Control And Adjustment At Full Load; Control And Adjustment At Low Load; Decommissioning - andrews CWH30/200 Installation, Operation And Maintenance Manual

CONTROL AND ADJUSTMENT AT FULL LOAD

1. Switch the water heater off and fl ush system until the
tank is completely cooled down
2. Put the water heater in operation
3. Press the reset button down for longer than 5 seconds; L
appears in the display. Pressing the
reset button again, C 00 appears in the display.
Press the + button to select the burner module to be run
at full load
Burner module 1
Burner module 2
Burner module 3
Burner module 4
All burner modules simultaneously
Burner module 2 not present
Press the reset button to choose the desired burner
module. Th e burner can now function at full load or low load
using the + and – buttons respectively. Th e actual burner
capacity appears in the display alternately with:
Burner module 1 full load
Burner module 1 low load
Select full load with the + button, when the actual burner
capacity is above 90%, the CO 2 percentage can be
measured and set.
Fig 15 – Setscrews
4. Measure the CO 2 percentage and compare it with table
1 (page 33). Th e CO 2 percentage can be adjusted using
the "Full Load" Setscrew (A) on the gas regulation unit
(see Fig 15). Th e CO 2 percentage can be increased by
turning the setscrew to the left.
5. Now check the CO 2 percentage at low load.

CONTROL AND ADJUSTMENT AT LOW LOAD

1. Select low load with the – button. When the actual
burner capacity is above 25%, the CO 2 percentage can
be measured and set.
2. Measure the CO 2 percentage and check it against table
1 (page 33). Th e CO 2 percentage can be adjusted using
the "Low Load" Setscrew (b) (2mm Alan Key) on the gas
regulation unit (see Fig 15).
Th e CO 2 percentage can be increased by turning the
setscrew to the right.
3. Check the CO 2 percentage at full load again. If there
is another adjustment at full load, check it at low load
again.
4. Press the reset button. A new burner module can now
be selected using the + and – buttons. Th e heater is
brought into operation again by repeatedly pressing on
the – button until C 00 appears in the display. Press
the reset button again and the display switches back to
normal.
NB: IF THE UNIT IS LEFT IN THE COMMISSIONING MODE
BY MISTAKE, AFTER 10 MINUTES, THE SOFTWARE WILL
AUTOMATICALLY SWITCH THE APPLIANCE BACK TO
NORMAL OPERATION.

DECOMMISSIONING

Turn the electricity supply off. Th en, turn off the gas tap
in the supply pipe. Th e water heater must be empty when
there is a risk of freezing. Please note: if the electricity
supply remains switched off for a long period, the self test
of the control no longer works. Th is happens once every
24 hours and activates pumps momentarily to prevent the
pumps from sticking, amongst other things.
MAXXfl o Water Heater
INSTRUCTIONS FOR COMMISSIONING • SECTION 5 35 35