Defrost heating tubes are tubular heating elements dedicated to refrigeration equipment, with their specifications and sizes highly adapted to the installation space and defrost power requirements of refrigerators, freezers, cold storage, ice makers and other equipment. They are standardized around four core dimensions: tube diameter, shape structure, length, and power/voltage, and customized special-shaped designs are also available. Below are the industry universal conventional specifications and mainstream dimensional parameters, covering more than 90% of application scenarios for household and commercial refrigeration equipment. All parameters are standard for special defrost models of refrigeration equipment.

I. Core Basic Specifications (Universal for All Types)

1. Tube Material & Diameter

(The most commonly used specification marking, directly determining installation adaptability)
Tube diameter is the core dimension of defrost heating tubes, which needs to match the reserved installation gap of evaporators and water pans of refrigeration equipment. Φ6.5mm and Φ8mm are the mainstream for household refrigeration equipment, and Φ10.7mm for commercial equipment. Without special instructions, all are 304 stainless steel seamless tubes (food-grade, resistant to condensed water corrosion).

Tube Diameter Specification	Application Scenarios	Conventional Wall Thickness
Φ6.5mm	Household refrigerators, small chest freezers, ice maker ice trays	0.4~0.5mm
Φ8mm	Household side-by-side refrigerators, upright freezers, small commercial display cabinets	0.5~0.6mm
Φ10.7mm	Large commercial freezers, cold storage evaporators, industrial refrigeration units	0.6~0.8mm
Φ12/14mm	Large cold storage, cold chain refrigeration equipment (high-power models)	0.8~1.0mm

2. Rated Voltage & Power

(Matching equipment power supply, defrost power adapted on demand)

Voltages are divided into civil AC standard and vehicle/industrial DC models. Power is positively correlated with the length and diameter of the heating tube. Single-tube power of 50~200W is mainstream for household use, and 200~500W for commercial use. The power density is controlled at 8~15W/cm (dedicated for refrigeration defrosting to avoid local overheating).

Voltage Specification	Conventional Power Range	Core Applicable Equipment
220V/240V (AC)	50W, 80W, 100W, 150W, 200W	Household refrigerators/freezers, commercial display cabinets, cold storage (civil power supply)
110V/120V (AC)	50W, 80W, 100W	Overseas version refrigeration equipment (US/EU standard)
12V/24V (DC)	20W, 30W, 50W	Vehicle-mounted freezers, RV refrigerators, mobile refrigeration equipment
380V (AC)	300W, 400W, 500W	Large industrial cold storage, refrigeration units (three-phase power)

II. Mainstream Shape Structures & Corresponding Sizes

(Classified by installation scenarios, shaped models can be directly replaced)

Defrost heating tubes feature a rigid shaped structure, with their shapes designed according to the installation positions of refrigeration equipment. Straight and U-shaped are the most universal models, accounting for more than 80%. M-shaped/special-shaped models are dedicated to commercial evaporators. All sizes refer to the effective heating length of the tube body (excluding lead wires and fixing brackets).

1. Straight Defrost Heating Tube

(The most basic model, suitable for condensed water pans, drain pipes, small evaporators)

— Core application: Refrigerator condensed water pans, freezer drain pipes, small ice maker ice trays

— Mainstream lengths: 100mm, 150mm, 200mm, 250mm, 300mm, 400mm

— Matching specifications: Mostly Φ6/8mm tube diameter, 50~100W power (220V), 300~500mm lead wire length (high-temperature resistant silicone wire)

2. U-shaped Defrost Heating Tube

(Main model for household refrigeration equipment, suitable for evaporators of refrigerators/household freezers)

— Core application: Evaporators of household double-door/side-by-side refrigerators, chest freezers, small commercial display cabinets

— Mainstream sizes (total tube height × single arm length; U-shaped opening width is mostly 80~150mm, matching evaporator fin spacing):

① Small: 150×100mm, 200×120mm (Φ6mm, 50~80W/220V, mini fridges/single-door refrigerators)

② Medium: 250×150mm, 300×180mm, 350×200mm (Φ8mm, 100~150W/220V, side-by-side refrigerators/chest freezers)

③ Large: 400×250mm, 500×300mm (Φ8/10mm, 150~200W/220V, small commercial display cabinets)

3. M-shaped (Finned) Defrost Heating Tube

(Commercial model, suitable for large evaporators)

— Core application: Evaporators of large commercial freezers, cold storage, industrial refrigeration unit heat exchangers (large fin spacing, requiring large-area defrosting)

— Mainstream sizes: Total length 800~2000mm, Φ10mm tube diameter, 200~500W power (220V/380V)

— Special design: Some tube bodies are with fins to increase heat dissipation area and improve defrost efficiency

4. Special-shaped Bent Tube

(Custom model, suitable for special installation positions)

— Core application: Special-shaped evaporators, ice maker ice trays, defrosting of air conditioner outdoor units

— Common custom shapes: L-shaped, W-shaped, annular. Sizes are customized according to the original equipment drawings, and all Φ6~10mm tube diameters are adaptable.

III. Supporting Universal Specifications (Installation/Wiring, Industry Unified Standard)

1. Lead wire: Standard equipped with high-temperature resistant silicone wire/PTFE wire (heat resistance above 200℃), length 300~500mm (1~2m customizable), wire diameter 0.75/1.0/1.5mm² (matching power).

2. Terminal block: Waterproof sealed terminals/ceramic terminal posts, adapted to the high-humidity environment of refrigeration equipment to prevent electric leakage.

3. Fixing accessories: Welded stainless steel brackets/clips, bracket height 10~20mm, spacing 50~100mm, which can be directly clamped/screwed on evaporators/water pans.

4. Protection grade: Conventional IP65 (waterproof and anti-condensation), IP67 (fully waterproof) for commercial/immersion environment models.

IV. Classic Adaptation Combinations for Household/Commercial Refrigeration Equipment (Direct Reference for Selection)

1. Household single-door/double-door refrigerators: Φ6mm U-shaped 200×120mm/250×150mm, 80/100W 220V

2. Household side-by-side refrigerators/chest freezers: Φ8mm U-shaped 300×180mm/350×200mm, 150/200W 220V

3. Small commercial display cabinets/ice makers: Φ8mm straight 300/400mm or U-shaped 400×250mm, 100/150W 220V

4. Large commercial freezers/cold storage: Φ10mm M-shaped 1000~2000mm, 300~500W 220V/380V

5. Vehicle-mounted freezers/RV refrigerators: Φ6mm straight 150/200mm, 20/30W 12V/24V

Supplementary: Custom Specification Range

If conventional models are not adaptable, manufacturers can customize according to original equipment drawings/installation space, with core customized dimensions as follows:

1. Tube diameter: Φ4~14mm

2. Length: Effective heating length 50mm~3000mm

3. Shape: Any special-shaped bent tube (L/W/annular)

4. Power: 20W~1000W (Voltage 12V~380V AC/DC all adaptable)

5. Material: 316 stainless steel, red copper tube, aluminum tube (for special corrosion/thermal conductivity requirements)

Post time: Mar-13-2026