andrews CWH120/200, Installation, Operation And Maintenance Manual

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MAXXflo Water Heater
34 34
FILLING THE WATER HEATER
1. Check that the tank drain tap is closed
2. Check that the return valve in the 28mm pipe (close to
the drain tap) is open
3. Open the main water tap, and then all warm water
drainage points so that air present in the installation
and water heater can escape
4. Fill the water heater by turning on the cold water supply
tap. The water heater is full once water is flowing out of
all the warm water drainage points
COMMISSIONING
To commission using Propane, turn the high
setting screw completely clockwise on each
burner before starting the heater. Then, start up
each heater and turn the high setting screw anti-
clockwise until the burner ignites. Then, proceed
as per the following instructions.
1. Before the water heater can be used, it must be checked
that:
• The water heater is completely full of water
• The gas pipes have been purged
• The electricity supply to the appliance is switched on
• The phase and neutral are correctly connected to the
appliance
2. Open the appliance’s gas tap
3. Switch the electricity on with the power switch on the
control panel.
The water heater now searches for what burner modules
are present. When these are detected, the green LED for
the corresponding burner module begins to flash. When
all burner modules have been detected, they are started
up one by one. When the burner module is operational, the
green LED is lit permanently.
CO2 ADJUSTMENT
The correct proportion of gas and air can be controlled
based on the CO2 percentage in the flue gasses. This
control needs to be done at full load and low load.
Every burner module has CO2 measuring point for the
measurement, see Fig 9. Table 1 shows the value of the CO2
percentage at full load and low load.
Table 1: CO2 Percentage
Gas Type Full Load Low Load
Natural Gas 8.8% 8.3%
Propane 9.8% 9.2%
Fig 14 – Measuring Point
SECTION 5 • INSTRUCTIONS FOR COMMISSIONING