Meco Pellematic PES 12-20, Installation Manual

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Malfunctions
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13
Malfunctions
13.1 Malfunctions - what to do
Follow the sequence described for handling malfunctions.
• The heating system switches off automatically if a malfunction occurs.
• The control unit display shows a malfunction alarm text.
• You have to rectify the cause of the malfunction.
• After rectifying the malfunction, you have to reset the fault text by pressing Enter before starting the heating system
again.
13.2 Malfunction texts
The malfunction text displayed on the screen provides information on the type, time and status of the malfunction as
well as help for troubleshooting.
Malfunction texts have 3 statuses
1. C – New malfunction: when the malfunction comes.
2. G – Rectified malfunction: when the malfunction goes.
3. Q – Reset malfunction: when the malfunction quits.
Being able to trace the sequence of malfunctions will help you to establish the cause of the malfunction.
13.3 Overview of malfunction alarm texts
This is a list of all malfunction alarms that are displayed
Table 13.1 Boiler sensor
Display:
Boiler S fr
Description: Boiler sensor fracture, measuring circuit from boiler sensor is open
Cause and Remedy: sensor not connected ► connect sensor at input
sensor defect
► measure sensor (approx. 2kΩ at 77°F) replace if
required
sensor cable defect
► replace sensor
signal input defect
► change CMP PLC
sensor temp. too high ► sensor temperature above measuring range (230°F)
Display: Boiler S sh-c
Description: Boiler sensor short circuit, measuring circuit from boiler sensor is shorted out
Cause and Remedy: sensor defect ► measure sensor (approx. 2kΩ at 77°F) replace if
required
sensor cable defect
► replace sensor
signal input defect
► change CMP PLC
sensor temperature too low ► sensor temperature below measuring range (14°F)
Installation Manual PES 36–56 PE 3671 USA 2.3