FULTON FT-0080C, Installation, Operation, Maintenance And Parts Manual

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FT-C Vertical Electric Thermal Fluid Heater Manual 12 2013 ISSUE 1
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n) Improper switch setting
1. The High Outlet Pressure Switch should be set at 0.35 barg over the maximum pressure
read on the heater outlet pressure gauge during proper operation at the coldest ambient
temperature expected.
p) Faulty Switch
1. If the pressure is verified and reads correctly below the set point on the switch and the
sensing line to the pressure switch is open, the pressure switch is faulty. Replace the
switch, set for the desired set point and test for proper operation.
q) High inlet pressure switch
1. The High Inlet Pressure Switch is a normally closed switch that opens with improper
heater inlet pressure.
2. The purpose of the High Inlet Pressure Switch is to protect the heater from building too
high of a pressure.
3. Typical electric heaters have a maximum working pressure of 10.34 barg with 6.9 barg
safety valve(s) on the heater outlet manifold. The High Outlet Pressure Switch should be
set at 0.35 barg over the heater outlet pressure as read at ambient temperature assuming
that none of the conditions mentioned below are true.
4.5.2
TROUBLESHOOTING : TRIPPED HIGH OUTLET PRESSURE SWITCH
a) An obstruction downstream of the heater
1. Any obstruction downstream of the heater will increase the pressure that the heater outlet
sees. This obstruction will generally result from an improper valve setting.
2. Observe the heater outlet pressure at temperature with all users / heat exchangers calling
for heat (100% user). Observe the heater outlet pressure at temperature with all users /
heat exchangers not calling for heat (100% bypass).
3. Bypass regulating valve(s) should be adjusted to equal flow condition through users. Call
or e-mail Fulton for further details.
4. It may be possible that an automatic control valve has failed. If this is the case, the valve
should be replaced.
b) Improper switch setting
1. The High Inlet Pressure Switch should be set at ambient temperature. The setting should
be 0.35 barg higher than the maximum pressure read on the heater outlet pressure
gauge during proper operation.
c) Differential Pressure Switch
1. The Differential Pressure Switch is a normally open diaphragm switch that closes with a
proper heater differential pressure between the heater inlet and outlet.
2. The purpose of the Differential Pressure Switch is to protect the heater from too high of a
temperature and to protect the thermal fluid from exceeding its maximum film
temperature. Each heater model number has a specific minimum differential pressure.
3. See Section 1 if you do not know this pressure. This pressure is the difference in
pressure between the heater inlet pressure gauge and the heater outlet pressure gauge.