HVFL Unvented Gas Logs
18
59D1016
ELECTRICAL WIRING - MILLIVOLT
OPERATION OF THERMOSTAT SENSOR
1. Follow millivolt lighting instructions on lighting plate
attached to unit or in homeowner’s manual.
. With control knob in the “ON” position make sure
the ON/OFF switch is in the “OFF” position.
Figure
24
3. The unit is now being controlled by the thermostat
sensor. The sensor will now cycle the burners on
and off. You can adjust how often the unit cycles
by turning the control knob on the sensor.
HIGH
LOW
26D3317
THERMOST
AT
SETTING
FP2809
controls
Control Knob
On/Off Switch
T-Stat Sensor
FP809
Figure 24 -
Control Knob in “ON” Position and
ON/OFF Switch in “OFF” Position
CHECkING SYSTEM OPERATION
The millivolt system and individual components may be checked with a millivolt meter hav-
ing a 1-1000 mV range. Conduct each check shown in chart by connecting meter test leads
to terminals as indicated.
A. Complete Millivolt System Check
(“A” Reading - Thermostat contacts CLOSED - Control knob “ON” - Main burner should
turn ON)
1. If reading is more than 175 millivolts and the automatic valve still does not come on,
replace the control.
. If the closed circuit reading (“A” reading) is less than 175 millivolts, determine cause
for low reading, proceed to Section B.
B. Thermopile Output Reading Check
(“B” Reading - thermostat contacts OPEN - Main burner OFF
1. Check gas pressure to the unit. If gas pressure is within minimum and maximum on
data plate, then check pilot voltage, 500 millivolts minimum. If the minimum millivolt
reading is not obtainable, replace pilot.
Connect
Switch or
Meter
Check
Meter Leads
Thermostat
Reading
Test
To Test
To Terminals
Contacts
Should Be
A
Complete
& 3
Closed
Minimum 175
System
B
Thermopile
1 &
Open
Minimum 500
Output
