Carrier 58ST Installation, Start-Up, Operating And Service And Maintenance Instructions page 21

NOTE: The furnace gas valve inlet pressure tap connection is
suitable to use as test gauge connection providing test pressure
DOES NOT exceed maximum 0.5 psig (14- -in. wc) stated on gas
control valve. (See Fig. 47.)
90° Elbow
2" Nipple
Street Elbow
Gas Valve
Fig. 21 --- Burner and Manifold
Some installations require gas entry on right side of furnace (as
viewed in upflow.) (See Fig. 21.)
Install a sediment trap in riser leading to furnace as shown in Fig
22. Connect a capped nipple into lower end of tee. Capped nipple
should extend below level of furnace gas controls. Place a ground
joint union between furnace gas control valve and exterior
manual equipment gas shutoff valve. A 1/8- -in. NPT plugged
tapping, accessible for test gauge connection, MUST be installed
immediately upstream of gas supply connection to furnace and
downstream of manual equipment shutoff valve.
GAS
SUPPLY
MANUAL
SHUTOFF
VALVE
(REQUIRED
SEDIMENT
TRAP
UNION
Fig. 22 --- Typical Gas Pipe Arrangement
Piping should be pressure and leak tested in accordance with
NFGC in the United States or CAN/CSA- -B149.1- -05 in Canada,
local, and national plumbing and gas codes before the furnace has
been connected. After all connections have been made, purge
lines and check for leakage at furnace prior to operating furnace.
If pressure exceeds 0.5 psig (14- -in. wc), gas supply pipe must be
disconnected from furnace and capped before and during supply
pipe pressure test. If test pressure is equal to or less than 0.5 psig
(14- -in. wc), turn off electric shutoff switch located on furnace gas
control valve and accessible manual equipment shutoff valve
before and during supply pipe pressure test. After all connections
have been made, purge lines and check for leakage at furnace
prior to operating furnace.
A05028
A02327
Fig. 24 --- Field- -Supplied Electrical Box on Furnace Casing
The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.
ELECTRICAL CONNECTIONS
A02035
21
Fig. 23 --- Relocating J- -Box
TWO
A02099
A03221