www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com www.fieldpiece.com
2 2
2 3
2.1
Superheat Overview
Superheat is the temperature rise above the boiling point of the refriger-
ant. Too high, and the refrigerant boils off early in the evaporator and wastes
most of the capacity of the evaporator. Too low, and you risk liquid going into
the compressor.
Using superheat is the best way to obtain proper refrigerant charge for a
fixed restrictor metering device system.
If the air conditioner is in good working order and the airflow is adjusted
properly, comparing the actual and target superheat will tell you if refriger-
ant needs to be added or recovered. Ensure the pressure never exceeds the
manufacturer's maximum overload pressure guidelines.
On a fixed restrictor system, the target superheat is determined based
upon the indoor wet bulb and outdoor dry bulb temperatures.
The Actual SH (superheat) should be within ±5°F of the Target SH to
ensure optimum performance. If the actual SH is outside this range, modi-
fications to the charge or adjustments to the restrictor (TXV) are necessary.
Adding refrigerant lowers Actual SH. Recovering refrigerant increases
your Actual SH. The amount of refrigerant necessary to add or recover will
vary based on the size of the system and the difference between the Actual
and Target SH.
To get Actual Superheat, you need to measure suction line pressure and
suction line temperature. To get Target Superheat heat for fixed restrictor sys-
tems you need to measure return air wet bulb and outdoor dry bulb.
Because everything within the system is interdependent, one adjustment
can affect other parts of the system. For example, increasing airflow increases
the superheat, which may require adding refrigerant. After modifications, al-
low 15 minutes to stabilize and then retest.
Refrigeration Cycle
Use the HG3, ASX14 and ATC1
to get actual superheat.
EVAPORATOR
CONDENSER
THROTTLE
VALVE
COMPRESSOR
REFRIGERANT
FLOW
H
ig
h P
ress
ure Side
Low Press
ure
Sid
e
RETURN AIR
SUPPLY AIR
OUTDOOR AIR
HOT AIR
AA
V3
Air V
elocity
& T
emper
atur
e
Accessor
y
Head
ON
LCD
X100
LO BA
TT
READ
ENGLISH
ENGLISH
METRIC
Ft/min
MPH
°F
M/s
KM/hr
°C
METRIC
AV
G
NORMAL
ATH4
AUT
O OFF
ARH4
T1-T2
T2
T1
Function
T1
CAL
T2
CAL
AUT
O OFF
°C
°F
T1
T2
Set meter to mVDC
range to display
temperature directly
.
LO BA
TT
ON
Dual
Temper
atur
e
Head
OFF
ATH4
T1-T2
T2
T1
Function
T1
CAL
T2
CAL
AUT
O OFF
°C
Set meter to mVDC
range to display
temperature directly
.
LO
BA
TT
ON
Dual
Temper
atur
e
Head
OFF
ASX14
ACH4
Sync
ET2W
Air
Conditioner
Superhea
t and
Subcooling
AUT
O
OFF
T/C
CAL
ATH4
T1-T2
T2
T1
Function
T1
CAL
T2
CAL
AUT
O OFF
°C
°F
T1
T2
Set meter to mVDC
range to display
temperature directly
.
LO BA
TT
ON
Dual
Temper
atur
e
Head
OFF
SET
AT
M
ST
ABLE
ON
LO BA
TT
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sling
Psy
chr
ometer
Head
ON
AUT
O OFF
1%RH/mVDC
1°F/mVDC
1°C/mVDC
LO BA
TT
DEW POINT
%RH
WET B
ULB
TEMP
°F
°C
ON
OFF
ACM3
AOX
2
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Sync
ET2W
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEAD!
LO BA
TT
SEND
RECEIVE
ON
AC
DC
W
ireless
Transmitter
Carbon
Mono
xide
Accessor
y
Head
ON
Converts
1PPM CO
concentration
to 1mVDC
LO BA
TT
ON
OF
F
AVERA
GE
NORM
AL
AUT
O
OFF
ZERO
SET
CA
T.III
300V
400A
CLAM
P
AC Cur
rent
Clamp
1AAC / 1mV
AC
400AAC MAX
!
