Chaffoteaux MIRA SYSTEM 24 CF [8/20] Operating

PRESSURISATION (fig. 12)

Heating circuit and tank:

- open cold water tap 34

- check that the heating flow 31, heating backflow 35 and tank backflow 32 taps (compy system plus) are open

- open filling tap 36

- close the tap again when the needle of pressure gauge 19 (fig. 3) is at the pressure specified in § 3

- drain the installation and re-establish the pressure

Gas circuit

- open gas tap 33

- flush the gas circuit

- check the whole gas line for leaks

SETTINGS

The boiler is supplied with all the adjusting knobs set to OFF (fig. 13) and the potentiometers turned fully clockwise. It is

possible to adjust these settings if required.

In that case, it is necessary to open the electronic control unit.

Switch off the boiler, remove the casing and open the unit by pressing the 2 tabs P (fig. 10). The adjusting knobs are on the

electronic circuit board behind blanking cover E (fig. 11).

- A1 is used to set the Heating Anti-cycle Time (HAT) period to 30 seconds or 3 minutes

HAT: period during which restarting the burner is prohibited during a heating regulation phase

- A2 allows the speed of the pump in heating mode to be selected (high speed or adaptive speed)

- A3 is used to adjust the heating temperature setting to 40 °C irrespective of the position of heating temperature adjustment

knob 22 (fig. 3)

- A4 enables operation in modulating heating mode or all or nothing mode

- B1 allows the duration of post-circulation in heating mode to be adjusted

- B2 allows the domestic hot water time delay (TIC) to be adjusted

- B3 not used

- B4 not used

N.B. After a power cut or a board reset, the HAT is cancelled for 3 minutes.

- P1: potentiometer for reducing the heating power

(see table page 9)

- P2: not used

- P3: not used

Once adjustments have been made, replace blanking cover E, close the control unit cover and refit the casing.

7. Operating

Fig. 12