Graco FOAM-CAT 200 Series, Instructions And Parts List

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Troubleshooting
Electrical Resistance Checks
WARNING
To reduce the risk of serious injury, including fluid
injection or electric shock:
1. Follow the Pressure Relief Proce-
dure on page 6 before checking or
adjusting any part of the system or
any component and whenever you
are instructed to relieve pressure.
2. Disconnect the main electrical power
to the heater before removing any
heater panels.
Measuring the resistance of a part helps determine if it
is working properly. If you get a measurement other
than those given in the following procedures, replace
the faulty part.
Setup
1. Relieve the pressure, and shut off the main power
to the heater.
2. Remove the appropriate control panels.
3. Determine the approximate temperature of the
part; if the heater was operated recently, the
temperature will be high.
4. To remove wires, use the accessory tool, P/N
110968 or a 3/16 in. wide screwdriver. Insert the
tool into the slot below each wire on the terminal
block, push the tool away from the wire and pull
out the wire. See Fig. 9.
5. To reconnect the wires, push the tool into the slot,
slide in the wire and release the tool.
Fig. 9
01698
Tool 110968
Heater Sensor Probe
1. Follow the previous Setup instructions.
2. Remove the heater control panel (216). See Fig.
13, page 25.
3. Unplug the connector P1 at position J2 on the
heater circuit board in question. See Fig. 10.
4. Check the resistance across the two outside
terminals of connector P2. The resistance should
be:
45K to 55K ohms at 77
_
F (26
_
C), or
10K to 20K ohms at 120
_
F (49
_
C)
5. To replace the sensor probe (256), see page 22.
Thermostat
(normally closed)
1. Follow the previous Setup instructions.
2. To check continuity from inside the wiring junction
box, remove the wires from connector T1 and
check continuity across the wires. See Fig. 10.
3. To check continuity at the thermostat, remove the
front heater element shroud (238). Check for
continuity across the terminals at each switch, with
one lead disconnected and after pushing the reset
button. See Fig. 13, page 25.
4. If there is no continuity, replace the thermostat.
See page 26.