User Manual
13 15 1814 1716
19 21 2420 2322
indoor air. The refrigerant stays at the
same temperature and pressure until
all the refrigerant evaporates into a
gas. After the refrigerant becomes a
gas, it will continue to absorb heat
and become superheated at which
point its temperature will change. The
Superheat measurement is the best
indication of refrigerant charge level
in a fixed restrictor system. A TXV/
EXV system will keep the superheat
constant. There must be superheat
present to ensure liquid does not
ood the compressor.
Superheat measurements are
taken on the suction line between
the evaporator and compressor.
The compressor takes this low tem-
perature, low pressure, slightly super-
heated refrigerant and compresses it
to a much higher temperature and
pressure.
The highly superheated gas enters
the condenser and rejects heat into
the outside air. The refrigerant con-
denses back into a liquid. Once all
of the gas is condensed into a liquid,
Vacuum Tips
Follow all manufacturer's evacu-
ation procedures over those in this
manual in regards to specications on
how to evacuate systems. To achieve
a deep vacuum eciently Fieldpiece
recommends the following practices.
1. Remove Schrader valves from the system service
ports using a valve core removal tool (purchased
separately).
2. Use the shortest vacuum rated hoses with the
largest diameter available.
3. Inspect rubber seals at both ends of your hoses for
damage that may result in leakage.
4. Avoid using hoses with low loss ttings when
evacuating a system.
5. Avoid over-tightening the female are tting of
the SVG3. Over-tightening may cause the rubber
gasket to wear more quickly and create leaks. It is
not necessary to over tighten SVG3 to the extreme
to create a good seal.
Replacement Parts
The rubber gasket and Schrader
valve depressor are user-replaceable.
Worn out rubber gaskets can cause
leaks due to a bad seal. Over-tight-
ening of the SVG3 female are tting
may cause the rubber gasket to wear
more quickly or damage the fitting
itself. Replace if the rubber gasket
becomes worn. The rubber gasket
(standard 1/4" gasket used in refriger-
ant hoses) can easily be found at your
local HVACR distributor.
1. Remove both the Schrader valve depressor and
rubber gasket from the SVG3 cup. Dispose of worn
rubber gasket. A small pair of needle nose plyers
may used to pull out the valve depressor and the
gasket. Be careful not damage the Schrader valve
depressor.
2. Position the new rubber gasket into the top of the
cup. Push in with your nger until rubber gasket is
at the bottom of the cup.
3. Insert Schrader valve depressor into the rubber
gasket hole. Push Schrader depressor to the bottom
of the cup with your nger. You may use a pocket
SCRT to "screw" in the Schrader valve depressor if
needed.
A/C Basics
The Evaporator, Condenser, Restric-
tor (Throttling valve) and Compressor
are the four basic components of an air
conditioner. Following one pound of
refrigerant through the system shows
the function of each component.
Subcooled liquid refrigerant at high
pressure enters the restrictor and is
throttled to saturated refrigerant at a
lower pressure. The restrictor can be
either a fixed or TXV/EXV type. The
xed type must be charged to a target
superheat that varies with indoor and
outdoor conditions. TXV/EXV systems
must be charged to subcooling.
The evaporator capacity varies with
the indoor heat load on a xed restric-
tor. The TXV/EXV regulates the size of
the restriction to maintain a constant
superheat. This essentially adjusts the
capacity of the evaporator responding
to the indoor heat load.
After the restrictor, refrigerant enters
the evaporator at a low temperature
and pressure, and boils (evaporates)
into a gas by absorbing heat from the
additional removal of heat causes
a temperature drop that is known
as subcooling. TXV/EXV systems are
charged to subcooling since super-
heat is controlled by the throttle
valve. Subcooling measurements are
taken on the liquid line between the
condenser and TXV/EXV. Finally, the
subcooled liquid enters the restrictor
and the cycle starts again.
Limited Warranty
This meter is warranted against
defects in material or workmanship
for one year from date of purchase.
Fieldpiece will replace or repair the
defective unit, at its option, subject
to verication of the defect.
This warranty does not apply to
defects resulting from abuse, ne-
glect, accident, unauthorized repair,
alteration, or unreasonable use of the
instrument.
Any implied warranties arising
from the sale of a Fieldpiece product,
including but not limited to implied
warranties of merchantability and
fitness for a particular purpose, are
limited to the above. Fieldpiece shall
not be liable for loss of use of the
instrument or other incidental or
consequential damages, expenses, or
economic loss, or for any claim of such
damage, expenses, or economic loss.
State laws vary. The above limita-
tions or exclusions may not apply to
you.
For Service
In the USA, call Fieldpiece Instru-
ments for one-price-x-all out of war-
ranty service pricing. Send check or
money order for the amount quoted.
Send the meter freight prepaid to
Fieldpiece Instruments. Send proof
of date and location of purchase for
in-warranty service. The meter will be
repaired or replaced, at the option of
Fieldpiece, and returned via least cost
transportation.
For international customers, war-
ranty for products purchased outside
of the U.S. should be handled through
local distributors.
www.fieldpiece.com
© Fieldpiece Instruments, Inc 2015; v26
More Great Tools
from Fieldpiece
Maintenance
Clean the exterior with a dry cloth.
Do not use liquid.
Battery Replacement
Power off SVG3. Unscrew battery
cover, and replace the 4 AAA batteries.
Battery Cover Screw
!
Cleaning the Sensor
1. Turn o your SVG3.
2. Remove the Schrader valve depressor and rubber
gasket. A small pair of needle nose plyers can easily
pull out the depressor and the gasket at the same
time. Be careful to not puncture or tear the gasket.
3. Fill the cavity halfway with isopropyl (rubbing)
alcohol.
4. Use your index nger to cover female are tting
and gently swirl and shake the alcohol within the
cavity for about 15 to 30 seconds.
5. Pour out the alcohol and let the vacuum sensor dry
with the are tting facing down.
6. Install rubber gasket and valve depressor using
Replacement Parts section instructions.
Note: Do not use an object such as a cotton swab to
clean the sensor. This may damage the sensor.
EVAPORATOR
CONDENSER
THROTTLE
VALVE
COMPRESSOR
REFRIGERANT
FLOW
H
i
g
h
P
r
e
s
s
u
r
e
S
i
d
e
L
o
w
P
r
e
s
s
u
r
e
S
i
d
e
RETURN AIR SUPPLY AIR
OUTDOOR AIR HOT AIR
PRESS FOR 1 SECOND
AUTO-OFF
SRS2
Wireless
Refrigerant
Scale
ZERO
SYNC
UNITS
ON/OFF
PRESS FOR
1 SECOND
Wireless Refrigerant Scale
Model SRS2C
80
80
Dual In-Duct Psychrometer
Model SDP2
Wireless 4-Port Manifold
ModelSMAN460
Infrared Refrigerant Leak Dectector
Model SRL2K7
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
T2
PEAK
MUTE
ON/OFF
ON/OFF
L/M/H
SENSITIVITY
H
M
L
PEAK
LOW-BATT
PRESS FOR
1 SECOND
SRL2
Infrared
Refrigerant
Leak Detector
BATTERY
CHECK