Ariston EGIS PREMIUM S 25, Installation And Servicing Instructions

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boiler protection devices
Anti-frost Device.
The anti-frost function acts on the central heating fl ow temperature pro-
be, independently from other regulations, when the electrical supply is
turned on.
If the primary circuit temperature falls below 8°C the pump will run
for 2 minutes.
After the two minutes of circulation ( fi xed) the boiler will check the
following:
a) if the central heating fl ow temperature is > 8°C, the pump stops;
b) if the central heating fl ow temperature is between 4 and 8°C, the
pump will run for another two minutes;
c) if the central heating fl ow temperature is < 4°C, the burner will fi re
(heating position) at minimum power until the temperature rea-
ches 33°C, the burner will go out and the pump will continue to
run for two minutes.
If the fl ow temperature remains between 4-8°C the pump will con-
tinue to run for two minutes for a maximum of 10 times unless a
temperature above 8°C is detected in the central heating fl ow, after
this the the burner will fi re. If lockout is caused by overheat the bur-
ner is kept OFF.
The anti-frost device activates only when (with the boiler operating
correctly):
- the system pressure is correct;
- the boiler is electrically powered;
- there is a supply of gas.
Important
If this shutdown occurs frequently, contact an authorised Technical Service
Centre for assistance. For safety reasons, the boiler will permit a maximum of 5
resets in 15 minutes (5 presses of the RESET button); at the 6th attempt within
this 15-minute period the boiler will shut down and may only be operated
again after the electricity supply has been disconnected. If the shutdown is
occasional or an isolated event, this is not a problem.