NF Group High Voltage Coolant Heater 400V PTC Coolant Heater 700V PTC Electric Coolant Heater

The vehicle PTC coolant heater is a core component of new energy vehicle thermal management systems, serving as an intelligent and safe electric water heater. By heating the coolant (antifreeze), it delivers a stable and reliable heat source for both cabin heating and power battery thermal conditioning. Water‑based PTC heaters have become the market mainstream due to their high safety, excellent thermal capacity, and seamless compatibility with automotive A/C systems.

High Voltage Coolant Heater Working Principle

The core heating element is a PTC (Positive Temperature Coefficient) thermistor ceramic. Its operation relies on the unique resistance‑temperature characteristic: at low temperatures, resistance is low, allowing high current to rapidly generate heat for quick cold‑start heating. As the temperature rises, resistance increases sharply, causing current and power to drop automatically. This self‑limiting feature enables the heater to maintain a safe temperature without complex control systems, fundamentally eliminating overheating risks.

PTC Electric Coolant Heater Core Structure

A typical PTC water heater consists of a PTC heating pack (comprising ceramic heating elements, electrodes, and insulation), a heat exchanger with coolant flow channels, a controller that receives vehicle signals to precisely adjust heating power, and high/low voltage connectors. The critical safety design is water‑electricity separation: the PTC ceramic is physically isolated from the coolant, ensuring that live parts never contact the fluid, thus preventing leakage and short circuits and meeting stringent automotive high‑voltage safety standards.

EV Liquid Heater Key Advantages

Safety and reliability – besides physical separation, the self‑limiting property eliminates open flames and overheating, and the product typically includes over‑voltage, over‑current, over‑temperature, and dry‑heating protection. High efficiency – thermal efficiency can reach up to 85%, and the intelligent control system adjusts power based on actual demand to avoid waste. Rapid heating – fast response even at low temperatures. Precise temperature control – achieving ±2 °C or better accuracy. Long service life – stable PTC ceramics resist oxidation, with a design life of 8 years.

Water High Voltage Heater Main Applications

Cabin heating (heated coolant flows to the heater core), battery thermal management (preheating the battery pack to optimal temperature for improved charge/discharge performance and extended range), and auxiliary heating (fuel cell preheating, vehicle defrosting, etc.).

Hebei Nanfeng Automobile Equipment (Group) Co., Ltd., established in 1993, is a group company with six factories. We are a major supplier of new energy vehicle components in China and the designated supplier for Chinese military vehicles. Our main products include high‑voltage coolant heaters, electronic water pumps, BTMS, electric air compressors, EPS, EHPS, electric A/C compressors, three‑way valves, parking heaters, parking A/C units, plate heat exchangers, and more.

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