NF Group 7KW Battery Coolant Heater 400V High Voltage PTC Heater 540V PTC Coolant Heater 600V PTC Water Heater

In modern electric and hybrid vehicles, efficient thermal management is essential for optimizing performance and driving range. The PTC water heater plays a pivotal role in this system, functioning as an intelligent and fail‑safe electric liquid heating unit. By raising the temperature of the antifreeze coolant, it ensures a steady and dependable thermal supply for both the passenger cabin and the high‑voltage battery pack. The water‑based PTC variant has firmly established itself as the industry favourite, owing to its strong safety credentials, ample heat‑retention capacity, and smooth integration with vehicle climate‑control networks.

PTC Water Heater Working Principle

At the core of the device lies a PTC (Positive Temperature Coefficient) ceramic thermistor. The PTC material exhibits a positive temperature coefficient, meaning its electrical resistance increases significantly as temperature rises – a property that guarantees inherent protection. At low ambient temperatures, the resistance is minimal, allowing a heavy current to flow and deliver rapid heating, which is ideal for cold‑start situations. As the temperature climbs, the resistance surges, automatically reducing current draw and power output. This self‑regulating behaviour keeps the heater within a safe operating envelope without requiring sophisticated external controls, thus completely eliminating the danger of overheating.

High Voltage PTC Heater Core Structure

The main assembly comprises a PTC heating block (formed from ceramic plates, conductive electrodes, and insulating layers), an aluminium heat exchanger featuring optimised internal passages for smooth coolant circulation, an electronic controller that interprets vehicle‑side commands to modulate heating intensity, and dedicated high‑voltage and low‑voltage connectors. A vital safety feature is the complete physical segregation of the energised components from the coolant circuit – no live part ever contacts the liquid. This design effectively rules out electrical leakage and short circuits, thereby fulfilling the stringent high‑voltage safety requirements of the automotive sector. Additionally, the heat exchanger’s finned structure maximises heat transfer while minimising pressure drop, enhancing overall system efficiency.

Battery Coolant Heater Key Benefits

The unit delivers multiple advantages. From a safety perspective, beyond the isolation and inherent self‑limitation, it also incorporates protective measures against over‑voltage, over‑current, over‑temperature, and dry‑run conditions. Energy performance is excellent – up to 85 % of electrical input is converted into useful heat, and the intelligent control logic continuously adjusts power in real time to avoid wasteful consumption. The heater responds very quickly even in sub‑zero environments, maintains temperature precision within ±2 °C, and offers an extended service life of 8 years, thanks to the oxidation‑resistant nature of the PTC ceramics. Moreover, the system operates with negligible noise and requires hardly any maintenance over its lifetime.

PTC Coolant Heater Main Applications

Typical use cases include: cabin heating, where the hot fluid flows through the heater core to warm the interior; battery preconditioning, which raises the pack’s temperature before charging or driving to boost efficiency and extend range; and auxiliary functions such as fuel‑cell preheating and windscreen defrosting.

Hebei Nanfeng Automobile Equipment (Group) Co., Ltd., founded in 1993, now operates six manufacturing bases. We are a premier supplier of new‑energy vehicle components in China and are also an accredited vendor for the country’s military vehicle programmes. Our extensive product line covers high‑voltage coolant heaters, Ev Coolant Pump, BTMS, electric air compressors, EPS, EHPS, electric A/C compressors, three‑way valves, parking heaters, parking A/C units, plate heat exchangers, and many other related items. We hold ISO/TS 16949 certification and continuously invest in R&D to address evolving market demands. Furthermore, we can custom‑produce PTC heaters to meet diverse customer specifications, and we are also able to supply matching water pumps and electronic valves as complete system solutions. We warmly welcome inquiries from all interested customers and look forward to providing further assistance.