The display should show:
5. Check the correct operation of the timer (if fitted) and all
other system controls. Operate each control separately
and check that the main burner responds.
WATER CIRCULATION SYSTEM
1. With the system cold, check that the initial pressure is
correct to the system design requirements.
For pre-pressurised systems, this should be 1.0 bar.
2. With the system hot, examine all water connections for
soundness. The system pressure will increase with
temperature rise but should not exceed 2.5 bar.
3. With the system still hot, turn off the gas, water and
electricity supplies to the boiler and drain down to
complete the flushing process.
Note.
A flushing solution should be used during the flushing
procedure. Flushing solutions: Fernox Superfloc, Sentinel
X300 (new systems) or X400 (existing systems).
4. Refill and vent the system, add inhibitor, clear all air
locks and again check for water soundness.
5. Reset the system initial pressure to the design
requirement.
6. Balance the system.
7. Check the condensate drain for leaks and check that it is
discharging correctly.
8. Finally, set the controls to the User’s requirements.
The pump will operate briefly as a self-check once every 24
hours in the absence of any system demand.
WATER TEMPERATURES
Temperatures can be selected using the CH and DHW
thermostats.
2.35 GENERAL CHECKS
1. Fully open all DHW taps in turn and ensure that water
flows freely from them.
The display should show:
2. Close all taps except the furthest one from the boiler and
check that the boiler is firing at maximum rate. This is factory
set to give a DHW temperature rise of approximately 35
o
C
at the flow rate stated on page 8 under “operation”.
3.
Reduce the DHW draw-off rate to about 3 l/min (0.7 gpm) and
check that the boiler modulates to deliver DHW at approximately
65
o
C.
4. Close the DHW tap and check that the main burner
extinguishes. The pump should overrun for 60 seconds.
When the pump stops the display should show:
Note.
On systems in excess of 2 bar inlet pressure a water
pressure governor may be required to prevent water noise.
CH & DHW MODES
1. Ensure that the CH external controls are calling for heat.
2. Fully open a DHW tap and check that hot water is
delivered.
The display should show:
Target 65°C
Menu
Mode
Ready
Radiator Target
60°C
Hot Water Priority
On at 65°C
Gas Rate
1. Check the boiler gas rate when the boiler is at full DHW
output.
2. Check at the gas meter, with no other appliance in use.
Refer to Tables 2 & 3 for gas rates.
3. Close the DHW tap.
4. Set the central heating external controls to OFF. The
burner should go off and the pump continue to run for
two minutes.
Make the following checks for correct operation in:
Due to system variations and seasonal temperature
fluctuations DHW flow rates/temperature rise will vary,
requiring adjustment at the draw off tap : the lower the rate
the higher the temperature, and vice versa.
Refer to Section
1.17
Refer to Section
1.18
Boiler Target 65°C
Menu
Mode
Ready
Radiator Target
60°C
Room Thermostat or
Timer Off
On at 65°C
Target 60°C
Menu
Mode
Ready
Radiator Target
60°C
Room Thermostat or
Timer Off
Ready
Target 60°C
Preheat
Menu
Mode
Ready
Off
Radiator Target
60°C
Room Thermostat or
Timer Off
Ready
Refer to Section
1.10
Temperature Knob
CH Flow Temp
DHW Outlet
Setting
o
C
o
C
Max
80
65
Min
30
40
36
Installation and Servicing
Section 2 - Installation
INST
ALLA
TION
