TEC Option Codes

  • Multi-TEC matched set height tolerances down to ± 0.0003 inches.
  • Lapped (ceramic), metallized, or pre-tinned faces available.
  • TEC Sectioning to reduce stresses in extreme cycling applications.
  • Call for custom options.

Face Options

4th digit of part number, default is "1"

  • Metallized faces allow for tight height tolerances down to ±0.0003 inches. This is especially important when your application uses 2 or more TEC's in an assembly. Available on TiTan and Mini TECs only.
  • Metallized faces also allow for solder mounting which is a superior heat transfer path compared to thermal greases and epoxies. (Solder mounting is not recommended for TECs larger than 25mm)

NOTE: Not all face options are available on all products.

0 = Metallized, top and bottom faces
1 = Lapped, top and bottom faces
2 = Metallized top, lapped bottom
3 = Lapped top, metallized bottom

Wire Type

8th digit of part number, default is "L"


U = 32 AWG or less Bus wire
A = 30 AWG Bus wire
B = 28 AWG Bus wire
3 = 27 AWG Bus wire
C = 26 AWG Bus wire
Z = 24 AWG Bus wire
V = 22 AWG Bus wire
D = 20 AWG Bus wire
I = 18 AWG Bus wire
E = 16 AWG Bus wire

F = 30 AWG Bus wire w/ insulation
S = 28 AWG Bus wire w/ insulation
G = 26 AWG Bus wire w/ insulation
T = 24 AWG Bus wire w/ insulation
W = 22 AWG Bus wire w/ insulation
H = 20 AWG Bus wire w/ insulation
O = 18 AWG Bus wire w/ insulation
Y = 16 AWG Bus wire w/ insulation

J = 30 AWG stranded wire w/ insulation
N = 28 AWG stranded wire w/ insulation
K = 26 AWG stranded wire w/ insulation
Q = 24 AWG stranded wire w/ insulation
R = 22 AWG stranded wire w/ insulation
L = 20 AWG stranded wire w/ insulation
P = 18 AWG stranded wire w/ insulation
M = 16 AWG stranded wire w/ insulation

X = No lead wires

WT = PTFE insulation required, code is added to end of part number

WLxxx = Custom wire lengths, where xxx is length in mm. Code is added to end of part number.

Call for custom wire types and lengths

Standard insulation material for 125°C rated parts is PVC. Teflon (PTFE) insulation is used on 200°C and 300°C rated parts.

Height Tolerance

9th digit of part number, default is "2"

  • Ask for "Height Matching" when using 2 or more TECs between the same two surfaces. [Height matching is more economical than specifying a tighter height tolerance code for an entire order.] Height matching assures even pressure and heat transfer across the set of TECs.
  • Typical Height Matching tolerance is +/- 0.001"
  • Choose a height tolerance that suits your application. Codes 4, 5, 6, 7, and 9 are an additional cost.


0 = Unmachined/unlapped
1 = ±0.010" [±0.25mm]
2 = ±0.007" [±0.18mm]
3 = ±0.005" [±0.13mm]
4 = ±0.0005" [±0.013mm] (For Titan metallized TECs only)
5 = ±0.0003" [±0.008mm] (For Titan metallized TECs only)
6 = ±0.002" [±0.05mm]
7 = ±0.001" [±0.03mm]
9 = ±0.004" [±0.10mm]

Tolerances shown in inches [millimeters].


Add codes to end of part number in purchase orders or specify as a separate line item that you want the TECs sealed.

  • Sealing protects the internal components from corrosion and electrical "shorts" from moist or wet environments. This includes ordinary environments where you may be taking the cold side of the TEC below the local "dew point" thereby creating condensation and/or ice on the TEC.
  • Sealing protects the internal pellets from dirt, dust, and other contaminants that may collect there over time. These contaminants may corrode the pellets or eventually create an electrical "short" therby damaging the TEC. Ask for a sealed TEC if your application is in a particularly dusty environment.
  • Sealing has a minimal effect on the TECs capability to pump heat (Q) and its maximum delta T. Typical effects are 1-2% on heat pumping capacity and 1-2 degrees on maximum delta T.
image of sealed and unsealed TEC


S = RTV moisture sealed

In the online store, there is an option for "RTV Moisture Sealing". Choose this if you want your TECs sealed.


