24
only provided as an additional troubleshooting tool. The valves
will automatically go through the calibration process anytime
the unit is powered down, unit power is cycled, or anytime
there is a loss of communication between the EXV (electronic
expansion valve) board and the valve. There should be no need
to manually calibrate the valves under normal circumstances.
This sub-menu also allows manual manipulation of RHV
(reheat 3-way valve), the bypass valve, and condenser valve.
With the compressors and outdoor fans off, the user should hear
a light ratcheting sound during movement of the two modulat-
ing valves. The sound can serve as proof of valve operation.
Service Test
HMZR
RHV
(Humidi-MiZer 3-Way
Valve) — On Humidi-MiZer equipped units, this item allows
the user to switch the reheat valve from ON to OFF or OFF to
ON when compressors are in the OFF position. When RHV is
switched to the ON position, the three-way valve will be ener-
gized.
When RHV is switched to the OFF position, the three-way
valve will be de-energized. To exercise this valve with a Circuit
B compressor commanded ON, go to (
Service Test
COOL
RHV
). To view the actual valve position at any time,
the user can use the Outputs menu (
Outputs
COOL
RHV
).
Service Test
HMZR
C.EXV
(HMV-1: Condenser EXV
Position) — On Humidi-MiZer equipped units, this item
allows the user to exercise the valve that controls flow to the
Circuit B condenser. The valve default position is 100% (com-
pletely open). The user will be able to adjust the valve from 0
to 100% through this function. As confirmation that the valve
is operational, the user should hear a light ratcheting sound as
the valve opens and closes. Note that this function is only oper-
ational when Circuit B compressors are OFF. To exercise this
valve with a Circuit B compressor commanded ON, go to
(
Service Test
COOL
C.EXV
). To view the actual valve
position at any time, the user can use the Outputs menu (
Out-
puts
COOL
C.EXV
).
Service Test
HMZR
B.EXV
(HMV-2: Bypass EXV
Position) — On Humidi-MiZer equipped units, this item
allows the user to exercise the valve that controls discharge gas
bypass around the Circuit B condenser. The valve default posi-
tion is 0% (completely closed). The user will be able to adjust
the valve from 0 to 100% through this function. As confirma-
tion that the valve is operational, the user should hear a light
ratcheting sound as the valve opens and closes. Note that this
function is only operational when Circuit B compressors are
OFF. To exercise this valve when a Circuit B compressor is
ON, go to (
Service Test
COOL
B.EXV
). To view the
actual valve position at any time, the user can use the Outputs
menu (
Outputs
COOL
B.EXV
).
Service Test
HMZR
C.CAL
(Condenser EXV Cali-
brate) — On Humidi-Mizer configured units, this item
allows the user to calibrate the valve that controls flow to the
Circuit B condenser. Switching
C.CAL
to ON will instruct the
unit software to over-drive the valve in the closing direction.
This is to ensure that the valve is completely shut and to estab-
lish the “zero” open position. The controller then keeps track
of the valve's position for normal operation. During this cali-
bration phase, a light ratcheting sound may be heard and will
serve as proof of valve operation and closure.
NOTE: The calibration feature in Service Test is only provided
as an additional troubleshooting tool. The valves will automati-
cally go through the calibration process anytime the unit is
powered down, unit power is cycled, or anytime there is a loss
of communication between the EXV board and the valve.
There should be no need to manually calibrate the valves under
normal circumstances.
Service Test
HMZR
B.CAL
(Bypass EXV Cali-
brate) — On Humidi-Mizer configured units, this item
allows the user to calibrate the valve that controls discharge
gas bypass around the Circuit B condenser. Switching
B.CAL
to ON will instruct the unit software to over-drive the valve in
the closing direction.
This is to assure that the valve is completely shut and to es-
tablish the “zero” open position. The controller then keeps
track of the valve's position for normal operation. During this
calibration phase, a light ratcheting sound may be heard and
will serve as proof of valve operation and closure.
