“PTC heater” isn’t one product — it’s a family of five architectures that share a heating material but solve very different mechanical and thermal problems. Picking the wrong one costs a redesign cycle later.

Start with what you’re actually heating

Before comparing part numbers, answer one question: is the heat going into a liquid, into moving air, or directly into a solid surface or component through contact? That single answer eliminates most of the catalog.

Liquid Heater — four mounting styles

Once you know it’s a liquid application, the mounting geometry decides the subtype:

• Flow-through type — liquid passes through the heater body itself; best for inline heating where you want minimal added volume in the flow path.
• Immersion type — the element sits submerged directly in a tank or reservoir; simplest to install where you already have an open vessel.
• Bottom-mounted type — flat element mounted to the underside of a tank wall, heating through the vessel wall without direct liquid contact on the element itself — useful when you can’t put electrical components in the fluid path.
• Pipe-jacket type — wraps around an existing pipe; retrofit-friendly when you can’t modify the fluid path at all.

Air Heater — forced vs. convection

Forced-air type heaters are paired with a fan and sized for fast, directional heat delivery — think defrost or rapid cabin warm-up. Convection type heaters rely on natural airflow and are better suited to enclosures or spaces where a fan isn’t practical or adds unwanted noise and power draw.

Cased Heater — the housing material is the trade-off

Insulated Heater — for flexible, wrap-around surfaces

The insulation-wrapped type is a thin, flexible element — the choice when the heating surface isn’t rigid: cylindrical wraps, seat structures, or tubing where a cased heater’s fixed geometry won’t conform.

Heating Chip — for embedded, space-constrained assemblies

Heating chips are the bare PTC ceramic element with a lead configuration but no housing — used when your own product’s enclosure provides the mechanical protection and you just need the raw heating element to embed. The lead configuration matters here:

• Side-edge lead wire type — leads exit from the ceramic’s edge, useful for the lowest possible profile.
• Single-surface lead wire type — both leads on one face, simplifies PCB or bracket mounting.
• Dual-surface electrode type — electrodes on opposite faces, typically the simplest to sandwich between two contact plates.

What to have ready before you request samples

• 01
  What medium is being heated, and roughly what volume or airflow
• 02
  Available mounting space and geometry constraints
• 03
  Target stable temperature and acceptable warm-up time
• 04
  Operating voltage and any power budget limits
• 05
  Required certifications for your target market (UL, CE, RoHS, CQC)

With those five answers, our team can usually recommend a starting architecture and turn around samples without multiple rounds of back-and-forth. If you want the physics behind why PTC elements hold a stable temperature without a controller, see How PTC Ceramic Heaters Self-Regulate Temperature.