for the appropriate kit). Only a qualified contractor,
experienced with natural and propane gas systems,
should attempt conversion. Kit instructions must
be followed closely to assure safe and reliable unit
operation.
4. With all units on a common line operating under
full fire, natural gas main supply pressure should
be adjusted to approximately 7.0” w.c., measured
at the unit gas valve. If the gas pressure at the unit
is greater than 10.0” w.c., the contractor must
furnish and install an external type positive shut off
service pressure regulator. The unit will not function
satisfactorily if supply gas pressure is less than 5.0”
w.c. or greater than 10.0” w.c..
NOTE: A minimum horizontal distance of 48” between
the regulator and the furnace flue discharge is required.
5. With all units on a common line operating under
full LP gas main supply pressure should be at least
11.0” w.c. and must be no greater than 13.0” w.c.,
measured at the unit gas valve. Unit will not function
satisfactorily if supply gas pressure is less than 11.0”
w.c. or greater than 13.0” w.c..
6. All pipe connections should be sealed with a pipe
thread compound, which is resistant to the fuel used
with the furnace. A soapy water solution should be
used to check all joints for leaks. A tap is located
on the entering side of the gas valve for test gauge
connection to measure supply (main) gas pressure.
Another tap is provided on the manifold side of the
gas valve for checking manifold pressure.
WARNING
This unit and its individual shutoff valve must be
DISCONNECTED from the gas supply system during any
pressure testing of that system at test pressures in excess
of ½ PSIG (13.8” w.c.).
CAUTION
This unit must be ISOLATED from the gas supply piping
system by closing its individual manual shutoff valve
during any pressure testing equal to or less than ½
PSIG.
7. There must be no obstruction to prevent the flow
of combustion and ventilating air. A vent stack is not
required and must never be used. The power venter
will supply an adequate amount of combustion air
as long as the air passageways are kept free of any
obstructions and the recommended external unit
clearances are maintained.
CIRCULATING AIR AND FILTERS
Ductwork
The supply duct from the unit through a wall may be
installed without clearance. However, minimum unit
clearances must be maintained (see “Clearances” section).
The supply duct should be provided with an access panel
large enough to inspect the air chamber downstream of
the heat exchanger. A cover should be tightly attached to
prevent air leaks.
Ductwork dimensions are shown in the roof curb
installation manual.
If desired, supply and return duct connections to the unit
may be made with flexible connections to reduce possible
unit operating sound transmission.