50
51
FAULT FINDING CHARTS
Before using this flow chart please ensure that both the primary and under floor
heating systems are full and that all isolating valves are fully open. Please also
ensure that the room thermostats are calling for heat.
Hydraulic fault finding chart
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
Is the fused spur
switched on?
Is there 230V at
‘L’ terminal on PCB?
Is Green Power
LED illuminated?
Is 230V present on
all T2 terminals?
Is 230V present on
all T1 terminals?
Are the zone valve
and under floor heating pump
operating?
Is there 230V to NC Boiler
switch live connection?
(Check operation
of Volt free relay
connections if using 24V)
Is the boiler firing?
Check boiler connection
Turn the fused spur on
Replace 3A fuse in spur
Replace fuse on PCB
(2.5A 230 Vac Type 5x20)
Faulty PCB -
replace unit
Faulty room thermostat -
replace unit
Relay 1 faulty replace PCB
Relay 2 faulty replace PCB
System operating correctly
Electrical fault finding chart (master connecting box)
This testing procedure should only be carried out by fully qualified persons.
Testing should be done with all switches on and room thermostats calling.
Fault finding
complete
Adjust pump speed
and set flow rates
in accordance with
the system design
data as provided
NO
NO
Is the boiler firing
and the primary
pump operating?
Check for 230V signal
to boiler from master
wiring centre
YES
NO
Is there hot water
present prior to
under floor heating
mixing valve?
Check if the under
floor heating zone
valve is open
Electrical fault
(see electrical fault
finding guide)
Boiler fault
Primary flow and
return crossed or
debris in mixing valve
YES
Check 230V signal
to zone valve from
master wiring centre
NO
NO
Under floor
heating pump
operating
Check 230V signal to
pump from master
wiring centre
NO
Is the system
performing
correctly?
Ensure that manifold
lockshield valves are
fully open
YES
START
YES
YES
YES
YES
YES
YES
NO
NO
NO
Is hot water passing
through under floor
heating manifold?
Check temperature
adjustment on
under floor heating
mixing valve
YES
YES
NO
NO
Is there a visible flow
present through
all under floor
heating circuits?
Check if the
actuators are open
Electrical fault
(see electrical
fault finding
Pump fault
Zone valve fault
Electrical fault
(see electrical fault
finding guide)
Actuator fault
Check 230V
signal to actuator
from slave unit
YES
START
