The installation of this oven must be done by a qualified
installer familiar with the local codes and regulations governing
the installation of commercial gas appliances.
The installation must be done in accordance with local codes,
and in the absence of local codes, with the National Fuel Gas Code
ANSI Z223.1 (latest edition). In Canada, the appropriate code is
the Natural Gas Installation Code, CAN/CGA-B149.1 or the
Propane Installation Code, CAN/CGA-B.
GAS TYPE & PRESSURE
Check the oven nameplate information to determine the type of
gas the Combitherm Gas Oven/Steamer was manufactured for
(natural or propane) and make sure the gas supply matches the
nameplate information.
Check the nameplate to determine the gas manifold pressure for
the oven. The minimum supply pressure to the oven must exceed
this value by at least 1" w.c. It is recommended that the supply
pressure be between 5" w.c. and 14" w.c. for natural gas, and 11"
w.c. and 14" w.c. for propane.
An alternate gas supply inlet may be
required for installation sites at elevations of 3,000 feet (914m) above sea
level. Please check with factory.
Should conversion to the opposite fuel be desired, conversion
parts must be ordered from the factory.
Conversion must be done by
a qualified service person only.
Always remember to reflect the
conversion on the oven's nameplate.
GAS CONNECTION
The minimum size of the gas piping or flexible connector is 1/2"
except for the Model 20•20 which is 3/4". For long runs of gas
piping, the pipe diameter must conform to the tables in the
National Fuel Gas Code, ANSI/NFPA Z223.1.
A listed gas shut-off valve must be installed upstream of the
appliance for shutting off the gas supply during servicing. This
valve should be installed so that it is accessible with the appliance
in its normally installed position.
If the oven or its stand is supplied with casters – the installation
must be done with a flexible connector that complies with the
Standard for Connectors for Movable Gas Appliances, ANSI
Z21.69; or in Canada, Connectors for Movable Gas Appliances,
CAN/CGA-6.16-M87. When using a flexible connector, a quick
disconnect device must also be used that complies with the
Standard for Quick-Disconnect Devices for Gas Fuels, ANSI
Z21.41; or in Canada, Quick Disconnect Devices for Use with Gas
Fuels, CAN1-6.9.
When a quick disconnect device and flexible connector are used,
a restraining device must be used which will limit the movement
of the appliance to prevent damage to the connector or quick
disconnect. An example of such a system is to use 2000 pound test
stainless steel cable attached to a structural member of the kitchen
wall behind the oven. The attachment means should have a quick
connect snap such that it can be disconnected when the appliance
needs to be moved away from the wall. The other end of the cable
should be permanently attached to the rear
frame of the oven. The length of the cable
should be such that no strain is ever placed
upon the flexible gas connector if the
appliance is accidentally moved without
first disconnecting the gas connector.
The flexible connector should be routed
so that it forms a downward "U" loop
between the building gas supply and
where it attaches to the rear of the oven.
The routing of the flexible connector must not be done under
the oven. The temperatures during operation are too hot for safe
operation. Gas piping should be installed from the point of gas
connection at the bottom, front of the oven to the back of
the oven where the flexible connector may be used. See
the illustration for the recommended procedure.
LEAK
TESTING
If a pressure leak test above 1/2 psi is to be done on the build-
ing supply gas piping, the shut-off gas valve and oven inlet gas
supply line must be disconnected from the building supply piping
before
conducting the pressure test.
Failure to do so may result in
damage to the manual gas valve and/or gas components in the oven.
If any gas leak tests are to be conducted at pressures equal to or
below 1/2 psi, the manual gas shut-off valve upstream of the oven
must be turned off before conducting the tests.
Leak testing of the internal oven piping system was conducted
before shipping the oven from the factory. If additional testing is
needed, it should only be conducted at normal gas supply
pressures. If the testing is performed using combustible gas in the
piping, the leak checking should be done with a soap solution
(bubble checking).
NEVER CHECK FOR LEAKS USING AN OPEN FLAME.
The use of electronic combustible gas leak detectors is
helpful, but they can be oversensitive.
They may find leaks that are not visible
when checking with a liquid solution,
and therefore, present no hazard.
When starting unit after initial installation, the gas
lines must be free of air. It may take up to 30 minutes to do this. If, after
this time there is no pilot, call for factory assistance.
FUEL INTERLOCK SYSTEM
Local codes may require that the fuel supply to the oven be
interlocked to the ventilation hood. If that is the case, a separate
electrically operated gas valve must be installed in the gas line.
The selection of the valve will be up to the installer, but the valve
should be recognized by the authority having jurisdiction.
The oven is not for direct connection to a chimney vent system
or for direct connection to a horizontal exhaust system. The oven
must be installed under a ventilation hood listed to ANSI/UL 705
(latest edition), and the installation must be done in accordance
with the ANSI/NFPA 96-1987, Standard for Ventilation Control
and Fire Protection of Commercial Cooking Operations.
The oven is supplied with a flue diverter that must be installed
on the oven prior to installation.
See Assembly at the front of this
manual.
The operators of the oven should be
instructed not to place any material on top of the
oven that would obstruct the flow of flue products
out the opening. They should also be instructed that
the flue gases are hot, and that any material or items
they place on top of, or in front of the flue defector
could be damaged or cause fire hazard.
T I O N
G U I D E L I N E S
Operation and Care Manual #6011 • 3
1.11 - GAS CONNECTIONS
1.12 - GAS EXHAUST
I n s t a l l a t i o n • S e c t i o n 1
The gas piping must never be run under the
burner––there is danger of overheating.
