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Wholesaler Training Program – Part 1

THERMOSTATIC EXPANSION
VALVES (TEV’S)

Thermostatic Expansion Valves
General
Thermostatic expansion valves and solenoid valves
were Sporlan’s first products. Sporlan calls the
device a “thermostatic expansion valve” abbreviated
“TEV”. Among industry person- nel it may also be
referred to as a “Thermo Valve”, “TX Valve” or just
“expansion valve”.
The TEV product line has grown to include many
different body styles for use on many refrigerants for
many applications.


Thermostatic Expansion Valves
Its principle of operation is explained in Bulletins 10-9
and 10-10 but in the simplest of terms, it is merely a
refrigerant metering device to regulate the proper
amount of refrigerant flow into the evaporator. It
accomplishes this by sensing and regulating the
amount of superheat at the outlet of the evaporator
where the bulb is fastened to the suction line.
Superheat is a term that will be heard frequently
when discussing TEV’s. In order to become more
knowledgeable on their operation a more thorough
study of “superheat” is suggested.


The Valve Types
Basic valve types have always been identified by
letters. Unfortunately there is a limit to the number of
letters in the alphabet so as Sporlan has expanded
its line over the years it has been necessary to use
some letters a second time usually after the original
valve model has discontinued for a period of time.
For the sake of simplicity each standard cataloged
valve has certain standard specifications supplied
unless otherwise specified. Some deviations are
possible on special order but are limited and should
be avoided to eliminate delays and special handling.
The following describe the standard specifications.


Type of Connections
Flare (also called SAE):
To connect a copper line to a valve having an SAE
connection, it is only necessary to “flare” the end of
the line and connect to the valve with the correspon-
ding size of flare nut. SAE connections are usually
1/4, 3/8 or 1/2. 5/8 is rare and larger sizes are not
available.
Valve types F, G and C have flare connections as a
standard in the sizes shown in Bulletin 10-10.


Type of Connections
Solder (also called “sweat” or ODF):
The nominal size for refrigeration tubing is measured
on the outside diameter (OD). Thus a 7/8 line size is
7/8” OD. To connect this line to the inlet of an
expansion valve, a 7/8 ODF (outside diameter -
female) inlet connection will allow the tube to slide
inside the fitting where the brazing or soldering takes
place.
Because of the never-ending combination of fitting
sizes the wholesaler normally stocks only the
standard connections. If the line size does not match
the standard connection, the use of reducing bushing
and/or couplings will allow the connection to be
made.
Standard valve types EG, S, SBF, EBS, O, SQ and
EQ are furnished with ODF connections.

Type of Connections
ODF flange connections:
A TEV with ODF flange connections has bolt-on steel
flanges with a brass bushing. The line is soldered to
the ODF bushing. The flange fits over the bushing
and is bolted to the valve body.
Once the bushings are brazed to the line installation
and removal of this type valve only requires bolting or
unbolting of the flange.
Types H, M, V and W are furnished with ODF flange
connections.


Type of Connections
FPT (Female pipe thread) connections:
Type D and A valves for ammonia have FPT flange
connections. Types H, M and V valves that normally
come with ODF flange connections can be adapted
to FPT with the H valve requiring special adaptors.


Other Standard Specifications
Nominal capacity:
The nominal capacities available for every valve type
is shown in Bulletin 10-10 for each refrigerant.
Capillary tube length:
The standard length for each valve type listed can
vary from 30 inches for the type F to 10 feet for the
W, D and A valves.
Size of power element:
Each valve type is made with a particular size of
power element (example: 53, 83, 33, et cetera).
The bulb size is determined by the thermostatic
charge furnished. Information on both element and
bulb size is also shown for each valve type in Bulletin
10-10.


Other Standard Specifications
Size and type of external equalizer connection:
All standard cataloged valves with SAE (Flare) and
flange connections have 1/4 SAE equalizer fittings as
standard. Those with ODF (Solder) connections are
furnished with 1/4 ODF external equalizer fittings.
The flanged H, M, V and W valves have 1/4 SAE
equalizer fittings. The D and A valves have 1/8 FPT
equalizer fittings.


