Fulton Vertical Tubeless (FT-A) Thermal Fluid (hot oil) Heater - Manual (Page 50)

© The Fulton Companies 2013
OPERATION
FTA-IOM-2013-0227
SECTION 3
3-10
!
WARNING
All information in this manual is for
reference and guidance purposes,
and does not substitute for required
professional training, conduct,
and strict adherence to applicable
jurisdictional/professional codes and
regulations.
Should overheating occur or the gas
supply fails to shut off , manually shut
off the gas supply external to the
equipment .
temperature controller calling for heat, the fl ame programmer starts the
cycle and the blower motor starts prepurge.
2. The air proving switch must be closed now. Air dampers remain in
maximum position.
3. (Gas Pilot) Provided all safety interlocks are proven, ignition and pilot are
energized and a timed trial for pilot ignition begins. After the pilot fl ame is
proven, the main fuel valve is energized. Ignition is turned off when fl ame
is registered and the main gas valves open.
4. (Spark Ignition) At the end of purge time, provided all safety interlocks
are proven, the spark is on and oil valves are opened. When the fl ame is
proven, the spark is shut off .
5. When the fl uid temperature reaches the off setting (typically the setpoint
plus 2 to 5 degrees) of the operating temperature controller, all fuel valves
are closed.
The burner motor stops and the entire system is ready for restart on demand.
MODULATING BURNER
The function of the fl ame programmer must be greatly extended in a modulated
system. Along with limit controls, operating controls and interlock devices, the
programmer automatically controls the operation of the burner, blower motor,
ignition, main fuel valves and modulating motor.
The sequence of operation is as follows:
1. Beginning with power on, limit switch closed, fuel valves closed, and
modulating limit controller closed and calling for heat, the fl ame
programmer begins its cycle and the blower motor starts prepurge.
The modulating circuit closes, driving the air dampers to maximum for
prepurge.
2. The air fl ow proving switch must be closed now. After timed prepurge, the
modulating motor drives the air damper to its low fi re position. All start
interlocks must be proven or the fl ame programmer will lockout.
3. Ignition and pilot are energized and a timed trial for pilot ignition begins.
After the pilot fl ame is proven, ignition turns off and the main fuel valve is
energized. Pilot fuel is turned off and the modulating motor is released to
automatic.
4. When the modulating motor is released to automatic, it receives its signal
from the modulating temperature controller. The modulating motor then
drives the modulating fuel valve and air damper in proportion to the heat
demand.
5. During the initial call for heat, the modulating fuel valve and air damper will
drive to their full-fi re position. As the temperature set point is approached,
the modulating motor will continue to reduce the input until low-fi re
position is reached. Input automatically increases and decreases according
to load demand.