Manual 2100-347F
Page
16 of 24
ELECTRIC HEAT HOLD-OFF
(See Figures 12 and 13)
In other applications, it is desirable to disable the
operation of the electric heat until outdoor temperatures
have reached a certain design point. This won't allow
the electric heat to come on as second stage heating
unless the outdoor temperature is below the set point of
the outdoor thermostat. This is done to maximize
efficiency by utilizing the heat pump to bring the
conditioned space temperature up, rather than cycling
on the electric heat due a second stage call for heat from
the thermostat on start-up coming off a night set-back
condition or someone increasing the thermostat set
point. (NOTE: Some programmable thermostats do
have a built-in time delay for pulling in second stage
heat when coming off set-back conditions.)
FIGURE 12
ELECTRIC HEAT HOLD-OFF WIRING
4 – 10KW 1 PH – 6 & 9KW 3 PH
FIGURE 13
ELECTRIC HEAT HOLD-OFF WIRING
15 – 20KW 1 PH AND 3 PH
