
13
ENGLISH
C. Preparation for Use with Various Gases
Before proceeding to set up the oven for a specific gas, check
that the main gas supp y va ve and the circuit breaker/fused
disconnect are in the OFF ("O") position.
The main and pi ot orifices must match the sizes shown in the
Gas Orifices and Pressure Specifications tab e, near the
beginning of this Section. If necessary, rep ace the orifices.
Refer to Part D, Rep acing the Gas Orifices.
The orifice (manifo d) pressure shou d be adjusted to the va ue
shown in the Gas Orifices and Pressure Specifications tab e for
the specific gas type and ocation.
1. For Use with Natural Gas
The actua heat input to the oven must match the rated heat
input. The input to the burner can be determined using the
orifice (manifo d) pressure data or by the vo ume supp ied
using the gas meter. Both of these procedures are
described in Part F, Adjusting the Orifice (Manifo d) Pressure
and Heat Input.
If the measured input does not correspond with the rated
input (shown in the Gas Orifices and Pressure Specifications
tab e), check first that the correct orifices are insta ed. If the
orifices are correct, check and correct the supp y and orifice
pressures to obtain the correct input based on the gas
meter reading.
2. For Use with Liquid Propane (LP) Gas
When using iquid gas, the converter in the mu tifunction
gas va ve must be removed, and then rep aced INVERTED
from its former position. See Figure 2-16. Inverting the
converter wi disab e the governor. This step is on y
required if the supp y pressure is be ow 50mbar.
D. Replacing the Gas Orifices (if so required)
1. Replacing the Main Orifice
a. Check that the main gas supp y va ve and the circuit
breaker/fused disconnect are in the OFF ("O") position.
b. Open the union in the gas supp y ine. The union is
shown in Figure 2-16, on the previous page.
c. Refer to Figure 2-17. Unscrew the four hex screws that
ho d the venturi mounting p ate to the front of the
burner. Remove the gas train/venturi assemb y from
the oven.
d. Remove the two 1/2" nuts that secure the gas train to
the venturi mounting p ate.
e. Remove the main orifice using an 11/16" wrench.
f. Insta the new orifice.
2. Replacing the Pilot Orifice
NOTE: All natural gases use the same size pilot orifice
(0,635mm), as do all liquid propane (LP) gases (0,381mm).
Because of this, it is not normally necessary to replace the
pilot orifice unless converting the oven from natural to
propane, or from propane to natural, operation.
a. Refer to Figure 2-17. Unscrew the pi ot tube
compression nut and s ide it out of the way. Pu the
tube from the fitting to expose the pi ot orifice.
b. Remove the pi ot orifice.
c. S ip the new pi ot orifice into the pi ot tube.
d. Push the pi ot tube back into p ace unti it bottoms, and
ho d it in p ace. S ide the compression nut back into
p ace and engage the threads. Tighten the nut to a
snug fit with your fingers.
e. Gent y tighten the nut one comp ete turn with a wrench.
DO NOT OVERTIGHTEN THE COMPRESSION NUT.
3. Replacing the Bypass (Low Flame) Orifice
a. Refer to Figure 2-16. Note the ocations of the 1/2" hex
compression nuts that ho d the bypass ine in p ace.
Loosen the compression nuts using a 1/2" wrench.
b. Remove the bypass tube. Then, remove the bypass
orifice from the tube.
c. S ip the new orifice into the bypass tube.
d. Rep ace the tube onto its fittings on the so enoid va ve.
Whi e ho ding the tube in p ace, s ide the compression
nuts back into p ace and engage the threads. Tighten
the nut to a snug fit with your fingers.
e. Gent y tighten the nuts one comp ete turn with a wrench.
DO NOT OVERTIGHTEN THE COMPRESSION NUTS.
f. Rep ace the gas train and venturi by fo owing Steps a-
d in Rep acing the Main Orifice, above, in reverse order.
WARNING
After completing these procedures, perform a gas
leak test before operating the oven.
Figure 2-17 - Replacing the Main and Pilot Orifices
Main
orifice
Pilot
orifice
Pilot tube
Compression
nut
Main orifice
holder (attached
to gas train)
Venturi
assembly
Venturi
mounting
plate
Ignition
sensor
wire
SECTION 2 - INSTALLATION