Williams 1773511, 1773512 First Firing the Furnace, Checking the Gas Inlet Pressure, A B C

Models: 1773512 1773511

1 24
Download 24 pages 4.62 Kb
Page 11
Image 11
First Firing the Furnace

First Firing the Furnace

Start the furnace following the instructions given in the “Operating Instructions”. The first lighting may be difficult because of the air trapped in the gas lines. During initial firing of the furnace, residual manufacturing grease will bake out and smoke will occur which is not a health danger. To prevent nuisance and operation of fire alarms, ventilate the room for the first two hours of operation.

Checking the Gas Inlet Pressure

The gas inlet pressure can be measured by connecting a test gauge to the connection provided on the gas valve. (Figure 8 - A) Once installation is complete, the gas inlet pressure must be checked. The minimum gas inlet pressure must be as shown in “Technical Data”. After checking the gas inlet pressure, disconnect the test gauge and firmly tighten the screw of the gauge connection, then check for gas leaks. Correct any gas leaks before operating the furnace.

Checking the Gas Manifold Pressure

The gas manifold pressure can be measured by connecting a test gauge to the connection provided on the gas valve. (Figure 8 - B). The furnace comes set from the factory at the correct manifold gas pressure. After the installation is completed, the gas manifold pressure must be checked both in Hi and Lo input. Turn the control knob to switch the unit from Hi to Lo input. The position of the knob in which this occurs depends on the actual room temperature. The gas manifold pressure must be as shown in “Technical Data”. Differences of plus or minus 0.1 in. w.c. are acceptable. If the Hi or Lo gas manifold pressures are different from the values given in the “Technical Data” or are more than 0.1 in. w.c., shut off the furnace and contact a qualified service technician for correction.

For instructions about adjustment of the manifold Hi and Lo pressures, see the "Servicing” section. After checking the gas manifold pressure, disconnect the test gauge and firmly tighten the screw of the gauge connection, then check for gas leaks from it. Correct any gas leaks before operating the furnace.

Figure 8

A B C

A. Test gauge connection for gas inlet pressure

B. Test gauge connection for gas manifold pressure

C. Nut for Hi pressure adjustment (pressure regulator)

D. Screw for Lo pressure adjustment (Hi-Lo

Doperator)

E

F

E. Electric clamp connection F. Gas supply inlet

10

Page 11
Image 11
Williams 1773511 First Firing the Furnace, Checking the Gas Inlet Pressure, Checking the Gas Manifold Pressure, A B C