More About Refrigerants and
Thermostatic Charges
Refrigerants
The material used in most valve types are compatible
with all common refrigerants. The principle exception
is the D and A valves which are used on ammonia
only.
The code letter for the refrigerant is always found in
the valve’s designation (GV is a type G valve for “22”
and GJ is for 134A). A complete list of refrigerants
and their letter code is in Bulletin 10-10.


Like body types and refrigerants, thermostatic charges are also
identified by a letter. Generally, each charge covers an
evaporator temperature range but some other application
considerations can be involved particularly on the pressure-limit
or maximum operating pressure (MOP) charges designated by
the addition of the letter “P” and sometimes a number (example
CP100).
Many of the thermostatic charges used with the newer
refrigerants are interchangeable with the older refrigerants
being replaced. As an example, the following refrigerants use
the same thermostatic charge: R-12, R-134a, R-401A, and R-
409A. This is further illustrated here for thermostatic charges
use for commercial temperature ranges of -10°F to 50°F.
The pressure limit charges (MOP) will limit the amount a TEV
opens so that the evaporator pressure will not exceed the
“Nominal System” values shown. This can be an important
feature at pull-down or after a defrost.


Internal or external equalizer
The purpose of the external equalizer (designated by the letter
“E”) is to compensate for pressure drop through the evaporator
and/or refrigerant distributor. It is generally known if a refrigerant
distributor will be used on the evaporator. However, it is rare
that wholesaler customers will know evaporator pressure drop.
Therefore, the following rule-of-thumb is suggested:
A. Use the externally equalized valve on any evaporator
equipped with a refrigerant distributor.
B. Use the externally equalized valve when there is any doubt
and particularly on valves with nominal capacities above 1
ton. There is no disadvantage to using it even if it is not
required.
C. Use the internally equalized valve on small tonnage TEV’s
(below 1 ton) when it is known that the evaporator is single-
circuit with no refrigerant distributor.


Balanced Port Thermostatic
Expansion Valves
The port construction of standard thermostatic
expansion valves is such that the pressure drop
across it (difference between inlet and outlet) tends
to open the valve. This pressure imbalance has little
effect on the TEV’s operation under most normal
operating conditions, particularly on small valves.


Expansion Valves
On larger valves with greater port areas it becomes
more of a factor and our type V and W valves have
always been made with semi balanced ports. The
type “O” valve was later introduced which has a
completely balanced port.


Expansion Valves
The type “O” valve with its balanced port construction
has been widely accepted for its ability to maintain
close control under conditions of varying inlet
pressure and fluctuating loads. With its large capacity
ratings the O valve is ideally suited for chillers or
other applications where head pressure can fall and
loads can change.


Expansion Valves
The balanced port version of the F valve is the Type
BF, EBF and SBF. The balanced port S valve is type
EBS.
Bulletin 10-10 provides further information on the BF
valve.


Power Elements
The power elements are replaceable on most
standard TEV’s.
The power element consists of the bulb, capillary
tube, diaphragm case assembly and the thermostatic
charge it contains. Replacement power elements are
supplied in kit form with a prefix KT (for
Kit, Thermostatic) to the designation followed by a
number indicating the lock ring size, as well as the
refrigerant letter designation. The length of the cap
tube should also be specified when ordering. This
KT-83-VCP100 indicates the following:
1. KT - 83 Element size 83
2. V Refrigerant 22
3. CP100 Thermostatic charge CP100


About Changing Power Elements
The type “Q” Valve is designed to provide the
flexibility for changing power elements and nominal
capacities. For more information about the Type Q
Valve, there is a separate program available covering
its features. When other standard valves are involved
in power element changes, other considerations are
involved:


About Changing Power Elements
When changing from one thermostatic charge to
another using the same refrigerant, the nominal
capacity remains the same and the stamping on the
valve body will still reflect the correction identification.
However, the customer should be advised that a super-
heat adjustment might be required.
When changing from one refrigerant to another, the
nominal capacity will probably change. As an
example, the same port size is rated for nominal 5 tons
on R-22 and 3 tons on R-12 and R-134a. Also, it is very
likely that a superheat adjustment will be required
because of variations in the superheat spring sizes. One
other point to remember is that the identification
stamped on the valve body, showing the original
refrigerant and nominal capacity, will no longer correctly
identify the valve. The Q valve design is such that these
problems are eliminated.


