Hamworthy 563216020, Installation, Commissioning And Servicing Instructions

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HAMWORTHY HEATING LTD
15
CHESIL-ELECTRONIC 500001181/K
8.0 FAULT FINDING
General fault finding is shown in Figure 17. If the Chesil unit still does not operate satisfactorily, consult
Hamworthy Heating for assistance.
Figure 17. Fault Finding Guide.
Fault Possible Causes Action
Pump will not run Unit up to pressure
No power to the unit
Isolator fuse blown
Cut In Pressure set incorrectly
Pump seized or faulty None
Check at source
Replace fuse in isolator. Note! Investigate cause of
blown fuse before restarting the unit
Adjust cut in pressure (see section 6.8)
Service or replace pump (see section 10)
Pump runs but will not build
up pressure Pump isolating valve closed
Pump not primed
Float switch faulty
Pump non return valve jammed
Blocked flow restrictor Open valve
Prime pump (see section 7.6)
Check water level and replace float switch.
Check valve
Check flow restrictor for blockage
Pump cuts in and out
rapidly (hunting) Value of cut in & coldfill pressure
set incorrectly
Non return valve not sealing
correctly
System Leak Adjust values
Clean valve seat or replace valve if necessary (see
section 10.4)
Trace leak and ensure system is sound
Pump runs continuously Value of coldfill pressure set
incorrectly
Pump relay faulty
System leak Adjust value
Replace faulty relay PCB in grey box (see section
10.5)
Trace leak and ensure system is sound
Pump cuts out at wrong
pressure Pressure gauge being compared
with is inaccurate.
Internal pressure sensor faulty.
Replace pressure gauge.
Replace pressure sensor (see section 10.6)
Maximum system working
pressure too high Coldfill pressure set incorrectly
Internal pressure sensor faulty. Adjust value
Replace pressure sensor (see section 10.6)
Boiler switches off un-
expectedly Hi or lo pressure alarms set
incorrectly
Safety circuit is wired incorrectly Adjust values
Check wiring with Wiring diagram in appendix
System pressure runs
consistently at cold fill
pressure
Small system leak Trace leak and ensure system is sound