L.B. White Therma Grow HW120 Manuel Du Propriétaire page 23

to gas control valve
-- Gas control valve opens
-- Ignition occurs.
-- Flame sense current is passed through burner flame
back to ignition control.
-- Igniter stays powered until ignition control proves
flame sense
-- Igniter then shuts down.
-- Gas control valve stays open
-- Room warms to desired temperature.
-- Thermostat is satisfied.
-- Heater shuts down.
-- Process starts again on a call for heat.
IGNITION TRIAL SEQUENCE:
-- First trial for ignition takes approximately 30 seconds
-- Two more ignition trials occur
-- Second trial immediatley follows if first trial failed.
-- If second trial fails
-- Ignition control starts a 15 minute waiting period
-- Allows the ignition interruption to pass
-- At end of 15 minutes
-- Ignition control attempts third and final ignition trial
-- If igntion control does not prove burner flame after
third trial, the control goes into safety lockout (3 flash)
-- Gas valve closes.
-- Hot surface igniter shuts down
-- Fan motor stops.
-- To retry for ignition, turn the heater off and then on.
Therma Grow™ Greenhouse Heaters
Owner's Manual • Therma Grow™
23