Subject to change without notice.
6
PHH50–150G3
REV — 6/15/20
THERE IS STILL POWER AT THE UNIT’S
CIRCUIT BREAKER .
5. The unit has a built in Selector Switch (SS)
OFF/FAN/Heat in the control panel. Make
sure the SS is set to the OFF position before
applying power to the unit. See Figure 4 –
Control Panel for reference.
Figure 3 – Control Panel
6. Install the proper size flexible supply and
return ducting to the unit in as straight a
manner as possible. Avoid making excessive
turns or turns greater than 45° as this will
increase restriction on the blower and cause
a decrease in total air flow. Excessive bends
or kinks may cause the heaters to short cycle.
CAUTION: USE HIGH TEMPERATURE DUCTS
RATED FOR 325°F .
CAUTION: Before applying power make
certain the unit is connected to Earth ground .
OPERATING INSTRUCTIONS
Switch the main power disconnect at the power
supply to the ON position. Internal wiring connects
the input power at the unit to a circuit breaker on
board the unit, which also serves as a service
disconnect switch for the unit. Switch the unit’s
circuit breaker to the “ON” position to supply
power to the unit.
Once the power is “ON”, the Power LED should
illuminate. If the Power LED is illuminated, the unit
is ready for operation. If not, check the voltage
being supplied to the unit at the main power
source. Disconnect (turn OFF) the unit’s circuit
breaker and the main power at the power source
when checking for voltage.
CONTROLS
Blower Control:
When the Circuit Breaker (CB) is in the ON
position, switching the SS to the ON position will
start the supply air blower.
Placing the SS to the heat position will energize
the heater banks. The thermostat senses the
Return Air (RA) and switches heaters on or off to
maintain setpoint.
UNIT COMPONENTS
Heater Time Delays
The unit is manufactured with internal time delays
to protect the system from overloading the supply
power with a large inrush all at the same time.
