Thermon HELLFIRE 400, Installation, Operation & Maintenance Instructions Manual

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H. HEATER SPECIFICATIONS
H.1 Performance
ࢦ
Clears ice and snow from switches with up to 28-foot
points or longer. (Recommended heating, 10,000 to
22,500 BTU/hr per foot of track coverage, based on
severity of local climate).
ࢦ
1500 scfm of heated air delivered via a duct system, point
nozzles and track duct vents.
ࢦ
Heat output range 200,000 to 400,000 BTU/hr LPG or NG,
field adjustable.
ࢦ
Output air temperature limited to 193 °C (380°F) maximum.
ࢦ
Burner efficiency, minimum 95%.
ࢦ
SCADA network connectivity via RS-485 communications
port.
H.2 Gas Firing
Table 1 – Gas Firing
Propane Natural Gas
Input rating, BTU/hr (kW)
200,000 - 400,000
(58 - 117)
Manifold pressure, inches
of water (kPa)
1.3 - 5.0
(0.32 - 1.23)
2.3 - 11.0
(0.56 - 2.69)
Supply pressure
in/w.c
1,2
(kPa)
7 - 14
(1.72 - 3.45)
12 - 14
(2.95 - 3.45)
1
With no more than 20% pressure drop, with all connected loads operating.
2
Inlet gas fitting, ¾” NPT female.
H.3 Gas Conversion
1. Heaters are factory set for use with propane gas.
2. To convert to natural gas change main gas pressure
regulator spring with the one supplied separately.
Adjust within specifications detailed in the table
above. Affix separate gas type plate supplied. Reverse
procedure to change back to original gas.
H.4 Electrical
Table 1 – Electrical
Voltage Phase Wiring
Running
Amps
1,2,3
Frequency
(Hz)
240 1 3 wire, L1, L2, N 7.5 60
208 3 4 wire, L1, L2, L3, N 7.3 60
460 3 3 wire, L1, L2, L3 3.6 60
575 3 3 wire, L1, L2, L3 3.0 60
1
On start up, peak in rush current is usually 6-8 times the running amp.
2
Current drops to running amperage after 4 seconds.
3
Two horsepower fan drive motor for all configurations.
H.5 Controls
Table 1 – Controls
Feature Description
Remote Start
Provide dry contract, rated for 24Vac
0.5 amp
Run and Alarm Indication
Contacts
Maximum 240Vac or 24Vdc, 10 amp
Magnetic Motor Starter Coil voltage 120Vac.
Motor Thermal Overload
Protection
Single phase, reset located on motor.
Three phase, thermal overload relay
fastened to contactor.
Thermostatically limited
output air temperature, cycling
380°F maximum, open on rise,
automatic reset.
Thermostatically limited
output air temperature, high
limit
420°F maximum, close on rise,
manual reset.
Direct Spark Ignition Control
Module
Fenwal 35 - 60
SCADA RS-485 MODBUS RTU
Rail Thermostat 9 °C (49°F) close on rise, automatic reset.
H.6 Wiring Terminations
Table 1 – Wiring Terminations
Function Size Range Termination Type
Power
#14 to #2 AWG
copper
Barrier Terminal Block, Tubular
with clamping screw.
Control #22 to #4 AWG AAR terminal posts, #14-24 UNS
RS-485
Communications #22 to #4 AWG
or
#26-#12 AWG
AAR terminal posts, #14-24
UNS or PCB plug in connector.
Tubular with clamping screw.
H.7 Safety Features
1. Minimum Air Pressure: Upon start up and request
for heat, the trial for ignition does not start until
adequate air pressure is developed. Burner is
extinguished immediately upon loss of air pressure.
2. High Temperature Limit: In the event the heated air
temperature exceeds 216
°C (420°F), the burner is
extinguished, the heater is shut down and locked out.
A manual reset is required.
3. Loss of Flame : If, upon start up and request for
heat, the trial for ignition fails to light the burner, or
the flame signal is lost while heating, the burner is
extinguished immediately.
4. Ductwork Electrical Isolation: As per, AAR standards
part 14.5.1D, “Recommended Design Criteria for
Assembly and Test of Insulated Track Fittings,
Dielectric Requirements”, ducting and nozzle
connections are electrically isolated to withstand a
maximum of 3000 Vac for 60 seconds to eliminate
possible interference with track circuits.