AERCO Electronic Control Valve - Manual (Page 23)

VA-115 INSTRUCTIONS – ELECTRONIC CONTROL VALVE, CXT-E
7-3
TABLE 7-1. TROUBLESHOOTING – CONTROL VALVE CXT-E (Continued)
NO. FAULT INDICATION PROBABLE CAUSE CORRECTIVE ACTION
T3 (Continued) 3. Steam pressure, or
heating fluid
temperature too low.
4. For Steam Heating
System, Trap or
Orifice in Heater
Condensate Line is
malfunctioning.
3. Check the high side steam pressure to
the Control Valve to ensure it is correct.
For high temperature (HT) water,
ensure there is good circulation.
a. If steam pressure or HT water
temperature is lower than the system
design spec., correct as necessary.
b. If high side steam pressure drops, or
there is no HT water circulation as
the Control Valve opens, there may
be a partially closed valve in the
upstream line. Also, the strainer may
be clogged. Correct as needed.
4. Check for improper operation of Trap or
clogged Orifice in Condensate Line as
follows:
a. If low side pressure gauge shows
pressure but steam does not heat
properly, CAREFULLY break
Condensate Line connection AHEAD
of Trap or Orifice.
b. Allow condensate to run out into floor
drain.
c. If Heater outlet temperature rises to
desired setpoint with condensate
connection open, repair or replace
Trap or unplug Orifice.
T4 Wide variations in
Heater outlet temper-
ature during wide
variations in flow . 1. System not properly
sized to maintain
desired setpoint.
1. Review system flow characteristics to
ensure Heat Exchanger and Valve are
properly sized to maintain the desired
outlet temperature.
T5 Rapid fluctuations in
heater outlet temper-
ature which do not follow
load changes 1. Temp. Controller
sensitivity not set
correctly
2. Steam System Trap
or Orifice fault
1. Adjust Temp. Controller sensitivity
2. Refer to T3, Corrective Action 4 above
and proceed as indicated.