Typical Piping Connections
Figure 5:
Connections
A = Shutoff Cock (ball valve)
B = Union - Furnished .
C = Gas Pipe - Routed in through front
D = Gas Pipe - Routed in through curb
E = Factory Piped Gas Trains
F = Pilot Gas Tubing
Gas Piping
(Models 150 through 200)
The gas piping cannot be routed up to the burner from within
the curb on Models 150 through 200 . Gas piping must be
routed across the roof to under the burner vestibule, or a pitch
pocket can be provided there . The installer must cut a hole in
the bottom panel of the overhanging burner vestibule through
which to route the gas line up to the burner gas train . The
bottom panel of the vestibule is at approximately the same
elevation as the top of the curb .
Gas Piping within the Vestibule
The gas piping layout within the vestibule will vary according
to the complexity and size of the gas train relative to the
available room within the vestibule . As an example, a gas
train with a high pressure regulator and an extra safety
shutoff valve (when required for IRI, etc.) will require careful
use of the available space . The examples shown in
indicate typical piping layouts .
Field Gas Piping Required
The gas train components have all been factory installed and
require only a connection to the supply gas line . The manual
shutoff valve is located within the burner vestibule. If local
codes require a manual shutoff valve that is accessible from
outside the unit, that valve must be relocated or an additional
valve added . In locating such a valve, it is to be readily
accessible and located such that no obstructions interfere with
operation of the handle .
The furnace and manual furnace shutoff valve must be
disconnected from the gas supply piping system during any
pressure testing of that system at test pressure in excess of
½ psi (3 .5 kPa) .
The furnace must be isolated from the gas supply piping
system by closing the manual furnace shutoff valve during
any pressure testing of the gas supply piping system at test
pressures equal to or less than of ½ psi (3 .5 kPa) .
D
C
With Shutoff Cock
In Front
D
C
A
With Shutoff Cock
Folded back
A
B
E
F
IM 684-6 • ROOFTOP SYSTEMS 8
www .DaikinApplied .com
Installation
