TEC2-25408 40mm Double Thermoelectric Cooler Peltier Cooling Plate (1PCS)

TEC2-25408 40mm Double Thermoelectric Cooler — Fitment & Sourcing Guide

By Moritta Chen · KOEED Sourcing Engineer · Fact-checked against unit nameplate data · Every quotation is confirmed in writing before dispatch

The TEC2-25408 is a two-stage (cascade) thermoelectric cooling module in the 40 mm footprint class — the kind of part that is easy to buy and surprisingly easy to buy wrong. A cascade Peltier module is not a drop-in substitute for a single-stage one on the same heat sink, and the code stamped on the ceramic tells you considerably less than most listings imply. This page explains what the TEC2-25408 designation does and does not tell you, which fields actually decide whether a module will fit your assembly, and how KOEED confirms the match in writing before anything is dispatched.

The TEC2 naming code: what it identifies and where it stops

Thermoelectric module codes are not standardised across manufacturers. In the common listing convention, the leading TEC marks the part as a thermoelectric cooler, and the digit that follows tells you how many stages are stacked thermally in series — so TEC2 points to a two-stage, cascade construction rather than a single-layer module with one pellet array. The numeric tail is a manufacturer or listing identifier used to distinguish variants within that maker's own range.

Read that as a family indicator, not a specification. Two suppliers can both ship a module badged "TEC2" with different pellet counts, different ceramic footprints, different lead exits and a different electrical window. That is why a quote built from the code alone — without the markings on your actual part — is a quote that can be technically correct and still not fit.

Two-stage versus single-stage: why the geometry changes the answer

A cascade stack places two stages in thermal series — a cold stage sitting on top of a warmer stage — so the temperature differential achievable across the whole stack is larger than one stage can produce on its own. That is why two-stage modules turn up in sensor and detector cooling, small optical and imaging assemblies, and point-of-use laboratory cooling, where a modest heat load has to be pushed well below ambient.

The trade-off is a heavier duty cycle on everything downstream of the module. The stack has to reject what the cold stage pumps plus its own input power, so the hot-side heat sink, the interface material, the clamping method and the ambient path all matter more than they do on a single-stage build. A module that looks like "the same 40 mm part" as the one it replaces can still be the wrong component if the stack height, the lead exit face, or the electrical window of your existing driver does not line up.

Treat the "40mm" in the listing title as a footprint class claim rather than a verified dimension for every lot. Measure the ceramic envelope and the total stack height with calipers on the part you actually hold.

Where the published documentation stops

This table provides no numeric values — we do not underwrite unsourced numbers.

For trade-code-style modules the public record is a marketplace listing, not an OEM datasheet. Ratings such as maximum current, maximum voltage, maximum heat pumping capacity and maximum temperature differential only carry meaning when they are tied to a specific manufacturing lot and to that module's own label or document pack. A figure lifted from a sister model, an aggregator page, or a rounded "typical" value is exactly the kind of number that fits neatly on paper and fails inside an assembly. So instead of a specification table, here is the field list that genuinely gates compatibility for this part family.

So what: the marking, the stack geometry and the rejection path together decide whether a given module will fit and hold temperature — and none of the three can be confirmed from a public catalogue listing. Email the module marking and photographs to Moritta@KOEED.COM and we will return the datasheet or document pack that matches your lot, or tell you plainly that none exists and quote on the verified geometry instead.

Confirm fitment in ten minutes: a seven-point check

1. Photograph the module from the cold face, the hot face, one side, and straight on to the marking. Include something for scale.
2. Measure the ceramic footprint (length and width) and the total stack height with calipers, and note the thickness of each visible stage if the layers are separable.
3. Record the lead exit face, lead length, termination style and how polarity is marked on the body.
4. Transcribe the marking character by character — including any suffix, batch or date code.
5. Note the driver: model, rated voltage, rated current, and whether control is linear or PWM.
6. Describe the hot side: heat sink type, fan position and spacing, ambient conditions, interface material and clamping method.
7. State the cold-side heat load, the target temperature, the quantity required and your delivery window.

How KOEED quotes a trade-code module

Because the code alone cannot carry the specification, we build the quotation from your part. Send the seven items above and our sourcing engineers match the module against the lot documentation we can obtain, flag any field that remains unverifiable, and put the confirmation in writing on the quotation. Nothing is dispatched on an assumption about stack height, lead routing or electrical window.

We can also quote the parts that live around the module — replacement heat sinks, thermal interface material, drivers and mounting hardware — so the whole cooling path is specified together rather than assembled from guesses. Units are supplied per piece, and orders ship worldwide with the accompanying paperwork. Typical first response is under 24 hours.

Frequently asked questions

Is TEC2-25408 a universal part number?

No. The "TEC2" prefix describes the construction family — a two-stage cascade — and the numeric tail is a maker-specific listing identifier. Two modules with the same code from different sources can differ in footprint, stack height and electrical window.

Can I replace a single-stage module with a two-stage TEC2 module?

Only if the rest of the cooling path can take it. A cascade stack rejects appreciably more heat at the base, so the existing heat sink, fan and interface may no longer be sufficient, and the driver current may fall outside the module's window. Confirm the hot-side path before you commit.

Why don't you publish voltage, current or temperature-differential figures?

Because no public, model-keyed datasheet exists for this trade code. We would rather show you the fields that decide fit than print a number we cannot trace to a document. A figure without a source is a liability, not a specification.

What if my module carries no readable marking?

Send the photographs, caliper measurements and your application details. We will match by geometry and duty rather than by code, and describe clearly what has been verified and what has not.

Do you supply the heat sink, driver and interface material as well?

Yes — send the cold-side load and the space envelope and we will quote the surrounding hardware together with the module, so clamping force, interface thickness and driver range are considered as one assembly.

What to send with your enquiry

• Nameplate or module marking — exact model, type and any batch or date code
• Photographs of the cold face, hot face, lead exit and marking, with a scale reference
• Dimensions: ceramic footprint, total stack height, lead length
• Electrical data: driver rated voltage, rated current, linear or PWM control
• Application data: cold-side heat load, target temperature, hot-side rejection path
• Quantity and required delivery window

Email these to Moritta@KOEED.COM for fitment confirmation.