Overview
The Silicone Rubber Heating Cable – 25 W/m is a gentle-output, long-run constant wattage heating wire in a flexible silicone jacket. At 25 W per metre it is the low-density end of our silicone family — ideal for heat maintenance rather than aggressive defrosting: long water lines that only need to stay just above freezing, insulated pipes holding a process temperature, and instrument housings that cannot take high wattage. Thanks to the lower current draw, a single circuit can reach 65 metres.
Like every wire in the range, voltage is configurable between 36 V and 240 V, the silicone jacket survives −60 °C to +200 °C, and each belt leaves our factory after resistance, hipot and insulation tests. It is part of our silicone heating cable range, manufactured in-house and exported factory-direct.
Key Features
- 25 W/m gentle output — heat-maintenance class output that holds pipe temperature without over-heating insulated runs.
- Long per-circuit reach — up to 65 m on one circuit, the longest in the silicone family.
- 36–240 V configurable — from low-voltage equipment circuits to 220 V mains trace heating.
- Full silicone construction — silicone inner insulation and outer jacket, flexible to −60 °C, stable to +200 °C.
- Alloy resistance core — copper-nickel alloy wire for even heat and durable output over time.
- Joint-free cold tail — integrated cold-tail section bends easily and terminates in a dry junction box.
Technical Specifications
| Parameter | Value |
|---|---|
| Heating element | Copper-nickel alloy resistance wire, parallel construction |
| Output | 25 W/m |
| Rated voltage | 36–240 V AC, specified at order (standard 220 V) |
| Conductor cross-section | 0.75 mm² |
| Cable cross-section | approx. 5 × 7 mm |
| Inner insulation / outer jacket | Silicone rubber / silicone rubber |
| Parallel node spacing | 0.5 m |
| Max single-circuit length | 65 m at 25 W/m |
| Withstand test | AC 3500 V, water-immersion hipot, 100% factory tested |
| Temperature range | −60 °C to +200 °C jacket; trace temperature maintained up to 150 °C |
| Control | On/off thermostat or contact thermostat matched to circuit load |
| Compliance | CE, RoHS; manufactured under ISO 9001 |
Available Options & Variants
25 W/m is the economical choice where pipes are well insulated and the climate is moderate. For frost-critical short runs, step up to the 50 W/m silicone rubber heating cable; for drainage antifreeze in between, the 40 W/m drain-line version is the middle ground. Heating length, lead length, voltage and wattage are all customer-specified — we wind the element to your drawing rather than selling a fixed stock length.
Applications
- Long water-line antifreeze — keeps insulated water mains above freezing across long residential or commercial runs.
- Process heat maintenance — holds oil, syrup or chemical lines at temperature where the fluid must not solidify.
- Meter and valve trace heating — gentle freeze protection on utility meters, pumps and valve chambers.
- Instrument and enclosure heating — low-wattage trace heating inside instrument boxes exposed to cold.
- Food and pharma environments — the smooth, cleanable silicone jacket suits washdown areas where approved.
Constant Wattage vs Self-Regulating — Which Do You Need?
This is a constant wattage heating cable: its alloy wire delivers a fixed 25 W per metre, section by section at the 0.5 m node spacing. Because the output never trims itself, the element must be ordered to length and run under a thermostat — never free-running on a fully insulated loop. If your project has variable temperatures, overlapped bends or unmeasured runs, the overlap-safe, cut-to-length self-regulating heating cable range is the better engineering fit. Well-planned, long, insulated runs are exactly where fixed-wattage silicone wire wins on price.
Installation Guide
- Confirm the total heating length against your loop drawing — the cable is ordered to length and must not be cut on site.
- Dry the pipe surface and fix the cable straight along it at the 4 or 8 o’clock position with fixing tape every 30 cm.
- Give valves and flanges an extra spiral turn; the 5 × 7 mm body bends easily around fittings.
- Keep the integrated cold tail clear of the heated zone and land it in a dry, accessible junction box.
- Fully insulate the traced run; low-output trace heating relies on insulation to hold temperature.
- Wire through an earth-leakage-protected circuit with a contact or immersion thermostat, and check resistance against the factory record before switch-on.
Safety & Certifications
The cable is CE-marked, RoHS-compliant and built under ISO 9001 quality control, with every finished unit tested for DC resistance, water-immersion hipot at AC 3500 V and insulation resistance. As a fixed-output element, its surface temperature is governed by wattage, insulation and the external control thermostat — undersized control or missing insulation is the only realistic way to push it beyond design. The silicone jacket handles moisture for outdoor duty; explosive-atmosphere applications must be confirmed with our engineers before specification.
Factory & Quality Control
SunAura has manufactured heating elements in Qingdao since 2008, supplying equipment OEMs and trace-heating contractors in over 50 countries. The silicone line runs vertically in-house — alloy wire drawing, silicone extrusion, node welding and hipot bench testing — and batch records are retained for the product’s lifetime. When a production line expands years later, replacement elements match the original build exactly.
Packaging & Shipping
Each coil is taped, coiled and packed in an export carton with its test record and declaration of conformity. Standard 220 V builds are produced to schedule; popular combinations are kept as coil stock. Shipping is by sea, air or express under EXW/FOB terms, and controllers, junction boxes and fixing tape can ride in the same shipment.
OEM/ODM & Private Label
The 25 W/m build is a favourite for OEM integration — low, predictable power that suits appliance, tank and enclosure warming products. We offer custom heating and lead lengths, custom voltages, private-label packaging and element-only supply. Send us the target surface and temperature range and we will develop the winding spec for your product.
Wholesale Pricing & How to Buy
Factory-direct wholesale pricing with volume tiers for distributors, contractors and OEM programmes. MOQ is flexible and sample coils are available for evaluation. Because this is an ordered-to-length constant wattage heating cable, quote requests should include heating length, cold-tail lead length, voltage and wattage. Request a quotation with your project parameters, or review the whole catalogue on the products hub. Pair it with a smart thermostat for automatic temperature control.
Frequently Asked Questions
Why choose 25 W/m over a higher-output silicone heating cable?
For well-insulated pipes in moderate climates, 25 W/m holds the required temperature at the lowest running cost, and it reaches 65 m on one circuit instead of 44–50 m. Choose higher output only where the pipe is thin-insulated, exposed or needs fast frost protection.
Can this cable be left on all winter?
Yes, when it runs on a thermostat or contact control set near the freezing mark. As a fixed-wattage element it should always be thermostatically controlled rather than live continuously.
Is the silicone jacket waterproof outdoors?
The silicone jacket is moisture-resistant and rated for outdoor and damp environments, and every belt passes a water-immersion hipot test. The cable is fixed to the outside of insulated pipework — it is not designed for continuous underwater submersion.
What is the maximum temperature this cable can maintain?
The silicone jacket itself is stable to +200 °C; typical antifreeze and heat-maintenance jobs hold up to around 150 °C trace temperature. Tell us your target process temperature at order and we will size the output.
Do you offer samples and private-label production?
Yes — sample coils for bench testing and OEM/ODM private-label programmes are standard. Contact sales for current sample terms.
Related Products You May Need
Pair this product with compatible SunAura components — one factory, one warranty.
Silicone Rubber Heating Cable – 50 W/m
High-temperature silicone rubber heating cable with a copper-nickel alloy core — 36–240 V custom voltage, rated for continuous use up to 150 °C, for pipe freeze protection and tank heat tracing.
Antifreeze Silicone Heating Cable for Drain Lines – 40 W/m
220–240 V antifreeze silicone cable purpose-built for drain lines and waste pipes — constant-wattage alloy core, watertight silicone jacket for wet outdoor runs.