Utility Interface - Bryant Evolutiont 286A Installation Instructions Manual

Evolution series heat pumps with puron refrigerant 2 to 5 nominal tons (sizes 024 to 060)

Hide thumbs

Table Of Contents

Table of Contents

Enlarged version

Start- -Up

CAUTION

UNIT OPERATION AND SAFETY HAZARD

Failure to follow this caution may result in minor personal

injury, equipment damage or improper operation.

Observe the following:

1. Do not overcharge system with refrigerant.

2. Do not operate unit in a vacuum or at negative pressure.

3. Do not disable low pressure switch

4. Dome temperatures may be hot.

CAUTION

PERSONAL INJURY HAZARD

Failure to follow this caution may result in personal injury.

Wear safety glasses, protective clothing, and gloves when

handling refrigerant.

CAUTION

ENVIRONMENTAL HAZARD

Failure to follow this caution may result in environmental

damage.

Federal regulations require that you do not vent

refrigerant to the atmosphere. Recover during system

repair or final unit disposal.

Follow these steps to properly start up the system:

1. After system is evacuated, fully back seat (open) liquid and

vapor service valves.

2. Unit is shipped with valve stem(s) front seated (closed) and

caps installed. Replace stem caps after system is opened to

refrigerant flow (back seated). Replace caps finger- -tight and

tighten with wrench an additional 1/12 turn.

3. Close electrical disconnects to energize system.

4. Set room thermostat or User Interface at desired temperat-

ure. Be sure set point is below indoor ambient temperature

and is set low enough to energize desired stage.

5. Set room thermostat or User Interface to COOL and fan

control to ON or AUTO mode, as desired. Operate unit for

15 minutes. Check system refrigerant charge.

NOTE: Non- -communicating (non- -Evolution) Bryant thermostats

are equipped with a 15- -minute staging timer. This timer prevents

the two- -stage system from operating at high stage until unit has

been operating in low stage for 15 minutes, unless there is at least a

±5°F (±2.8°C) difference between room temperature and thermostat

set point. To force high stage (after a minimum of 2 minutes in low

stage), adjust the set point at least ±5°F (±2.8°C) below room

ambient.

6. Set room thermostat or User Interface to HEAT or COOL

and fan control to AUTO or ON, as desired. Wait for appro-

priate time delay(s). Operate unit for 15 minutes. Check re-

frigerant charge.

System Functions and Sequence of Operation

The outdoor unit control system has special functions. The

following is an overview of the two- -stage control functions:

Cooling and Heating Operation

The 286A and 288A (containing circuit board HK38EA015 or

newer) models utilize either a standard indoor thermostat or

Evolution Communication User Interface. With a call for first

stage cooling, the outdoor fan, reversing valve, and low stage

compressor are energized. If low- -stage cannot satisfy cooling

demand, high- -stage cooling is energized by the second stage of

indoor thermostat or User Interface. After second stage is satisfied,

the unit returns to low- -stage operation until first stage is satisfied

or until second stage is required again. When both first stage and

second stage cooling are satisfied, the compressor will shut off. The

reversing valve will remain energized until the control board power

is removed or a call for heating in initiated. With a call for heating,

the outdoor fan and compressor are energized. The compressor will

operate in high or low stage operation, as needed to meet the

heating demand. When the heating demand is satisfied, the

compressor and fan will shut off. The reversing valve is

de- -energized in the heating mode.

NOTE:

When two- -stage unit is operating at low- -stage, system

vapor (suction) pressure will be higher than a standard single- -stage

system or high- -stage operation.

NOTE:

Outdoor fan motor will continue to operate for one

minute after compressor shuts off, when outdoor ambient is greater

than or equal to 100°F. This reduces pressure differential for easier

starting on next cycle.

NOTE: On 286A models, if unit has not operated within the past

12 hours, or following a unit power- -up, upon the next thermostat

high- - or low- -stage demand, unit operates for a minimum of 5

minutes in high- -stage.

With non- -communicating (non- -Evolution) systems, with first

stage of cooling, Y1 and O are powered on; and with second stage

of cooling, Y1, Y2, and O are on. For these systems, with first

stage of heating Y1 is on and for second stage of heating, Y1 and

Y2 are on. When the reversing valve is energized, O is powered

on.

Communication and Status Function Lights

For Evolution Control only, Green communications (COMM)

Light

A green LED (COMM light) on the outdoor board (see Fig. 6)

indicates successful communication with the other system

products. The green LED will remain OFF until communication is

established. Once a valid command is received, the green LED will

turn ON continuously. If no communication is received within 2

minutes, the LED will be turned OFF until the next valid

communication.

Amber Status Light

An amber colored STATUS light is used to display the operation

mode and fault codes as specified in the troubleshooting section.

See Table 6 for codes and definitions.

NOTE: Only one code will be displayed on the outdoor unit

control board (the most recent, with the highest priority).