79
Fig. 86 — Manual Air Vent
Fig. 87 — Automatic Air Vent
Direct Expansion (DX) Systems
NOTE: Operation of DX equipped fan coils at any fan speed other
than high fan speed is not approved and will void the manufactur-
er's limited warranty.
Air System Balancing
All ductwork must be complete and connected. All grilles, fil-
ters, and access doors and panels must be properly installed to
establish actual system operating conditions BEFORE beginning
air balancing operations.
Each individual unit and the attached ductwork is a unique sys-
tem with its own operating characteristics. For this reason, air
balancing is normally done by balance specialists who are famil-
iar with all procedures required to properly establish air distribu-
tion and fan-system operating conditions. These procedures
should not be attempted by unqualified personnel.
Exposed units without ductwork do not require air balancing
other than selecting the desired fan speed.
After proper system operation is established, the actual unit air
delivery and the actual fan motor amperage draw for each unit
should be recorded in a convenient place for future reference.
Refer to Tables 8-11.
Maximum External Static Pressures
Water System Balancing
A complete knowledge of the hydronic system, along with its
components and controls, is essential to proper water system bal
-
ancing. This procedure should not be attempted by unqualified
personnel. The system must be complete, and all components
must be in operating condition BEFORE beginning water system
balancing operations.
Each hydronic system has different operating characteristics de-
pending on the devices and controls used in the system. The actual
balancing technique may vary from one system to another.
After the proper system operation is established, the appropriate
system operating conditions such as various water temperatures
and flow rates should be recorded in a convenient place for future
reference.
Before, and during water system balancing, conditions may exist
due to incorrect system pressures which may result in noticeable
water noise or undesired valve operation. After the entire system is
balanced, these conditions will not exist on properly designed
systems.
Water Treatment
Proper water treatment is a specialized industry. Carrier recom-
mends consulting an expert in this field to analyze the water for
compliance with the water quality parameters listed below, and to
specify the appropriate water treatment regimen. The expert may
recommend typical additives such as rust inhibitors, scaling pre
-
ventative, antimicrobial growth agents, or algae preventatives.
Anti-freeze solutions may also be used to lower the freezing point.
Carrier water coil tubes and headers are constructed of pure
copper. Multiple brass alloys may be present in the valve package,
depending on unit configuration. It is the user's responsibility to
ensure the tube and piping materials furnished by Carrier, are
compatible with the treated water.
Refer to Table 12.
IMPORTANT: Do not operate fan coils with a DX evaporator
coil plus contiguous hydronic coil without use of a suitable
glycol solution that is approved for use by the manufacturer.
Failure to follow this instruction will void the manufacturer's
limited warranty.
IMPORTANT: Should the evaporator freeze due to inadequate
airflow for any reason, damage may occur to adjacent water or
steam coil tubing. This type of issue is due to product misappli-
cation and voids the manufacturer's limited warranty
Table 8 — 42D* Hi-Performance
External Static Pressure
Max at High Speed 0.70
Max at Medium Speed 0.61
Max at Low Speed 0.50
Table 9 — 42C* Horizontal Ceiling
External Static Pressure
Max at High Speed 0.50
Max at Medium Speed 0.40
Max at Low Speed 0.20
Table 10 — 42V*D Vertical Floor
External Static Pressure
Max at High Speed 0.40
Max at Medium Speed 0.29
Max at Low Speed 0.12
Manual Air Vent
Table 11 — 42V*A Vertical Floor Lowboy
External Static Pressure
Max at High Speed 0.50
Max at Medium Speed 0.42
Max at Low Speed 0.25
IMPORTANT: Failure to provide proper water quality will void
the fan coil unit's warranty.
Table 12 — Water Quality Concentrations
a,b
a. Maximum Water Operating Temperature: 190°F (87°C).
b. Maximum Allowable Water Pressure: 500 psig (3447 kpa).
WATER CONTAINING REQUIRED CONCENTRATION
Sulphate Less than 200 ppm
pH 7.0 to 8.5
Chlorides Less than 200 ppm
Nitrate Less than 100 ppm
Iron Less than 4.5 mg/l
Ammonia Less than 2.0 mg/l
Manganese Less than 0.1 mg/l
Dissolved Solids Less than 1000 mg/l
CaCO3 Hardness 300 to 500 ppm
CaCO3 Alkalinity 300 to 500 ppm
Particulate Quantity Less than 10 ppm
Particulate Size 800 micron max
To Next Page
Loading...
