L.B. White 170 Premier - Manual (Page 18)

1. Open the burner end access doorand remove gas
hose from heater.
2. Remove the elbow and all screws at inlet of gas
control valve. See Fig. 21.
FIG. 21
3. Remove the burner retaining bolt at the underside of
the heaters base. For Premier 170 heaters, the bolt
is accesible through an opening in the heater’s
support leg. Use a ratchet with extension and 9/16
in. socket. See Fig. 22. For model TS080, also
remove the spacer between heater base and burner.
See Fig. 23.
FIG. 22
FIG. 23
This heater has two limit switches, one on the heat
chamber, the other on the fan housing. Both switches
should be tested annually, typically when the heater is given
a thorough cleaning.
1. Remove either high limit switch.
2. Holding the switch by one of its mounting legs, apply
a small flame only to the sensing portion on the back
of the switch. Be careful not to melt the plastic
housing of the switch when conducting this test.
3. Within a minute, you should hear a pop coming from
the switch, indicating the contacts of the switch have
opened.
4. Allow the switch cool down for about a minute.
Remove the red cap and firmly press the reset button
on the switch.
5. Check for electrical continuity across the switch
terminals to make sure the contacts have closed.
Install red cap.
FIG. 20
18
TESTING THE MANUAL RESET HIGH LIMIT SWITCHES
WARNING
Fire Hazard
■
Do not operate the heater with the high limit switch
bypassed.
■
Operating the heater bypassed high limit switch may
lead to overheating, possibly resulting in a fire, with
subsequent damage to the heater or property damage.
RESET BUTTON
SENSING
SURFACE
TERMINAL
FLAME
MOUNTING
LEG
BURNER ORIFICE AND GAS CONTROL VALVE
SPACER
BOLT