Fulton Hopkins (HPN) Horizontal Coil Thermal Fluid (hot oil) Heater - Manual (Page 56)

© Fulton Companies 2014
OPERATION
HPN-IOM-2014-0416
SECTION 3
3-24
!
WARNING
To ensure that your Fulton equipment
is kept operating safely and
effi
ciently, follow the maintenance
procedures set forth in this manual.
The end user of the heater must
maintain all labels on the heater
in clean, legible condition. All
connections and safety devices, both
mechanical and electrical, must be
kept clean, with ease of access for
inspection, use and maintenance.
 Modulating Controls
All coil models are standard-equipped with modulating controls.
1. The modulating temperature controller continuously regulates the outlet
fl uid temperature between the minimum fi ring rate and high fi re. When
the unit is on low fi re and the temperature continues to climb past the
setpoint, the heater will shut down. It will typically re-start when the
process temperature drops 7°F below setpoint.
2. Minimum load depends on the degree of modulation provided. Typically
3:1 or 5:1 modulation is provided. In this case minimum load is one third of
full fi ring rate.
3. The modulating temperature controller is set to maintain the desired fl uid
outlet temperature. Due to the temperature rise across the heater, this may
be considerably higher than the inlet temperature.
4. If the unit is equipped with a modulating controller, it will be located on
the face of the electrical cabinet. The temperature setpoint in the controller
can be adjusted following the instructions in the component data sheet
section of this manual.
 Pressure Gauges
All units have two pressure gauges measuring the thermal fl uid pressure at the
inlet of the heater and at the outlet of the heater. A third gauge measures the
pump suction pressure.
1. The diff erence between the readings of the two gauges indicates the
pressure loss across the heater. The diff erence must not fall below the
recommended value. Recommendations are based on heater size and
are listed in manual and on the product data submittals on www.Fulton-
heater.com.
2. The gauge indicating the pressure of the fl uid at the inlet is labeled “Inlet“.
The “Outlet” gauge indicates the pressure at the outlet, and in eff ect
indicates the resistance of the external pipework circuit. The pressure
gauge indicating pressure at the inlet of the pump is labeled “Suction.”
 Test of Ignition Safety System Shutoff
Test the ignition system safety shutoff as follows:
1. Shut the pilot valve.
2. Close the last gas valve between the inlet to the burner and the butterfl y
valve.
3. With the main gas cock (inlet manual gas valve) open, the burner should
be cycled on. After all the safety limits such as gas pressure, water fl ow and
temperature are satisfi ed, the blower will run and pre-purge the heater.
4. Once the purge is complete (30 seconds), the ignition transformer will be
energized. There will be a 4 second trial for ignition period. During this