Ariston A/27 MFFI GAS Adjustments, Draining the System, Limescale Build-up, Safety Shut-off

		off status. After the system has been allowed to cool, the system can be reset
		by pressing the button “A”.
		4 - Limescale Build-up
		This is an indirect control (actuated through the regulation of the temperature in
		the primary heat exchanger) on the formation of limescale in the secondary
		heat exchanger. Regardless of the flow rate and the temperature in the circuit
		for the domestic hot water, the temperature is limited to 62°C.
		5 - Safety Shut-off
		At the start of every lighting phase, the P.C.B. performs a series of internal
		controls. If a malfunction occurs, the boiler will shutdown until the problem has
		been resolved.
3.9	Draining the System	Draining the heating system.
		The heating system must be emptied as follows:
		- Turn off the boiler;
		- Open the drain valve for the system and place a container below to catch the
		water that comes out;
		- Empty the system at the lowest points (where present). If you plan on not
		using the heating system for an extended period of time, it is recommended
		that you add antifreeze with an ethylene glycol base to the water in the
		heating lines and radiators if the ambient temperature drops below 0°C during
		the winter.
		This makes repeated draining of the entire system unnecessary.

Draining the domestic hot water system.

Whenever there is the danger of the temperature dropping below the freezing point, the domestic hot water system must be drained as follows:

- Turn off the general water valve for the household plumbing system; - Turn on all the hot and cold water taps;

- Empty the remaining water from the lowest points in the system (where present).

4.GAS ADJUSTMENTS

CATEGORY II2H3+		Methane Gas	Liquid Butane Gas	Liquid Propane Gas
		G20	G30	G31
Lower Wobbe Index (15°C;1013mbar)	MJ/m 3h	45.67	80.58	70.69
Nominal Delivery Pressure	mbar	20	30	37
Minimum Delivery Pressure	mbar	17	20	25
A/23 MFFI
Main Burner: n. 13 jets (ø)	mm	1.,25	0.72	0.72
Consumption (15°C; 1013mbar)	mc/h	2.72	----	----
Consumption (15°C; 1013mbar)	Kg/h	----	2.02	2.02
Gas Cock Outlet Pressure
min - max	mbar	11.4- 2.0	27.5 (*) - 5.2	35.0 (*) - 7.0
A/27 MFFI
Main Burner: n. 15 jets (ø)		1.25	0.72	0.72
Consumption (15°C; 1013mbar)	mc/h	3.16	----	----
Consumption (15°C; 1013mbar)	Kg/h	----	2.35	2.32
Gas Cock Outlet Pressure:
max - min	mbar	11.6-2.2	(*) - 4.8	(*) - 6.0

(1mbar = 10,197 column of water)

The outlet pressure of the gas cock is obtained by completely loosening the screw on the solenoid. The maximum pressure of the gas to the burner will be equal to the nominal delivery pressure minus the head loss within the gas valve.

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