Fulton Vertical Electric (FT-N) Thermal Fluid (hot oil) Heater - Manual (Page 56)

Fulton Thermal Corp.*Electric Thermal Fluid Heaters Manual* Version 2010-0423
Page 56
heater. The differential pressure switch will shut the unit down in the
event of loss of flow.
2. The differential pressure switch can be tested while only the pump is
running. Remove the metal cover on top of the switch and increase the
setpoint until the pump shuts down. Next, decrease the setpoint back to
its initial value and depress the pump start button to verify the pump will
re-start.
d) Pump Motor Starter
1. While firing, actuate the manual trip button on the pump motor starter.
Pump and burner will shut down. The blower should continue to run for
approximately thirty seconds. Attempt to restart pump by setting the
selector switch to “Pump” and depressing the pump start push button.
The pump should not start. Reset starter and start pump.
e) High and Low Fluid Pressure Switches
1. The only pressure required in the thermal fluid system is the pressure
required to maintain the proper flow. Pressure changes are monitored
with these switches, which will shut the unit down in case of a change in
the fluid flow.
2. With three position switch set to “Pump”, remove the cover from the
pressure switch and manually activate. Pump should shut down.
3. Repeat for each switch; replace covers. Note, if the burner was on, it
would also stop.
4. To set the low fluid pressure cutout switch, raise the setpoint with the
fluid at operating temperature and pump running, until the pump shuts
down. Note the setpoint and lower by 10 PSI, then re-start pump. The
setpoint at cutout should correspond to the reading on the output
pressure gauge.
5. With the unit cold and pump running, lower the high fluid pressure cutout
switch until the pump shuts down. Note the setpoint and raise by 10 PSI,
then re-start pump. The setpoint at cutout should correspond to the inlet
gauge reading.
f) Operating Temperature Controls
1. The safe maximum temperature of the fluid must be strictly adhered to.
2. When consulting fluid manufacturer’s literature for the safe maximum
fluid temperature, note that the temperatures quoted are the actual limit
to which any of the fluids may be subjected. It is important to remember
that in any fired heater there exists a “film” temperature which is higher
than the temperature of the bulk of the fluid.