12/30/2020 11
EI916
Operational Indicators
Green LED
– on control board.
Full on = low voltage present and okay, micro controller is functioning, etc.
One pulse = electric heating element is active (set point is still controlling actual element on/off).
Two pulses = bad outlet temperature sensor.
Three pulses = control hi-limit open.
R to W closed contact
– external switch device.
Fan is running.
Inlet damper is opening and held open.
-
Inlet damper is spring close.
Control board – heat active (set point is still controlling actual element on/off).
Fan relationship to electric heating elements
– fan comes on immediate with R to W contact. There is
a 30-second delay before elements turn on (outlet sensor needs to measure inlet air, not room air). The
fan also purges the inside elements and warm air after R to W is open for 60 seconds.
Hi-limit, manual reset
– all operations seem normal, but the heating element power is interrupted.
The reset button is in the hinged door compartment, on control box divider.
Auto reset hi-limits
– there are two.
Temperature control, at fan inlet, this is set for an approximate 90° F outlet temperature. It is in
the low voltage logic control circuit. LED will show 3 pulses.
Comment – this is in addition to the outlet temperature sensor mounted within the discharge duct
which responds to the set point temperature dial.
Element current carrying leg – within the sheet metal housing/inside deflectors, this is a safety hi-
limit in case there is a fan failure or major inlet air restriction.
Disconnected or bad detected sensor
– LED will show two pulses. The electric elements or heat active
is at 100% on, follows the R-W input. With an inactive duct sensor the electric elements are no longer
controlled at set point.