NOTE: The calibration feature in Service Test is only provided
as an additional troubleshooting tool. The valves will automati-
cally go through the calibration process anytime the unit is
powered down, unit power is cycled, or anytime there is a loss
of communication between the EXV board and the valve.
There should be no need to manually calibrate the valves under
normal circumstances
Cooling — The cooling sub-menu offers many different ser-
vice tests.
•
Service Test
COOL
RHV
(Humidi-MiZer 3-Way
Valve). On Humidi-MiZer equipped units, this item allows
the user to switch the reheat valve from ON to OFF and vice
versa. When RHV is switched to the ON position, a three-
way valve will be energized allowing refrigerant flow to
enter the reheat coil as if in a dehumidification mode or
reheat mode. When RHV is switched to the OFF position,
the three-way valve will be deenergized and the unit will
revert back to normal cooling. Note that this function only
allows manipulation of RHV if a compressor on Circuit B
has already been turned ON. To manually exercise this
valve without an active Circuit B compressor, see the sec-
tion titled
Service Test
HMZR
RHV
. To view the actual
valve position at any time, the user can use the Outputs
menu (
Outputs
COOL
RHV
).
•
Service Test
COOL
C.EXV
(HMV-1: Condenser EXV
Position). On Humidi-MiZer equipped units, this item
allows the user to exercise the valve that controls refrigerant
flow to the Circuit B condenser. To exercise the valve, RHV
must first be switched to ON (
Service Test
COOL
RHV
) and a Circuit B compressor must be com-
manded ON. The valve default position is 100% (com-
pletely open). The user will be able to adjust the valve from
0 to 100% through this function. The only constraint on the
valve position is that the percentage sum of the bypass valve
(
Service Test
COOL
B.EXV
) and condenser valve must
equal 100%. For example, if the condenser modulating
valve is only 80% open, then the gas bypass modulating
valve must remain at least 20% open. The effect of closing
the condenser valve will be to increase the supply air tem-
perature (additional reheat capacity). To view the actual
valve position at any time, the user can use the Outputs
menu (
Outputs
COOL
C.EXV
).
•
Service Test
COOL
B.EXV
(HMV-2: Bypass EXV
Position). On Humidi-MiZer equipped units, this item
allows the user to exercise the valve that controls discharge
gas bypass around the Circuit B condenser. To exercise the
valve, RHV must first be switched to ON (
Service
Test
COOL
RHV
) and a Circuit B compressor must be
commanded ON. The valve default position is 0% (com-
pletely closed). The user will be able to adjust the valve
from 0 to 100% through this function. The only constraint
on the valve position is that the percentage sum of the
bypass valve and condenser valve (
Service Test
COOL
C.EXV
) must equal 100%. For example, if the
condenser modulating valve is only 80% open, then the gas
bypass modulating valve must remain at least 20% open.
The effect of opening the bypass valve will be to increase
the supply air temperature (additional reheat capacity). To
view the actual valve position at any time, the user can use
the Outputs menu (
Outputs
COOL
B.EXV
).
Содержание Carrier Weathermaker 48A2
Страница 105: ...105 Fig 20 Typical Main Control Box Wiring Schematic 48 50A2 A3 A4 A5 Units...
Страница 106: ...106 Fig 21 Typical Auxiliary Control Box Wiring Schematic...
Страница 107: ...107 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown a48 8357...
Страница 108: ...108 TO NEXT PAGE Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown A48 7296...
Страница 109: ...109 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont A48 8358...
Страница 110: ...110 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown a50 8228...
Страница 111: ...111 Fig 25 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown...
Страница 112: ...112 Fig 26 Typical Low Ambient Controls Option Wiring...
Страница 113: ...113 Fig 27 Typical Small Chassis Component Location Size 020 035 Units...
Страница 114: ...114 Fig 28 Typical Large Chassis Component Locations Size 040 060 Units...
Страница 118: ...118 Fig 30 Economizer Control Board ECB1 and VAV Control Board ECB2 A48 7706...
Страница 142: ...142 A48 3733 Fig 56 Main Burner Removal...
Страница 176: ...176 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716...