Supplying the Customer with the
Correct TEV
Wholesalers are often confronted with the problem of
supplying their customers with the correct TEV based
on information that is incomplete, or inaccurate.
When this occurs, asking the right questions can
often lead to a solution. Generally, one of the
following situations is involved:


Correct TEV
Selection of a TEV for a new application
This can become a case of how precise the customer may be in
his requirements. One extreme is the engineer who supplies
every detail on the system characteristics. On the other end of
the scale is the service mechanic who may say, “give me a 5
ton valve!”
Finding the correct valve capacity
The nominal capacity rating (except for ammonia) is based on:
a. 40 degrees F evaporator temperature
b. 100 PSI pressure drop across TEV (60 PSI for R-134a)
c. 100 degrees F vapor-free liquid entering TEV.
TEV’s for air conditioning applications including water chillers
will usually fall roughly into the conditions shown above. This
means that a nominal 5 ton valve will be selected for a 5 ton or
5 horsepower system. This situation calls for an SVE-5- CP100
or SVE-5-GA.


Correct TEV
For refrigeration applications the selection can
become a little more involved, particularly when
operating conditions become more variable.
TEV capacity tables assume that the pressure
drop across it will be in accordance with the
evaporator pressure that is expected at the
particular evaporator temperature. In other
words, with a constant discharge pressure (TEV
inlet) the pressure drop increases as the
evaporator pressure (temperature) is reduced.
Therefore, for R-22 and equivalent
refrigerants, the pressure drop is assumed to be
100 psi at a 40°F evaporator, 125 psi at 0°F to
10°F evaporator, 150 psi at -10°F to -20°F, and 175
psi drop at -40°F. The entering liquid temperature
is based on 100°F at all evaporator temperatures.


Correct TEV
In the example shown, valve types NI, F, EF, G, &
EG all have rated capacities of 1.09 tons at a 20°F
evaporator and standard conditions of 125 psi
pressure drop and 100°F entering liquid
temperature.


Correct TEV
When the entering liquid temperature and/or
pressure drop across the TEV is significantly
different from stated standard
conditions, correction factors are applied to the
TEV’s rated capacity as shown in the capacity
tables.
In this example, an adjusted capacity is
calculated for the valve selected from the
capacity table based on standard conditions at a
20°F evaporator.


Correct TEV
The correction factor for 70°F liquid is found from
the table to be 1.17 and the factor for 100 psi is
shown as 0.89. The two correction factors
multiplied by each other and then times the rated
capacity of 1.09 results in new capacity of 1.13
tons and the type EGVE-1 is chosen for a one ton
load.


Correct TEV
Assuming that a refrigerant distributor is used, a TEV
with an external equalizer will be required. When
determining the pressure drop through the
evaporator, the drop across the distributor must be
included. In this typical example, the suction pressure at
the compressor is 43 psig, but the pressure at the outlet
of the TEV is only 78 psig.
Therefore, an external equalizer is required designated
by the letter “E”. Again, the purpose of the external
equalizer is to compensate for the pressure drop
through the evaporator and /or refrigerant distributor.
The final consideration is the thermostatic charge. Since
the specified evaporator temperature is 20°F, a “C”
charge is selected.
The complete designation for the selection is EGVE-1-
C, 3/8 X 1/2 ODF-5”


Correct TEV
Selecting a Replacement TEV For Another
Sporlan Valve
• Standard Cataloged Valves
A. This is a case of getting the required information from the
old valve not always an easy task!
B. Bulletin 210-60 will serve as a guide to directing the
customer to the location of the identifying numbers and
letters on the valve.

All Sporlan TEV’s have permanent identifying marks
and most have an identifying label on the power
element showing sufficient information to select a
replacement. Unfortunately this label can become
obliterated with age and it then becomes necessary
to seek out the permanent markings as shown in
Bulletin 210-60.


Correct TEV
Replacement of Special Non-Cataloged Valves
Sporlan manufactures many special TEV’s for OEM’s
- usually modifications of standard valves to meet the
particular requirements of their unit.
Identifying and selecting a replacement can often be
handled with the assistance of bulletins in the “210”
section of your wholesaler’s manual.


