Fulton Vertical Tubeless (FT-A) Thermal Fluid (hot oil) Heater - Manual (Page 67)

Questions? Call (315) 298-5121, or visit us online at www.fulton.com
SECTION 4
FTA-IOM-2013-0227
MAINTENANCE
4-7
!
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.
4
CAUTION
All maintenance procedures should
be completed by trained personnel.
Appropriate training and instructions
are available from the Fulton Service
Department at (315) 298-5121 or your
local Fulton Thermal Representative.
Air Switch
Remove the ¼” copper tubing from the bottom of the air switch with the fan
running. Air switch should trip the interlock circuit. Re-attach copper tubing and
reset fl ame programmer.
Air Filter Box Switch (if equipped)
With heater running at high fi re, block opening to air fi lter box by 50%. Slowly
close off further until switch trips. Air fi lter switch should trip at just over 50%
blockage. Monitor combustion valves during this procedure.
Temperature Limit(s)
Adjust set point(s) of temperature limit(s) down to a point lower than the process
variable (PV). PV is typically the current fl uid temperature at the heater outlet.
Solid-state controls will deactivate a control relay powering a set of n.o. contacts
in the interlock circuit. Analog controls will open their contacts in the interlock
circuit. Trip temperature should be within 5 degrees of PV temperature. Reset
temperature limit if reset exists and reset fl ame programmer.
High/Low Gas Pressure Switch
Shut off the main gas valve prior to the gas train and attempt to light the unit.
After the gas valves open during the ignition trial, the low gas pressure switch will
trip. Reset the low gas pressure switch and fl ame programmer. Open main gas
valve prior to gas train and close gas valve between last actuated gas valve and
burner. Attempt to light the unit. After the gas valves open, the high gas pressure
switch will trip. Reset the high gas pressure switch and the fl ame programmer,
then open downstream valve.
Troubleshooting
FLOW CIRCUIT/ CIRCULATING PUMPS
The fl ow circuit is the electrical circuit that enables the circulating pump(s). Your
thermal fl uid pump(s) will remain on until the fl ow circuit opens to disable the
pump starter or the Off / Pump / Heat switch is turned to the “Off ” position. Items
in the fl ow circuit may include paddle type fl ow switches, a high inlet pressure
switch, a low inlet pressure switch, a high outlet pressure switch and a diff erential
pressure switch.
LOW INLET PRESSURE SWITCH
All A-model heaters have a Low Inlet Pressure Switch. This is a normally open
switch that closes with proper heater inlet pressure. This switch is generally a
mercury bulb type switch. Mercury will rest towards the green cap of the mercury
bulb in a “made” condition.
The purpose of the Low Inlet Pressure Switch is primarily to protect the heater
from a low fl ow condition. The Low Inlet Pressure Switch should be set at 5 psi
below normal heater inlet pressure as read at operating temperature assuming
that none of the conditions indicated in Table 10-A are true. Refer to Table 10-A