Quantech QWC4, Installation Operation & Maintenance, Page: 21 / 156

QUANTECH
21
SECTION 2 - PRODUCT DESCRIPTION
FORM QWC4-NM1 (221)
ISSUE DATE: 02/28/2021
2
Double Thick Insulation 1 1/2 in. (38 mm) insulation
is available on the evaporator as a factory-installed op-
tion.
Controls Options
BAS Temperature Reset is a factory-installed option
to accept a 4 mA to 20 mA or a 0 VDC to 10 VDC
input. This option allows remote reset of the Leaving
Chilled Liquid Temperature Setpoint (LCHLTS). The
setpoint can be positively offset up to 40°F (22.2°C).
This option is useful for ice storage or process applica-
tions, or for periods where higher chilled liquid tem-
peratures are adequate for low loads, which is available
alone or in combination with the BAS load limit.
BAS Load Limit is a factory-installed option that ac-
cepts a 4 mA to 20 mA or a 0 VDC to 10 VDC in-
put. This option allows remote reset of the load limit
setpoint, which can limit system demand from 30%
to 100%, which is available alone, or in combination,
with the BAS temperature reset.
E-Link Gateway option provides communication or
BAS, including BACnet (MS/TP), Modbus, LON, and
N2 between the control panel and the BAS.
General Options
Flow Switch Accessory Switch
NEMA 3R switch, 150 psig (10.3 kPA) DWP, -20°F to
250°F (-29°C to 121°C) with 1 in. NPT (IPS) connec-
tion for upright mounting in horizontal pipe. This flow
switch (or equivalent) must be furnished with each
unit for chilled liquid loop. The condenser liquid flow
switch is optional.
(Field mounted)
Differential Pressure Switch
This 3 psig to 45 psig (0.2 barg to 3 barg) range switch,
with 1/4 in. NPTE pressure connections, is an alterna-
tive to the paddle-type flow switch. (Field mounted)
Dual Pressure Relief Valve
Two safety relief valves are mounted in parallel; one
valve is always operational to assist in valve replace-
ment during maintenance.
Electrical Isolation
Circuit Breaker (UL/ASME) – A unit-mounted cir-
cuit breaker with external lockable handle will be
supplied to isolate the single point power voltage for
servicing. Circuit breaker is sized to provide motor
branch, short circuit and ground fault protection for the
motor branch-circuit conductors and control apparatus,
and the motors.
Non-Fused Disconnect Switch (CE/PED) – Unit-
mounted disconnect switch with external lockable han-
dle can be supplied to isolate the unit power voltage for
servicing. Separate external fusing must be supplied by
the power wiring, which must comply with local codes.
Optional Special Requirement Documents
Special Requirement Document Package (SRDP) may
include:
• Pressure vessel report
•
Production system and final unit inspection check
sheets
• Steel mill material reports for vessels
•
CE certificate
• Unit run test report
• Final unit/component inspection
• Hydro, vacuum, and pneumatic tests
• Electrical safety
Vibration Isolation
Elastomeric Isolators – Use for normal installations.
(Field mounted)
Spring Isolators (1 in (25.4 mm))
– To support the
unit, spring isolators are level adjustable spring and
cage isolators for mounting under the unit base rails.
The nominal deflection may vary slightly by applica-
tion. (Field mounted)
Refrigerant Isolation Valves
Optional, factory-installed isolation valves in the com-
pressor discharge lines and refrigerant liquid line per
circuit are available. The valves allow isolation and
storage of the refrigerant charge in the chiller condens-
er during servicing, which eliminate time-consuming
transfers to remote storage vessels. Both valves in each
independent refrigerant circuit are positive shut-off, as-
suring integrity of the storage system.