Ariston A/23 MFFI, A/27 MFFI, 47-116-12 Ignition Failure, Circulation Failure, Overheating

3.6Combustion Analysis

3.7Fume Discharge Monitoring

3.8Boiler Safety Systems

G20 5.5 mm c.a.

G25 4.5 mm c.a.

G30-31 1.8 mm c.a.

-the potentiometer for the maximum thermal power for the heating system, maximum thermal power setting (factory set at the maximum value, unless indicated otherwise on the adhesive sticker located in proximity to the potentiometer);

-The connection for the diagnostic device (TCS-TCS2).

The boiler is designed to make it easy to analyse the combustion by-products.

Using the especially designed apertures, readings can be taken on the temperature of the combustion by-products and of the combustion air, as well as of the concentrations of O2 and CO2, etc.

The best maximum-power test conditions for the heating system are when the selector “C” is turned to the flue analysis setting.

The discharge/ventilation of the exhaust fumes can be monitored to check for losses in general pressure in the system. This is done to eliminate the cause of lighting failure with the main burner not indicated by a shutdown status.

With a differential manometer connected to the test socket on the combustion chamber, the DP value for the air pressure switch can be taken. The measured value should not be less than 10 mbar under maximum thermal power conditions (with the knob “C” on the flue test setting) in order for the unit to function properly and without interruption.

The boiler is equipped with the following safety systems (see section 3.3 for references):

1 - Ignition Failure

This control signals an ignition failure on the burner 7 seconds after a lighting failure. The L.E.D. “B”.will turn on to signal the shutdown status.

The system can be reset by pressing and releasing the button “A” after checking to make sure that the gas valve is open. Repeat this process until the burner lights.

2 - Circulation Failure

This control signals that the safety pressure switch on the primary circuit has not sensed a pressure of at least 1 bar within 40 seconds of the activation of the circulation pump, it shuts off the boiler and lights the L.E.D. “D”. The system can be reset (after the pressure has been brought up to the proper level) by using the On/Off switch “L”.

3 - Overheating

This control shuts off the boiler in the case where the primary circuit reaches a temperature in excess of 110°C. The L.E.D. “G” will come on to signal this shut

20 B023