Combustion
Chec
k
%O
%CO
TEMP
ON
GAS
OIL
Lo Batt
°C °F
AUT
O
OFF
ST
ABLE
Fuel T
ype
2
2
T/C
CAL
ARH4
Sling
Psy
chr
ometer
Head
ON
AUT
O OFF
1%RH/mVDC
1°F/mVDC
1°C/mVDC
LO BA
TT
DEW POINT
%RH
WET B
ULB
TEMP
°F
°C
ON
OFF
ATH4
T1-T2
T2
T1
Function
T1
CAL
T2
CAL
AUT
O OFF
°C
°F
T1
T2
Set meter to mVDC
range to display
temperature directly
.
LO BA
TT
ON
Dual
Temper
atur
e
Head
OFF
AA
V3
Air V
elocity
& T
emper
atur
e
Accessor
y
Head
ON
LCD
X100
LO BA
TT
READ
ENGLISH
ENGLISH
METRIC
Ft/min
MPH
°F
M/s
KM/hr
°C
METRIC
AV
G
NORMAL
AUT
O OFF
AOX
2
Combustion
Chec
k
%O
%CO
TEMP
ON
GAS
OIL
Lo Batt
°C °F
AUT
O
OFF
ST
ABLE
Fuel T
ype
2
2
T/C
CAL
ACM3
Carbon
Mono
xide
Accessor
y
Head
ON
Converts
1PPM CO
concentration
to 1mVDC
LO BA
TT
ON
OFF
AVERA
GE
NORM
AL
AUT
O
OFF
ZERO
SET
ACH4
CA
T.III
300V
400A
CLAM
P
AC Cur
rent
Clamp
1AAC / 1mV
AC
400AAC MAX
!
ASX14
Air
Conditioner
Superhea
t and
Subcooling
AUT
O
OFF
T/C
CAL
SET
AT
M
ST
ABLE
ON
LO BA
TT
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Jacket
Charging
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Light
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Service
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Light
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Service
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Clear
Input
Output
Sync
Recall
Enter
Save
MAX 30VDC
24VAC
CONNECT ONLY TO
ACCESSORY HEADS!
HVAC Guide
Fieldpiece HG3
SETUP
Target
Evaporator
Logger
Exit Temp
CFM
Display
Superheat
Subcooling
Combustion
CheckMe!
Data
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
Jacket
Charging
OUTPUT FORM
CO2: 6.3%
Excess O2:
76.8%
COAF: 103ppm
Net Temp:
82 ˙F
Standard Eff:
85%
Siegert Eff:
94%
Draft Press: 0.08IWC
INPUT FORM
Pressure is between
160psig and 220psig.
SL Pressure: ---.-psig
LL Pressure: ---.-psig
Difference: ---.-psig
Confirm Pressures
CustomerID: __JONES123
INPUT FORM
SH Table:Standard
Refrigerant:R-22
OD Dry Bulb:
85.4
˙F
Return WB:
61.0˙F
SL Pressure
:
---.-˙F
SL Temp:
--.-˙F
CustomerID:__JONES123
INPUT FORM
Into Evap
Return DB
: 72.1
˙F
Return WB:
64.5˙F
Out of Evap
Supply DB:
55.6˙F
CustomerID: __JONES123
Units:English
INPUT FORM
Span: 2hours
Per: 30seconds
SEY
SET ID:IndoorTemp
Measurement: 72.8
SET ID:CompAmps
Measurement: 17.2
INPUT FORM
ACV
CustomerID
:--JONES123
01/24/2000 04:20:22PM
OUTPUT FORM
CO2: 6.3%
Excess O2:
76.8%
COAF: 103ppm
Net Temp:
82 ˙F
Standard Eff:
85%
Siegert Eff:
94%
Draft Press: 0.08IWC
INPUT FORM W/O
Manufacturer’s Data
Refrigerant: R-22
LL Pressure: 220.3psig
LL Temp
:
91.1˙F
CustomerID:__JONES123
