AERCO KC1000 Heater 2002 - Manual (Page 58)

MAINTENANCE
6-16
6.11 LOW WATER CUTOFF PROBE INSPECTION AND CLEANING
KC Heaters feature a Low Water Cutoff sensor probe (P/N 122843 as part of probe/capacitor assembly
P/N 69126) which should be inspected and, if needed, cleaned every six months or replaced (if damaged)
to ensure proper operation. See Figure 6.20.
To inspect and clean, proceed as follows:
1. Disconnect power to the boiler and drain the water from the boiler system.
CAUTION!
Do not drain the unit without venting the shell! A vacuum in the unit may displace the liner causing
serious damage not covered by warranty.
2. The LWCO probe is installed near the top of the heat exchanger. Unscrew the brass coupling in
which the probe is installed and remove the probe/coupling assembly from the recess. Take care
to not damage the wire connected to the probe. See Figure 6.20 for a picture of the probe
installed and uninstalled (shown with brass coupling attached and wire/hardware removed).
3. Inspect the metal end of the probe for scale and/or corrosion.
4. If the probe needs cleaning, use sandpaper of 100 grit or more to remove any scale or corrosion.
5. If the probe is heavily pitted or is damaged in any way, replace with a new probe.
6. Reinstall the probe, refill boiler system with water, reapply electrical power, and test to ensure
probe is working.
Figure 6.20 – Low Water Cutoff Probe and Brass Coupling
LWCO Sensor
Probe
LWCO
Probe/Capacitor
assembly
(P/N 69126)