Specifications

ManualsBrandsCarrier ManualsThermostatAPOLLO CONTROL 50HJQ004-016

SEQUENCE OF OPERATION

50HJQ004-012 Units

COOLING, UNITS WITHOUT ECONOMIZER — When

thermostat calls for cooling, terminals G and Y1 are energized.

The indoor-fan contactor (IFC), reversing valve solenoid

(RVS1) and compressor contactor no. 1 (C1) are energized and

indoor-fan motor, compressor no. 1, and outdoor fans start. The

outdoor-fan motor(s) run continuously while unit is cooling.

HEATING, UNITS WITHOUT ECONOMIZER (Sizes

004-007) — Set system switch at AUTO. or HEAT position.

Set thermostat at desired temperature.

When the thermostat calls for heat, the IFC, outdoor-fan

contactor (OFC), and compressor contactor are energized. The

RVS is deenergized and switches position, and the indoor fan,

outdoor fan, and compressor are energized.

If the thermostat calls for a second stage of heat, the heater

contactor (HC) is energized and starts the electric heaters.

When the space temperature approaches the heating tem-

perature set point, heating stages cycle off.

HEATING, UNITS WITHOUT ECONOMIZER (Sizes

008,012) — Upon a request for heating from the space

thermostat, terminal W1 will be energized with 24 v. The IFC,

outdoor-fan contactor (OFC), C1, and C2 will be energized.

The reversing valves deenergize and switch position and the

indoor fan, outdoor fan, compressor no. 1, and compressor

no. 2 are energized.

If the space temperature continues to fall while W1 is

energized, W2 will be energized with 24 v, and the heater

contactor(s) (HC) will be energized, which will energize the

electric heater(s).

When the space thermostat is satisfied, W2 will be

deenergized first, and the electric heater(s) will be deenergized.

Upon a further rise in space temperature, W1 will be

deenergized, and the compressors will turn off.

COOLING, UNITS WITH DURABLADE ECONO-

MIZER — When the outdoor-air temperature is above the

outdoor-air thermostat (OAT) setting and the room thermostat

calls for cooling, compressor contactor no. 1 is energized to

start compressor no. 1 and the outdoor-fan motor(s). RVS1

(reversing valve solenoid) is energized. The indoor-fan motor

is energized and the economizer damper moves to the

minimum position. Upon a further call for cooling, compressor

contactor no. 2 will be energized (50HJQ008,012), starting

compressor no. 2. RVS2 is energized. After the thermostat is

satisfied, the damper moves to the fully closed position. When

using continuous fan, the damper moves to minimum position.

When the outdoor-air temperature is below the OAT setting

and the thermostat calls for cooling, the economizer dampers

move to the minimum position. If the supply-air temperature is

above 57 F, the damper continues to open until it reaches the

fully open position or until the supply-air temperature drops

below 52 F.

When the supply-air temperature falls to between 57 F and

52 F, the damper will remain at an intermediate open position.

If the supply-air temperature falls below 52 F, the damper will

modulate closed until it reaches the minimum position or until

the supply-air temperature is above 52 F. When the thermostat

is satisfied, the damper will move to the fully closed position.

When using continuous fan, the damper moves to minimum

position.

If the outdoor air alone cannot satisfy the cooling require-

ments of the conditioned space, economizer cooling is integrated

with mechanical cooling, providing second-stage cooling.

Compressor no. 1, reversing valve solenoid (RVS1) and the

outdoor fan will be energized and the position of the economizer

damper will be determined by the supply-air temperature.

Compressor no. 2 (50HJQ008,012) is locked out.

When the second stage of cooling is satisfied, the compres-

sor, RVS2, and outdoor-fan motor(s) will be deenergized.

The damper position will be determined by the supply-air

temperature.

When the first stage of cooling is satisfied, the damper will

move to fully closed position. When using continuous fan, the

damper moves to minimum position.

COOLING UNITS WITH ECONOMI$ER (EconoMi$er,

Johnson Actuator, was produced from Unit Serial Numbers

from 2009Gxxxxx to 0702Gxxxxx) (Sizes 004-007) — When

the outdoor-air temperature (OAT) is above the ECON SP set

point and the room thermostat calls for Stage 1 cooling, termi-

nals G and Y1 are energized. The indoor-fan contactor (IFC),

reversing valve solenoid (RVS1) and compressor contactor

no. 1 (C1) are energized and indoor-fan motor, compressor

no. 1, and outdoor fans start. The EconoMi$er damper

modulates to minimum position. The outdoor-fan motor(s) run

continuously while unit is cooling. After the thermostat is

satisfied, the damper modulates to the fully closed position

when the IFM is deenergized.

When the OAT is below the ECON SP setting and the room

thermostat calls for Stage 1 cooling (R to G + Y1), the

EconoMi$er modulates to the minimum position when the

IFM is energized. The EconoMi$er provides Stage 1 of cooling

by modulating the return and outdoor-air dampers to maintain

a 55 F supply air set point. If the supply-air temperature (SAT)

is greater than 57 F, the EconoMi$er modulates open, allowing

a greater amount of outdoor air to enter the unit. If the SAT

drops below 53 F, the outdoor air damper modulates closed to

reduce the amount of outdoor air. When the SAT is between 53

and 57 F, the EconoMi$er maintains its position.

If outdoor-air alone cannot satisfy the cooling requirements

of the conditioned space, and the OAT is above the MECH

CLG LOCKOUT set point, the EconoMi$er integrates free

cooling with mechanical cooling. This is accomplished by the

strategies below.

NOTE: Compressor has a 2-minute Minimum On, Minimum

Off, and Interstage delay timer.

1. If Y1 is energized, and the room thermostat calls for Y2

(2-stage thermostat), the compressor, RVS1 and OFM are

energized. The EconoMi$er damper is maintained at its

current position.

2. If Y1 is energized for more than 20 minutes, and Y2 is

not energized (whether or not a 2-stage thermostat is

used), the compressor, RVS1 and OFM are energized.

The EconoMi$er damper is maintained at its current

position.

3. If Y1 is energized, the compressors and RVS1 are already

energized (see Step 2) and the room thermostat calls for

Y2, the compressor continues to operate.

4. If compressor and RVS1 are energized and the thermostat

is satisfied, the compressor, RVS1, the OFM, and IFM are

deenergized and the EconoMi$er modulates closed.

When the OAT is below the MECH CLG LOCKOUT set

point, the compressors remain off.

COOLING, UNITS WITH ECONOMI$ER (EconoMi$er,

Johnson Actuator, was produced from Unit Serial Numbers

from 2009Gxxxxx to 0702Gxxxxx) (Sizes 008-014) — When