Units:English
12/31/2011 11:59:59PM
INPUT FORM W/O
Manufacturer’s Data
Refrigerant: R-22
LL Pressure: 220.3psig
LL Temp
:
91.1˙F
CustomerID:__JONES123
Units:English
12/31/2011 11:59:59PM
INPUT FORM
Into Evap
Return DB:
72.1
˙F
Return WB:
64.5˙F
Out of Evap
Supply DB
:
55.6˙F
CustomerID: __JONES123
Units:English
INPUT FORM
Refrigerant:R-410A
Constrict the
Charging Jacket until
the difference
between the SL
Pressure and LL
Pressure is between
INPUT FORM
SH Table:Standard
Refrigerant:R-22
OD Dry Bulb:
85.4
˙F
Return WB:
61.0˙F
SL Pressure
:
---.-˙F
SL Temp:
--.-˙F
CustomerID:__JONES123
INPUT FORM
Sys Type
:AC
Grant and Sys Info:
None
INDOOR UNIT
Meter Device:TXV/TEV
Return DB:
71.7˙F
Return WB:
60.8˙F
INPUT FORM
Sys Type
:AC
Grant and Sys Info:
None
INDOOR UNIT
Meter Device:TXV/TEV
Return DB:
71.7˙F
Return WB:
60.8˙F
Memory:
Com with PC
Erase a Single Test
Erase a Customer
Erase a Grant
Check Memory Status
Clear Data logs
Clear All Data
Memory:
Com with PC
Erase a Single Test
Erase a Customer
Erase a Grant
Check Memory Status
Clear Data logs
Clear All Data
INPUT FORM
SET ID:IndoorTemp
Measurement: 72.8
SET ID:CompAmps
Measurement: 17.2
Span: 2hours
Per: 30seconds
START
INPUT FORM
DCV
CustomerID
:--JONES123
01/24/2000 04:20:22PM
INPUT FORM
Grille 01
ID:LivingRm1
Flow:Supply
Manufacturer’s Data
Free Area in sqft:
00.421sqft
Velocity
: 212ft/min
INPUT FORM
Grille 01
ID:LivingRm1
Flow:Supply
Manufacturer’s Data
Free Area in sqft:
00.421sqft
Velocity
: 212ft/min
INPUT FORM
Into Evap
Return DB:
72.1
˙F
Return WB:
64.5˙F
Out of Evap
Supply DB:
55.6˙F
CustomerID
: __JONES123
Units:English
ARH4
Sling
Psychrometer
Head
ON
AUTO OFF
1%RH/mVDC
1°F/mVDC
1°C/mVDC
LO BATT
DEW POINT
%RH
WET BULB
TEMP
°F
°C
ON
OFF
ATH4
T1-T2
T2
T1
Function
T1
CAL
T2
CAL
AUTO OFF
°C
°F
T1
T2
Set meter to mVDC
range to display
temperature directly.
LO BATT
ON
Dual
Temperature
Head
OFF
ATH4
T1-T2
T2
T1
Function
T1
CAL
T2
CAL
AUTO OFF
°C
°F
T1
T2
Set meter to mVDC
range to display
temperature directly.
LO BATT
ON
Dual
Temperature
Head
OFF
AAV3
Air Velocity
& Temperature
Accessory
Head
ON
LCD
X100
LO BATT
READ
ENGLISH
ENGLISH METRIC
Ft/min
MPH
°F
M/s
KM/hr
°C
METRIC
AVG
NORMAL
AUTO OFF
AOX2
Combustion
Check
%
O
%
CO
TEMP
ON
GAS
OIL
Lo Batt
°C °F
AUTO
OFF
STABLE
Fuel Type
2
2
T/C
CAL
ACM3
Carbon
Monoxide
Accessory
Head
ON
Converts
1PPM CO
concentration
to 1mVDC
LO BATT
ON
OFF
AVERAGE
NORMAL
AUTO
OFF
ZERO
SET
ACH4
CAT.III
300V
400A
CLAMP
AC Current
Clamp
1AAC / 1mVAC
400AAC MAX
!
ASX14
Air
Conditioner
Superheat and
Subcooling
AUTO
OFF
T/C
CAL
SET
ATM
STABLE
ON
LO BATT
