Lodge Manufacturing GMD1-80N ユーザーズマニュアル

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All installations and services must be performed by qualified service personnel.
 
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TABLE 2 
 
 
This gas furnace is equipped with a fixed orifice sized for the manifold pressure shown 
on the rating label.  The input can only be increased, or decreased, by adjusting the 
manifold pressure.  Remove the 1/8" threaded pipe plug located on the gas manifold.  
 
Use a U tube manometer or recently calibrated pressure gage to measure the pressure.  
To adjust the pressure, remove the screw cap from the regulator on  the gas valve and 
using the adjustment screw.  Decrease the pressure by turning the screw 
counterclockwise or increase it by turning the screw clockwise.   

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? CAUTION:  ADJUSTMENTS TO THE LISTED PRESSURE MUST NOT EXCEED 
0.3" WC A 0.3" WC adjustment will increase or decrease the input approximately 4.0%.   
 
Replace screw (cap) when adjustment is complete. 
The correct input can be assumed if the furnace manifold pressure is the same as that 
shown on the rating label if a gas meter is not available for natural gas or the unit is 
installed on an unmetered propane gas supply. 
Shut off the gas supply to the furnace.  Remove the pressure gage and re-install the 
pipe plug using a thread compound resistant to the action of LP gases. 
If the rated input cannot be obtained with the present orifice at the correct pressure, 
your local gas supplier may assist in sizing the proper orifice.  Thermo Products 
Engineering Department will gladly assist in sizing the orifice if you provide them with 
the heating value in BTU per cubic foot and the specific gravity of the fuel gas. 
 
 
M.  BURNER ADJUSTMENT 
 
The GMD1-80N furnace model utilizes an in-shot burner design that 
does not require an air shutter adjustment (air shutters are not used) for proper 
flame characteristics.  Burner box access cover must always be secured with all 
screws in place and tightened before operating furnace.
 
 
This unit is designed to not require any burner adjustment.  The flames should be 
checked by looking through the sight glass located on the burner box.  Burner flames 
should be clear, blue, and almost transparent in color.  (See Figure 9).  NOTE:  It is not 
unusual to have mostly blue flames with yellow or orange tips visible in the tube for 
propane gas.