![background image](http://html1.mh-extra.com/html/l-b-white/premier-cs700/premier-cs700_owners-manual-and-instructions_3216512022.webp)
Premier Ductable Heater
www.lbwhite.com
Owner’s Manual • Premier Ductable Heater
22
Manual Reset High Limit
Switches
WARNING
Burn Hazard
■ Do not operate the heater with the high limit
switch bypassed.
■ Operating the heater with the hight limit switches
bypassed may lead to overheating, possibly
resulting in a fire, with subsequent damage to
the heater or property damage.
Each heater has two high limit switches. One is located at
the burner end of the heater on the heat chamber. Their
purpose is to de-energize the gas control valve if the
heater should overheat. See Fig. 25. The other is located
on the motor end above the fan motor. See Fig. 26.
FIG. 25
FIG. 26
HIGH LIMIT
SWITCH
HIGH LIMIT
SWITCH
Burner end high limit:
Protects the burner and associated wiring from
overheating caused by excessive gas pressure.
Motor end high limit:
Protects from overheating if the duct is kinked, restricted,
or if the air inlet is blocked.
The switches are wired in series and will
disconnect power to the gas control valve if either
senses an overheat condition.
Both high limit switches should be tested a
minimum of once per year when the heater is
given a thorough cleaning.
1. Remove the high limit switches from the heater. Also
remove the red cap from both switches.
2. Holding a switch by one of its mounting legs, apply a
small flame only to the sensing portion on the back
of the switch. See Fig. 27. Be careful not to melt the
plastic housing of the switch when conducting this test.
FIG. 27
3. Within a minute, you should hear a “click” indicating the
contact of the switch opened.
4. Allow the switch to cool for about a minute before firmly
pressing its reset button. Put the red cap back on the
switch.
5. Check for electrical continuity across the switch
terminals to make sure the contacts have closed.
RESET BUTTON
TERMINAL
SENSING
SURFACE
MOUNTING
LEGS