Correct TEV
The special designations will usually be one of the following:
• Type I or BI valve (example - IVE-2-GA, BIVE-2-GA and
BBIVE-2-GA): Sporlan type Q or RCVE valves can often be
matched to the specifications of these models. The BBI
valve having a balanced port might be replaced by a type
SBF. The above original valves will most likely be non-
adjustable. The standard replacements will have adjustable
superheat to allow for an adjustment to match any special
setting that was originally furnished to the OEM.
• Type X Valve (example - XVE-7 1/2-CP100): This valve is
usually field replaced with a standard type
S, G, C, RCVE, or Q valve.
• Valves Identified with a “Y” Number (example - Y362GR-1-
Z): These are the most difficult to identify since the “Y”
numbers that Sporlan have used over the years is now in
excess of 1,000 and each number signifies some special
feature known only to Sporlan and perhaps the OEM. This
then becomes a case of contacting Sporlan or directing the
customer to the OEM involved. Delivery is usually long.


Correct TEV
Selecting A Replacement For A Competitive TEV
This is another case where there can be no easy guide to
making a proper selection because of the wide number of
manufacturers and model numbers involved. Sporlan does
publish a cross-reference table with competitive valves.
The cross references are based on nominal capacity matches.
Valve performance, and thus system performance, cannot be
guaranteed when replacing a valve using these cross
references because of unique valve flow characteristics and
potentially differing test and rating procedures by the valve
manufacturers. There is also no assurance that the valve being
replaced has been properly sized for the systemrequirements.
Therefore it is always recommended to properly confirm the
valve selection as outlined in Bulletin 10-10.
Note: This is a nominal capacity cross reference only. Physical
attributes, such as connection sizes, body configuration, lay in
dimensions, and capillary tube length may not be identical. Due
to some of the differing valve physical attributes, some system
modifications may be required.
Most wholesalers have competitive catalogs for reference.


Correct TEV
Identification of Numbers and/or Letters Not
Commonly Encountered
Customers may occasionally provide unrecognizable
designations other than “Y” numbers or OEM
specials such as I, BI and X valves. The following are
some of these cases:
• Suffix numbers to “P” charges (example GRE-2-
ZP35): These numbers indicate a pressure limit
other than standard. Bulletin 10-10 shows the
standard pressure limit values for all standard
charges. As an example the RZP standard factory
air test settings is 45 PSI.

Therefore, an RZP35 charge has a pressure limit
setting to 10 PSI below the standard RZP.


Correct TEV
• BP and RPB: TEV’s with either of these features
are designed for use on systems having a “low
starting torque” compressor motor (such as
permanent split capacitor or PC motor). This type
of compressor will start only if there is a negligible
difference in high and low side pressures.

Both the BP and the RPB features allow the TEV
to equalize the high and low side pressures when
the compressor is stopped. When restarting there
is virtually no pressure difference and the
compressor is stopped.
• The letters BP stand for “bleed port” and will be
followed by a number to indicate the percent of
bleed. Thus BP/30 means a 30% bleed.


Correct TEV
The letters RPB stand for “rapid pressure balance”
and does not include a number as in the case of
straight bleed-port valves (BP).
Replacement of a TEV on a system with a PSC
motor (low starting torque) must have a bleed port or
RPB feature. A standard TEV without the BP or RPB
can only be used by adding a “hard-start kit” to the
compressor motor. Also 3-phase compressor motors
do not require the BP or RPB feature.
Non-adjustable TEV’s: Some standard models of
TEV’s are made non-adjustable for OEM’s. The
designation for these use the “N” prefix such as
NSVE-8 which is replaced in the field by a standard
SVE-8.


