Fenwal 35-60 Dsi; Electrical Requirements - Schwank sportSchwank Series Installation And Owner's Manual

8. ELECTRICAL REQUIREMENTS

The heater, when installed, must be electrically grounded in accordance with local
codes, or in the absence of local codes, with the National Electrical Code ANSI/NFPA
70, or the Canadian Electrical Code, CSA C22.1.
Single heater requires a 24 Volt, 60 Hz electrical transformer sized at 40 VA. When
multiple heaters are controlled in a single zone, a 24 Volt 60 Hz transformer sized at 40
VA for the first heater, plus 20 VA for each additional heater in the zone. If the total VA
requirement exceeds a standard available transformer rating (in between sizes) select
the next higher available transformer VA rating.
For example, five heaters controlled together (wired in parallel), require a 150 VA
transformer (40 + 20 + 20 + 20 +20 = 120 -> go to available size = 150 VA).
PROPER WIRING POLARITY MUST BE MAINTAINED, particularly when grouping the
heaters in a zone.
Ensure that wire gauge is properly sized to suit distances between control and heaters.
Malfunction of the heating system will result if the voltage varies by more than +10% or
-10%.
9. SEQUENCE OF OPERATION FOR FENWAL 35-60 DSI CONTROL
WARNING: The Series 35-60 uses voltages
of shock hazard potential. Wiring and initial
operation must be done by a qualified ser-
vice technician.
Start up - Heat Mode
On a call for heat the Fenwal 35-60 control will reset, per-
form a self check routine, flash the diagnostic LED for up to
four seconds. The gas valve and spark are energized com-
mencing the 21 second trial for ignition period.
When flame is detected during the trial for ignition, spark is
shutoff immediately and the gas valve remains energized. The thermostat and main
burner flame are constantly monitored to assure the system continues to operate
properly. When the thermostat is satisfied and the demand for heat ends, the gas valve
is de-energized.
Flame Failure - Multi Trial Model:
Should the main burner fail to light, or the flame is not detected during the first trial for
ignition period, the gas valve is de-energized and the control goes through an inter-
purge delay before another ignition attempt. The control will attempt two additional igni-
tion trials before going into lockout and the valve relay is de-energized.
Recovery from lockout requires a manual reset by either resetting the thermostat or
removing 24 volts for a period of 5 seconds. If the thermostat is still calling for heat af-
ter one hour the control will automatically reset and attempt to ignite the burner again.
Flame Failure - Re-Ignition:
Page 10
sportSchwank Manual
IM080731
RD: APR 2019
RL: 01B