Operation - York D1SV300 Installation Instructions Manual

530.25-N2
ECONOMIZER RAIN HOOD OPTION
CAUTION. Never ouerate the unit without installingthe
ho(xl o; moisture will be drawn into tht; unit.
The outdoor and return air dampers, the sprirtg-returndam-
per actuator, the linkage, the enthalpy changeover control.
the mixed air temperature control and the minlmurn posit]on
potentiometer with manual auto switch are factory mounted
as part of the economizer option. The rain hood is shipped
in a separate package and must be assembled to the unit per
the assembly instructions in Form 530.25-N1.4.
CAUTION: Never operate the unit without installingthe
hood or moisture will be drawn into rhe unit.
FIXED OUTDOOR AIR RAIN HOOD
The fixed outdoor a]r damper with a manual adjustment arm
is factory mounted on all units without the economizer op-
tion. The rain hood is shipped in a separate package and must
be assembled to the unit per the assembly instructions in
Form 530.25-N1.3.
CAUTION: Never operate the umt without installing the
hood or moisture will be drawn into the unit.
EXHAUST AIR RAIN HOOD OPTION
The barometr~cexhaust dam~rs, the powered propeller ex-
haust fan and the damper motor end switch are factory in-
stalled and wired as part of the exhaust air option. The rain
hood is shipped in a separate package and must be assembled
to the unit per the assembly instructions in Form 530.25-N1.2
NOTE: The exhaust hood for the DSV 480 is shipped in two
pzckages.
STATIC PRESSURE REGULATOR ACCESSORY -
The Static Pressure Regulator must be field installed. Selec-
tion of best location and setpomt are the responsibility y of
the system designer. Refer to Figure 560.20-N2.2 for instal-
lation Instructions.
OPERATION OF STATIC PRESSURE CONTROL
When static pressure exceeds the static pressure setting. the
control completes an electrical circuit to the damper motor.
The motor changes the dampers to a position that reduces
the static. Whenthe static reduces to the setpoint of the con-
trol, the electrical circuit is broken, stopping the motor In
this new position, A second contact drives the motor In the
oppos]te direction on a decrease in static.
x
H
NO
AIR F LOW
?'
STATIC ~D.
A
-
DUCT ~
1
HEAD
TO
m 4
0-
POWER ~ -Q
a
o
6
REFERENCE
DAMPER MOTOR STATIC
PRESSURE
PRESSURE
CONTROL
OPERATION
D.SV VARIABLE AIR VOLUME
The operation of the D-SV unit can be divided into five
systems.
1,
2.
3.
4.
5.
Economizer System (optional).
Heating System (optional – used for night setback and
morning warmup only).
Cooling System.
Exhaust Air (optional).
Variable Air Volume Dampers (optional).
GENERAL
Variable air volume (VAV) systems operate on the principle
that space temperature can be maintained by varying the
volume of constant temperature air delivered to the space.
As the space load decreases, air delivered to the space 1spinch-
12
ed off. The optional variable air volume dampers will then
close to hold a constant duct static pressure. With less air re-
quired, both the fan and compressor requ]re less horsepower,
and operating costs are reduced.
The D-SV is a cooling only unit. Electric heat can be added
for use during night setback or morning warmup only. Dur-
ing normal operatmrr the heat is locked out.
The D SV control ISa microprocessor based Honeywell
W7100 dischargeair controller with a discharge air sense].
The control tries to maintain a fixed discharge an tempera-
ture by modu]atmg the economizer and sequencing stages
of mechanical cooling. The d!schargeair setting ISflelclad-
justable but is set at 55°F by the factory, The control JIS{J
has an adjustable cent ml band. The control band ~djustnwnt
sets a region of ternperat ure centered around the dlschargc
alr set point,
The control energizes or de-energizescoollng stage~Jnd (Jp- —
tional economizer to maintain the discharge air (D/A) temp-
erature in the control band.
Central Enwronmental Systems