TROUBLESHOOTING
Table 3 lists the problems and solutions in
troubleshooting in RP920 Controller,
Table 3. RP920 Problem-Solution Chart.
Problem
Solution
1. When setpoint is changed in both directions, BLP
Replace setpoint module and recalibrate,
does not reach the minimum of 0.5 psi (3.5 kPa) or
maximum of 2 psi (14 kPa) below mainline pressure.
2. BLP does not react properly or reacts too slowly.
3.
Continuous bleed-off at Port 4.
I
4. Air leak at BLP test tap.
Plug with 14002172-001 Gage Tap Repair Plug or
renlace connector block module.
When authority setting is changed in both directions,
BLP does not change.
RP920B and D only:
Replace switch block module (with startpoint prv).
Compensation startpoint cannot be changed by
Recalibrate if needed.
adjustment of compensation startpoint knob.
10. No air is supplied to primary sensor (Port 3) with
Replace connector block module.
restriction switch in the unblocked position.
11.
Air
leaks at Port
3
with restriction switch in blocked
Tighten restrictor switch screw or replace connector
position.
block module.
12. Air leaks at restrictor switch.
13. Controller produces unacceptable noise (high
frequency humming).
Identify which prv is generating the noise by touching
the related adjustment knob or screw until noise changes.
If source is setpoint or operating point prv, replace
setpoint module. If source is in compensation startpoint
prv, renlace switch block. If needed, recalibrate,
REPAIR
The following repair procedures cover recommended
repair for the RP920 as listed in the PARTS AND ACCES-
SORIES section under PARTS LIST.
NOTE? Before doing any repair on the RP920, shut off
system air and disconnect all tubing from
ports.
2.
3.
Install the new gasket and secure the replacement
module to the base with the screws.
Connect and turn on the system air. Perform the
operational check.
SETPOINT KNOB REPLACEMENT
MODULE REPLACEMENT
1. Remove the module to be replaced, including the
gasket, by loosening the screws
Simply lift off the setpoint knob and replace it with the
new one (Fig.
85-0142
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