SR = Epoxy Ruggedized Sealing

Epoxy based ruggedization seals the TEC from moisture and debris AND also strengthens the TEC against shock, vibration, and shear forces.


Sectioning (bottom plate only)

Add codes to end of part number

  • Sectioning of TEC's greater than 1" in cycling and extreme duty applications reduces thermal stresses and extends TEC life. Call for more information.
  • See examples, click here.
C1 = Bottom plate sectioned into 4 pads
C2 = Bottom plate sectioned into 9 pads
C3 = Bottom plate sectioned into 16 pads
C4 = Bottom plate sectioned into 25 pads
C5 = Bottom plate sectioned into 36 pads
C6 = Bottom plate sectioned into 49 pads
C7 = Bottom plate sectioned into 64 pads

Other Options

Add codes to end of part number

E1 = Mil spec testing and Burn-in
E2 = Custom Burn-in
R = Modified for high G forces
G1 = Top and bottom plates are gold (Au) plated (for fluxless soldering)
G2 = Top plate is gold (Au) plated
G3 = Bottom plate is gold (Au) plated
P = Polarity of wire leads is reversed
S = Sealed for moisture protection
T1 = Tinned on bottom w/ 183°C 63/37 solder
T2 = Tinned on top w/ 183°C 63/37 solder
T3 = Tinned on top & bottom w/ 183°C 63/37 solder

HS = Heat Shrink tubing on lead wires

W1 = Lead wires exit on same short side of TEC

W2 = Lead wires exit on diagonal corners of TEC

W3 = Lead wires exit on same long side of TEC

WT = PTFE insulation required (even if part is standard temp 125°C rated)

WLxxx = Custom wire lengths, where xxx is length in mm. Two different wire lengths are both indicated as follows WLxxx/xxx. Example: WL150/250 black wire is 150mm, red wire is 250mm.

More than one option code may be specified at one time.
Additional options (please call ):

• Holes
• Installed Thermocouples (where possible)
• Gold, silver, nickel, or tin plating
(metallized TEC’s only)
• Wide temperature range of pre-tinned solder options
• Shock and vibration screening
• Thermal uniformity matching
• ∆T Matching (for multi TEC sets)
• AC resistance matching to 20 milliohms
(for multi TEC sets)



  • First 3 digits are the number of couples (N and P pellet pairs) in the device.
  • 4th digit denotes metallized (0) or ceramic (1) faces See "Face Options" above.
  • 5th digit denotes the number of stages - a standard single stage device = 1
  • 6th place is a "-"
  • 7th digit denotes the maximum temperature rating of the device
    1. "4" is 110°C rated
    2. "5" is 125°C rated
    3. "6" is 150°C rated
    4. "7" is 320°C rated
    5. "9" is 200°C rated
  • 8th digit denotes lead wire type. See "Wire Type" above.
  • 9th digit denotes height tolerance of module. See "Height Tolerance" above.
  • 10th digit is an amperage multiplyer for digits 12 and 13. "1" is 1X, "0" is .1X
  • 11th place is a "-"
  • 12th and 13th digits denote the amperage (Imax) of the device
  • 14th digit denotes the series (Co. internal reference only) Using B, C, and D.
  • 15th digit denotes physical size. Rectangular devices may use two letters such as "FL" = 15x30mm.
    1. "A" is 8mm
    2. "B" is 10mm
    3. "D" is 12mm
    4. "E" is 13mm
    5. "F" is 15mm
    6. "G" is 20mm
    7. "H" is 22mm
    8. "J" is 23mm
    9. "K" is 25mm
    10. "L" is 30mm
    11. "M" is 35mm
    12. "N" is 36mm
    13. "P" is 38mm
    14. "Q" is 40mm
    15. "R" is 44mm
    16. "T" is 45mm
    17. "V" is 49mm
    18. "W" is 50mm
    19. "X" is 55mm
    20. "Y" is 59mm
    21. "Z" is 62mm
    22. "U" followed by a number denotes mini TECs. "U4" = 4mm.
  • Remaining digits are used for further options. See above.




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