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www.bromicheating.com
OpERATION DATA - FENWAL CONTROL BOX
The Series 35-60 is 24 VAC Microprocessor Based Direct
Spark Ignition Controls designed for use in all types of
heating applications. The control utilizes a microprocessor
to continually and safely monitor, analyze and control the
proper operation of the gas burner. The following operation
sequence is valid only where the components are installed
according to the manufacturers assembly and installation
instructions. Please do not modify the wiring configuration,
gas train or any other part of the heater assembly.
Application
The Fenwal electronic gas burner control system is suitable
for atmospheric gas burners for non-permanent operation.
The Fenwals configuration in the Tungsten Smart-Heat series
heaters limits it to volatile lockout, i.e. the restart from this
condition is possible by the interruption (for 5 seconds) and
subsequent restoration of the mains power supply.
Features:
•
24 VAC microprocessor based DSI control
•
Pressure switch monitoring
•
System diagnostic LED
•
Alarm output (normally closed contact)
•
Automatic reset 1 hour after lockout*
•
Custom prepurge and interpurge timings**
•
Multiple tries for ignition
•
Remote or local flame sensing
•
Flame sense test pins
Directions for use
Automatic controls are safety devices and shall not be
opened. The manufacturer’s responsibility and guarantee are
invalid if the control is unduly opened.
A regulation shutdown must occur every 24hours to
enable the unit to check its own efficiency (systems for non
permanent operation)
Connect and disconnect the unit only after switching off the
power supply
Avoid exposing the unit to dripping water
Ventilation and the lowest temperature ensures the longest
life of the control
Electrical Installation
•
The applicable state and local standards regarding
electrical safety must be respected.
•
Live and Neutral should be connected correctly; a
mistake could cause a dangerous situation.
•
Before starting the system check cables carefully for
incorrect installation
•
The ground terminal of the control, the metal frame of
the burner and the ground on the mains supply must be
well connected
Operation
When a call for heat is received from the thermostat
supplying 24 volts to TH/W, the control will reset, perform a
self check routine, flash the diagnostic LED, and a pre-purge
delay begins. Following the pre-purge period the gas valve
is energized and sparks commence for the trial for ignition
period.
When flame is detected during the trial for ignition, sparks are
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
main valve is de-energized immediately.
Should the main burner fail to light, or flame is not detected
during the trial for ignition period, the control will go into
lockout. The valve will be turned off immediately. Multi-try
Models will attempt two additional ignition trials before
going into lockout. The valve relay will be de-energized
immediately.
Recovery from lockout requires a manual reset by removing
24 volts from 24 VAC(R) for a period of 5 seconds. If there is
still a call for heat after one hour the control will automatically
reset and attempt to ignite the burner again.
If the established flame signal is lost the control will respond
within 0.8 seconds. The HV spark will be energized for a
trial ignition period in an attempt to relight the burner. If
the burner does not light the control will de-energize the
gas valve. Multi-try models will make two more attempts to
relight the burner. If the burner does not relight the control
will go into lock out as noted above. If flame is re-established,
normal operation resumes.
tecHnIcal data
Supply voltage
18 to 30 VAC 50-
60Hz
Operating temperature
-40°F +176°F
Ambient humidity
95%max at 104°F
Protection degree
IP00
Timings:
Self Check time
1.5 s
Safety time (TS)
10 s
Drop out time on running flame failure 0.8 s
Power consumption, at start up
300mA Max.
Power Consumption, Running
300mA Max.
Ignition
Ignition Voltage
15kV with 40pF load
Spark repetition rate
50/60 sparks/ sec.
Max. Cable length
1M
Recommended spark gap
3.5mm