Carrier WEATHERMASTER 48/50Z030-105 User Manual

Page 76

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OAQ Low Reference (Configuration

IAQ

AQ.S.R

OQ.R.L) — This is the reference that will be used with a

non-Carrier OAQ sensor that may have a different characteris-

tic curve. It represents the CO

2

level at 4 mA.

OAQ High Reference (Configuration

IAQ

AQ.S.R

OQ.R.H) — This is the reference that will be used with a non-

Carrier OAQ sensor that may have a different characteristic

curve. It represents the CO

2

level at 4 mA.

Diff. IAQ Responsiveness (Configuration

IAQ

AQ.SP

IAQ.R) — This is the configuration that is used to select the

IAQ response curves as shown in Fig. 12.
PRE-OCCUPANCY PURGE — The control has the option

for a pre-occupancy purge to refresh the air in the space prior to

occupancy.

This feature is enabled by setting Configuration

IAQ

IAQ.P

IQ.PG to Yes.

The IAQ Purge will operate under the following conditions:

IQ.PG is enabled

• the unit is in the unoccupied state

• Current Time is valid

• Next Occupied Time is valid

• time is within two hours of the next occupied period

• time is within the purge duration (Configuration

IAQ

IAQ.P

IQ.P.T)

If all of the above conditions are met, the following logic is

used:

If OAT >= IQ.L.O and OAT <= OCSP and economizer is
available then purge will be enabled and the economizer

will be commanded to 100%.

Else, if OAT < IQ.L.O then the economizer will be posi-

tioned to the IAQ Purge LO Temp Min Pos (Configuration

IAQ

IAQ.P

IQ.P.L)

If neither of the above are true then the dampers will be

positioned to the IAQ Purge HI Temp Min Pos (Configuration

IAQ

IAQ.P

IQ.P.H)

If this mode is enabled the indoor fan and heat interlock

relay (VAV) will be energized.
IAQ Purge (Configuration

IAQ

IAQ.P

IQ.PG) — This

is used to enable IAQ pre-occupancy purge.
IAQ Purge Duration (Configuration

IAQ

IAQ.P

IQ.P.T) — This is the maximum amount of time that a purge

can occur.
IAQ Purge Lo Temp Min Pos (Configuration

IAQ

IAQ.P

IQ.P.L) — This is used to configure a low limit for

damper position to be used during the purge mode.
IAQ Purge Hi Temp Min Pos (Configuration

IAQ

IAQ.P

IQ.P.H) — This is used to configure a maximum po-

sition for the dampers to be used during the purge cycle.
IAQ Purge OAT Lockout Temp (Configuration

IAQ

IAQ.P

IQ.L.O) — Nighttime lockout temperature below

which the purge cycle will be disabled.
OPTIONAL AIRFLOW STATION — The ComfortLink™

controls are capable of working with a factory-installed option-

al airflow station that measures the amount of outdoor air enter-

ing the economizer. This flow station is intended to measure

ventilation airflows and has a limitation as to the maximum

flow rate it can measure. The limits are 18,000 cfm for sizes

030-050 and 31,000 cfm for sizes 055-105.

All configurations for the outdoor airflow station can be

found in the Configuration

ECON

CFM.C, sub-menu.

For this algorithm to function, the Outdoor Air Cfm Sensor

Configuration (OCF.S.) must be enabled.
There are three set point configurations:
O.C.MN — Econ OACFM DCV Min Flow

O.C.MX — Econ OACFM DCV Max Flow
O.C.DB — Econ OACFM MinPos Deadbd

When the outdoor air cfm sensor is enabled, the Economizer

Min.Position (Configuration

IAQ

DCV.C

EC.MN) and

the IAQ Demand Vent Min.Pos (Configuration

IAQ

DCV.C

IAQ.M) will no longer be used. During vent periods,

the control will modulate the damper to maintain the outdoor

air intake quantity between O.C.MX and O.C.MN. The indoor

air quality algorithm will vary the cfm between these two

values depending on Configuration

IAQ

AQ.SP

DAQ.L

and the Configuration

IAQ

AQ.SP

DAQ.H set points

and upon the relationship between the IAQ and the outdoor air

quality (OAQ).

The economizer’s OA CFM Minimum Position Deadband

(O.C.DB) is the deadband range around the outdoor cfm

control point at where the damper control will stop, indicating

the control point has been reached. See the Economizer section

for more information.

Humidification —

The Z Series ComfortLink controls

can control a field-supplied and installed humidifier device.

The ComfortLink controls provide two types of humidification

control: A discrete stage control (via a relay contact) and a pro-

portional control type (communicating to a LEN actuator). The

discrete stage control is used to control a single-stage humidifi-

er, (typically a spray pump). The proportional control type is

typically used to control a proportional steam valve serving a

steam grid humidifier.

The ComfortLink controls must be equipped with a controls

expansion module and an accessory space or return air relative

humidity sensor.

If a humidifier using a proportional steam valve is selected,

the Carrier LEN actuator (Carrier Part No. HF23BJ049) must

be adapted to the humidifier manufacturer’s steam valve. Con-

tact Belimo Aircontrols for information on actuator linkage

adapter packages required to mount the LEN actuator on the

specific brand and type of steam valve mounted by the humidi-

fier manufacturer.

The LEN actuator address must be programmed into the

ComfortLink unit’s humidifier actuator serial number variables.
NOTE: If the unit has the IGV option installed, it will be nec-

essary to fabricate a LEN harness extension to connect the

humidifier LEN actuator to the unit’s LEN harness.
SETTING UP THE SYSTEM — These humidity configura-

tion are located in the local displays under Configuration

HUMD. See Table 60. Related points are shown in Table 61.
Humidifier Control Configuration (HM.CF) — The humidi-

fier control can be set to the following configurations:
HM.CF = 0 — No humidity control.

HM.CF = 1 — Discrete control based on space relative

humidity.

HM.CF = 2 — Discrete control based on return air rela-

tive humidity.

HM.CF = 3 — Analog control based on space relative

humidity.

HM.CF = 4 — Analog control based on return air rela-

tive humidity.

Humidity Control Set Point (HM.SP) — The humidity con-

trol set point has a range of 0 to 100%.
Humidifier PID Run Rate (HM.TM) — This is the PID run

time rate.
Humidifier Proportional Gain (HM.P) — This configuration

is the PID Proportional Gain.
Humidifier Integral Gain (HM.I) — This configuration is the

PID Integral Gain.
Humidifier Derivative Gain (HM.D) — This configuration is

the PID Derivative Gain.

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