Filter Indicator - Honeywell T8665C EnergyPro Owner's Manual

Filter Indicator

F IL T E R E X P IR A T IO N IN D IC A T O R
Your thermostat monitors the amount of time
the fan is running and lets you know when to
replace the filter, based on the number of fan
run-time days you select. On expiration,
thermostat displays "Filter."
One fan run-time day equals 24 fan run-time
hours. (If fan is on only one-
third of the time each day, it
takes three days to deduct
one fan run-time day.)
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