How To Set Your Hot Water Set Temperature; Boiler Service Reminder; Countdown To Service / When Service Is Due - Honeywell Y9420S User Manual

FINE TUNING YOUR ST9420C

How to set your Hot Water Set Temperature

If your system includes a CS92A hot water sensor on your hot water storage tank,
you will be able to set the hot water temperature you require at the ST9420C
programmer. The temperature is set to 60°C at the factory, but can be set anywhere
between 40°C and 85°C, depending on the application. The setting is changed by
entering Installer Mode and modifying parameter number 8 to give the required set
temperature.

BOILER SERVICE REMINDER

If your house is rented, by Law, your gas boiler should be inspected once a year
to ensure it is operating safely. Your ST9420C Programmer has a range of features
designed to help make sure this service is carried out at the correct time. These
features will be programmed by your Installer, Maintenance Engineer, or Landlord.
• If it has been set to do so, ST9420C will display a message on the screen to
remind you that a boiler service is due.
• If the service is overdue, the Programmer may switch off the heating system, to
ensure your safety. If this happens you must arrange an immediate service visit.
Contact details should be listed on page 35 of this guide, in the section Boiler &
System Service Log.
• A contact telephone number may also have been programmed into the ST9420C.
If so, a message will appear on the LoT™ Display indicating the number you
should call.
Countdown to Service
Your ST9420C can indicate a countdown for the
number of days until your service is due. This
message will appear on the screen every few
seconds, to give you an opportunity to schedule
a service visit.
When Service is Due
When your boiler service is OVERDUE the words
"SERVICE DUE" will continue to flash on your
screen, and you should arrange an immediate
service visit.
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