Bard PH10481 Installation Instructions Manual - page 19

Manual 2100-354

Page

17

THERMOSTAT INDICATOR LAMPS

The red lamp marked “EM. HT.” comes on and stays on

whenever the system switch is placed in Em. Ht. position.

The green lamp marked “Check” will come on if there is

any problem that prevents the compressor from running

when it is supposed to be.

EMERGENCY HEAT POSITION

The operator of the equipment must manually place the

system switch in this position.  This is done when there is a

known problem with the outdoor section, or when the green

“Check” lamp comes on indicating a problem.

TRANSFORMER TAPS

230/208V, 1 phase and 3 phase equipment employ dual

primary voltage transformers.  All equipment leaves the

factory wired on 240V tap.  For 208V operation, reconnect

from 240V to 208V tap.  The acceptable operating voltage

range for the 240 and 208V taps are:

TAP

 RANGE

 240

253 – 216

 208

220 – 187

NOTE: The voltage should be measured at the field

power connection point in the unit and while the

unit is operating at full load (maximum

amperage operating condition).

COMPRESSOR CUTOFF THERMOSTAT

and OUTDOOR THERMOSTAT WIRING

Heat pump compressor operation at outdoor temperatures

below 0° F are neither desirable not advantageous in terms

of efficiency.  Since most equipment at time of

manufacture is not designated for any specific destination

of the country and most of the equipment is installed in

areas not approaching the lower outdoor temperature

range, the compressor cutoffs are not factory installed.

Outdoor thermostats are available to hold off various

banks of electric heat until needed as determined by

outdoor temperature.  The set point of either type of

thermostat is variable with geographic region and sizing of

the heating equipment to the structure.  Utilization of the

Heating Application Data and the heat loss calculation of

the building are useful in determining the correct set

points.  Refer to Installation Instructions of CMH-14

Outdoor Thermostat Kit for more information.

MIS-1188

FIGURE  10

UNIT 24V TERMINAL BOARD ( 5 THRU 10 KW)