Lennox International Inc. T-CLASS TM SEPARATED COMBUSTION UNIT HEATERS 사용자 설명서

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1- Periodically examine burner flames for proper 

appearance during the heating season. 

 2-  Before each heating season examine the burners 

for any deposits or blockage that may have 
occurred. 

 3-  Clean burners as follows: 

a-Turn off both electrical and gas supplies to unit. 
b-Disconnect gas supply piping, high tension and 
sensor leads. Remove gas manifold. Remove 
burner tray. 
c-Clean burners as necessary. Make sure that 
burner heads line up properly to ensure flame 
crossover.  Check spark gap on electrode and 
adjust if required. The gap should be between 
0.110 inch and 0.140 inch (2.79mm to 3.56mm). 
The gap may be checked with appropriately sized 
twist drills or feeler gauges. 
d-Reinstall burner tray, gas manifold, high tension 
and sensor leads. Reconnect gas supply piping. 
e-Restore electrical power and gas supply. Follow 
lighting instructions to light unit. Check burner 
flame. 

 

 

The flue passages and flue box should be inspected 
and cleaned prior to each heating season. The 
sequence of operation should be as follows: 

1-  Turn off both electrical and gas supply to unit. 
2-  Disconnect combustion air blower wiring. 
3-  Remove screws securing flue box to unit. Remove 

flue box. If necessary, remove blower assembly 
from flue box. Clean flue box with wire brush. 

4- 

Remove turbulator retention bracket and 

turbulators. Clean turbulators with wire brush. 

5-  Remove burners as described in section “Burners" 

section. 

6-  Clean tubes with a wire brush. 
7-  Reassemble unit. The combustion air and flue box 

gaskets should also be replaced during 
reassembly. 

8-  Restore electrical power and gas supply. Follow 

lighting instructions to light unit. Check operation of 
unit. 

 

 

 

Under normal operating conditions, the combustion air 
blower should be checked and cleaned prior to the 
heating season with the power supply disconnected. 
Use a small brush to clean blower wheel. 

 

 

 1-  Check all wiring for loose connections. 
 2-  Check for correct voltage at unit (unit operating). 
 3-  Check amperage draw. 

 

 

Check all vent and air inlet joints for tightness. Ensure 
that connections are sealed and that there are no 
blockages. 

 

 

If unit fails to operate check the following: 
 1-  Is thermostat calling for heat? 
 2-  Is main disconnect closed? 
 3-  Is there a breaker tripped or a fuse blown? 
 4-  Is gas turned on at meter? 
 5-  Is manual shutoff valve open? 
 6-  Is unit ignition system in lock out? If unit locks out 

again, call service technician to inspect unit. 

 7-  Is combustion air inducer proving switch closed? 

Obstructed flue will cause unit to shut off at 
combustion air inducer proving switch. Check flue 
passage and outlet. 

 

 

When ordering repair parts include the complete unit 
model number listed on the unit rating plate. For 
example: TUA045SNAF1.