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104414
DESA INTERNATIONAL
UNVENTED NATURAL GAS LOG HEATER
OPTIONAL
POSITIONING OF
THERMOSTAT
SENSING BULB
FOR MASONRY AND
FACTORY-BUILT METAL
FIREPLACE
If your log set cycles to pilot, but the room
temperature drops to a lower than ideal
comfort level before the log set comes back
on, you may want to reposition the thermo-
stat sensing bulb.
The thermostat sensing bulb is located on the
gas valve assembly. This location allows the
thermostat to keep the room temperature at
an ideal comfort level for most fireplace
applications. For positioning the thermostat
sensing bulb elsewhere, an adhesive-backed
mounting clip is available.
Tools needed: 5/16" hex driver or socket
1.
Locate the gas valve assembly and ther-
mostat sensing bulb (see Figure 30).
2.
With 5/16" hex driver or socket, loosen
the thermostat screw. Carefully slide
the thermostat sensing bulb out of the
retaining clamp (see Figure 32).
Note:
Do not remove the screw. Make
sure you tighten the screw after remov-
ing the thermostat sensing bulb.
IMPORTANT:
Do not force or bend
the thermostat sensing bulb or capillary.
Thermostat
Sensing Bulb
Gas Valve
Assembly
Figure 30 - Location of Gas Valve
Assembly and Thermostat Sensing Bulb
Figure 31 - Adhesive-backed Mounting
Clip
Adhesive-
backed
Mounting Clip
Figure 33 - Locating Thermostat Sensing
Bulb on Masonry Fireplace
Thermostat
Sensing
Bulb
Adhesive-
backed
Mounting
Clip
Thermostat
Sensing
Bulb
Figure 34 - Locating Thermostat Sensing
Bulb on Factory-built Metal Fireplace
Capillary
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Adhesive-
backed
Mounting
Clip
Glass Doors
Figure 35 - Installing Thermostat Sensing
Bulb behind Glass Doors
Thermostat
Sensing
Bulb
Capillary
Thermostat
Sensing Bulb
Do Not Crimp
Capillary
Adhesive-
backed
Mounting
Clip
Figure 36 - Positioning the Thermostat
Sensing Bulb in the Vertical Position with
the Capillary at the Bottom
3.
The thermostat sensing bulb may be
located to the lower right front side of
fireplace. Determine location of sens-
ing bulb, but do not mount sensing bulb
until step 5. If you have a masonry fire-
place, see Figure 33 for location.
If you have a factory-built metal fire-
place, see Figure 34 for location.
If your fireplace has glass doors, posi-
tion sensing bulb directly behind door
gap on right bottom side (see Figure 35).
Figure 32 - Removing Thermostat Sensing
Bulb
Screw
Retaining
Clamp
Thermostat
Sensing Bulb
4.
The mounting clip must be a minimum
of 3" from bottom of fireplace to pre-
vent crimping of capillary. Once you
have decided on a location, clean the
area thoroughly. Remove the paper
backing from the adhesive on back of
mounting clip. Press the clip into the
new location so that the thermostat
sensing bulb will be positioned verti-
cally with the capillary at the bottom
(see Figure 36). Slide the thermostat
sensing bulb into the clip.
IMPORTANT:
Do not crimp capillary.