HRS AquaModule AMB15, Operating Instructions Manual

Page: 39 / 48

t.
01923 232335
www.hrshevac.co.uk 39 of 48
HRS Hevac Ltd AquaModule AMB
Installation, Operating & Instruction Manual
13 Trouble shooting
FINDINGS PROBABLE CAUSES REMEDIES
Pump not operating Locked rotor or damaged Force to rotate. Replace if required
Corresponding led is not lit Replace Power Board
Pump relay damaged Replace Power Board
Pump protection fuse blown Check then replace if necessary
High Alarm condition detected Clear alarm then reset system
No voltage to control board
terminals Check power supply cable and fuses
No voltage to pump motor terminals Check protection fuse on main
board, cable condition and
connections
Controller improperly set Contact After Sales Service
Low temp alarm condition Primary pump stopped See “Pump not operating”
Too low primary temperature Check for a closed valve in the
primary
Too high tap water flow rate (SI) Reduce buffer vessel charging flow
rate
Set point too high
3 way valve remains closed See “Modulating valve does not
operate”
Modulating valve does not
operate Damaged or broken actuator Test and replace if necessary
Broken or improperly tightened
coupling Check and replace if necessary
Valve blocked Replace
No signal from the controller Check then replace if necessary
Supply wires improperly tightened Check wires, re-tighten connections
Actuator stroke restricted Dismount then clean the valve
High alarm condition detected Charging pump stopped (SI
versions) Refer to ‘’Pump not operating’’
above
Low recirculation flow rate (I
versions) Check and fix problem
Alarm differential too low Check and set the controller
Modulating valve not closing Refer to previous box above
Too much differential of pressure
across the modulating valve Check the way the TWM is piped-
up. Mixing arrangement should be
used
Correct temperatures across
the exchanger not obtained.
Valve and pumps operating
satisfactorily Excessive exchanger scaling at the
primary or secondary side Open and clean the exchanger
according to cleaning instructions
Primary pipe work obstructed or
strainer upstream clogged Inspect primary pipe work.
Clean strainer on the primary side
Isolation valve closed Open isolation valves
Air presence in the primary Purge. Check no high parts where
air could be trapped exist
Excessive pressure drops Check pipe size is suitable for
nominal flow rate
Temperature does not
increase in the buffer vessel
and the tap water value is
correct. Recirculation flow rate exceeds
charging flow rate. Check and measure charging and
recirculation flow rates. Adjust when
necessary
Recirculation FR < 0.6 x Charging
FR