Carrier 38QRR- User Manual

1

53DS --- 900 --- --- --- 060 (R --- 22)
53DS --- 900 --- --- --- 086 (Puron)

Installation Instructions

Duct---Free Systems

Cooling Only and Heat Pump Units

Low Ambient Temperature Controller Accessory

2 To 5 Nominal Tons

NOTE

: Read and become familiar with these instructions before

beginning installation.

SAFETY CONSIDERATIONS

Installing and servicing air--conditioning equipment can be
hazardous due to system pressures and electrical components.

Only trained and qualified personnel should install or service

air--conditioning equipment. When working on air--conditioning
equipment, observe the precautions provided in literature, tags,

and labels attached to the unit.
Follow all safety codes. Wear safety glasses, protective clothing,

and work gloves. Use quenching cloth for brazing operations.
Have fire extinguisher available. Read these instructions

thoroughly and follow all warnings or cautions included in

literature and attached to the unit. Consult local building codes
and National Electrical Code (NEC) for special requirements.

Recognize safety information. This is the safety--alert symbol

!

!

.

When you see this symbol on the unit and in instructions or
manuals, be alert to the potential for personal injury.
Understand these signal words: DANGER, WARNING, and
CAUTION. These words are used with the safety--alert symbol.

DANGER identifies the most serious hazards which

will

result in

severe personal injury or death.

WARNING signifies hazards

which

could

result in personal injury or death. CAUTION is used

to identify unsafe practices which

may

result in minor personal

injury or product and property damage. NOTE is used to

highlight suggestions which

will

result in enhanced installation,

reliability, or operation.

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury

or death.
Before beginning any modification or installation of this kit,

be sure the main electrical disconnect is in the OFF position.

Ensure power is disconnected to the fan coil unit. On some

systems both the fan coil and the outdoor unit may be on the

same disconnect. Tag the disconnect switch with a suitable

warning label. There may be more than one disconnect.

!

WARNING

GENERAL

IMPORTANT

: Heat pump models require an isolation relay to

prevent fan cycling in heat pump mode. See Table 1 for isolation
relay part numbers.

Table 1—Isolation Relay Part Numbers

R --- 22

Part No.

RCD

Part No.

Voltage

38BNQ009/012

HN61KK912

P283 --- 0294

120v

38BCQ018/024

HN61KK912

P283 --- 0294

120v

38BNQ018/036

HN61KK913

P283 --- 0295

240v

R --- 410a

Part No.

RCD

Part No.

Voltage

38QRR/QRF

HN61KK066

P283 --- 0293

24v

538B_R/538Q_R

HN61KK066

P283 --- 0293

24v

Wind baffles

are required for all R410a units (18--60k are blow

through design) used for low ambient operation. Use factory

accessory listed in Table 2.
Wind baffles are not available from the factory for R--22

condensers (draw through design). If wind baffles are required,
they need to be field fabricated. Baffles should be located 6”

from unit on coil side of condenser (2 sides). Use CAUTION, do

not drill into coil

Table 2—Wind Baffle Accessories for R--410A Units

R --- 410a Models

Wind Baffle Part No.

38HDF/QRF/HDR/QRR018

538E_F/538Q_F018

53DS --- 900 --- --- --- 070

38HDF/HDR024,

38HDF030,

38QRF/QRR024

538E_F/538A_R024

538E_F030, 538Q_F/538B_R024

53DS --- 900 --- --- --- 087

38HDF036, 38QRF030/035/036,

38HDR/QRR030/036 538E_F036

538Q_F030/035/036,

538A_R/538B_R030/036

53DS --- 900 --- --- --- 071

38HDR/QRR048, 060

538A_R/538B_R048, 060

53DS --- 900 --- --- --- 088

Winter Start Control

(part number KAAWS0101AAA) is

required when low ambient operation (cooling below 55

_

F) is

required for cooling and heat pump models (018--060) that have a
low pressure switch.
The Winter Start Control kit uses a time--delay relay to bypass the
low--pressure switch for three (3) minutes on start--up. the time

delay relay will take the low pressure switch out of the control

circuit to allow the system to build pressure eliminating nuisance
trips.

Units with low pressure switches: 38HDR/HDF/QRR/QRF

and 538A_B/E_F, 538Q_F.