Correct TEV
Replacement Parts for TEV’s
Sporlan TEV’s are very trouble-free and service or
necessity for replacement parts is extremely rare. Most
complaints involving the operation of TEV’s can usually
be traced to contaminants in the refrigerant. It is a well
established fact that because of the valve’s location in
the system, even the smallest trace of circulating
contaminants will eventually be trapped by the TEV. Of
course the Sporlan Catch-All is the best insurance
against this happening and will be discussed later.
Wear to any of the TEV parts is practically nonexistent
which leaves only the loss of the thermostatic charge as
a possible source of TEV failure. Replacement power
element kits are available for this purpose.
In general, even though replacement internal parts kits
are available for some valves, repairing of TEV’s is
considered impractical because of the cost of labor
compared to the cost of a new valve.



REFRIGERANT
DISTRIBUTORS

Refrigerant Distributors
General
The refrigerant distributor is a device not often sold
by a wholesaler since it is usually included with the
evaporator coil by the OEM. Nevertheless, the
wholesaler is frequently called on to supply parts to
modify it to accommodate some design change such
as a change in refrigerants, capacity or addition of
hot gas defrost or hot gas bypass.


Basic Distributor Construction
Standard refrigerant distributors consist of 3 parts:
A. Body (designated by 4 digit number, i.e.: 1113)
B. Nozzle (designated by a letter and a number, i.e.:
G-6)
C. Retainer Ring (designated by same letter as
nozzle)


Bulletin 20-10 is the guide to finding:
A. Number and size of circuits available for each
distributor body.
B. Nozzle type (L, J, G, E, C, or A) that fit a particular
distributor model.
C. Nozzle orifice size and corresponding capacity for
each (numbered 1/9 to 50).


Refrigerant distributors for hot gas defrost, heat
pump, or reverse flow (distributors with auxiliary side
connectors)
A. The 1650 series (1650, 1, 2, 3, 4, 5, 6, 7, 9) are
constructed with a connection on the side to receive
hot gas for defrost purposes or to collect liquid from
the evaporator on reverse flow such as a heat pump.
B. Models 1651, 3, 5, 7 and 9 use standard nozzles
J, G, E, C, and A respectively. Models 1650, 2, 4 and
6 have nozzles that cannot be removed.
C. The purpose for using all the above models instead
of a “Tee” between the TEV and distributor is to
allow the hot gas or reverse flow to pass through the
distributor without going through the restriction of the
nozzle.

Refrigerant distributors for hot gas bypass:
A. Refrigerant distributors for hot gas bypass
applications have the same basic construction
except for the internal machining of the
distributor body and the use of a “extended tube”
nozzle. Both are designated by the letter “R”
added to the number of the distributor and/or
nozzle. Example: 1653R for the distributor and
GR for the nozzle.


Refrigerant distributors for hot gas bypass:
B. The “R” models use special distributor body
machining and special nozzles to permit the
mixing of the hot gas from the bypass valve and
the refrigerant feed from the TEV. This is
accomplished without upsetting the proper
refrigerant distribution into each circuit of the
distributor.
C. “R” models can be used on both hot gas bypass
and hot gas defrost and reverse flow systems.
However, the standard 1650 series (without “R”)
should not be used on hot gas bypass systems.


Converting standard distributors to side outlet
models:
Customers will occasionally want to add hot gas
bypass or hot gas defrost to an evaporator that was
originally furnished with a standard distributor.
This can be accomplished with the use of an auxiliary
side connector (ASC).
A. ASC models that fit standard model distributors
are listed in bulletin 20-10.
B. Customers should follow the instructions for
locating the ASC and relocating the nozzle from
the distributor to the ASC.


C. The ASC adapter provides a second option for
supplying a customer with a distributor with an
auxiliary side connection. In this example, a
1651R-3-1/4-4 with a 1/2 OD side connection
serves the same purpose as a 1620-3-1/4 in
combination with an ASC-5-4 using a J-4 nozzle.



LEVEL-MASTER CONTROL


Sporlan Level-Master Control
The Sporlan Level Master control is a modified TEV
designed for application to flooded systems only. The
basic difference between the Level-Master and a
TEV is in the construction of the power element. This
LMC element has an insert type bulb and contains a
small heating element. The complete power element
including the heater is available as a separate part.
The heater only is also available as a replacement
part.
The Level-Master has limited application because of
the relatively small number of flooded refrigeration
systems in existence or being built. Most flooded
systems use ammonia and are usually found in
industrial applications.
Bulletin 60-15 gives details of construction, operation
and application.


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