Rasonic RWH-CT21L Black 21L Rapid Heating Electric Water Heater-Central Type
The Rasonic RWH-CT21L Rapid Heating Electric Water Heater is a high-performance central type water heater designed for efficient hot water supply. Featuring a powerful 3,000W heating element and a 19-liter stainless steel water tank, this unvented unit delivers rapid heating to 75℃ with a preheat time of approximately 5 minutes to reach 40℃. Its slim black tempered glass design offers a modern aesthetic while optimizing space. Built with durability and safety in mind, it includes multiple protection mechanisms and comes with a 10-year warranty on the stainless steel water tank.
Key Features
- Rapid Heating Technology: Equipped with new rapid heating technology to significantly increase heating speed and efficiency, shortening preheat waiting times.
- 19L Capacity: Provides ample hot water for showering, ensuring a stable and comfortable supply.
- Slim & Stylish Design: Its sleek, space-saving profile with a sophisticated black tempered glass cover integrates seamlessly into modern interiors.
- Intuitive Control: Features an LED temperature display for clear readings and a knob control for precise temperature adjustment.
- Water Efficiency: A built-in flow-restrictor device maintains water flow intensity while reducing overall water consumption.
- Stainless Steel Water Tank: Ensures long-term durability and resistance to corrosion.
- Special Air Pressure Shower Head: Designed for safe, reliable, and durable performance.
Technical Specifications
- Model: RWH-CT21L
- Type: Rapid Heating Unvented Electric Water Heater - Central Type
- Color: Black Tempered Glass
- Rated Power: 3,000W
- Rated Voltage: 220V
- Frequency: 50Hz
- Water Tank Capacity: 19 Litres (Approx.)
- Maximum Water Temperature: 75℃
- Preheat Time: Approx. 5 minutes (to reach 40℃)
- Product Dimensions (W x D x H): 420 x 170 x 655 mm
- Net Weight (Approx.): 17.2 kg
- Full Tank Weight (Approx.): 36.2 kg
- Maximum Water Supply Pressure: 600kPa (6 bar)
- Pipe Connection: 1/2"
- Output Pipe Connection: x 2 (Cold & Hot water supply)
- Waterproof Standard: IPX1
Safety & Durability
- Automatic Temperature Control: Maintains desired water temperature for consistent comfort.
- Pressure & Temperature Relief Valve: Ensures safe operation by releasing excess pressure or temperature (99℃/1,000kPa).
- Overheat Protection: Automatically shuts off if water temperature exceeds 110℃, preventing potential hazards.
- Anti-vacuum Valve Device: Effectively prevents hot water in the tank from siphoning back under abnormal conditions, protecting the water tank and heating element.
- Product Warranty: 1-year warranty.
- Water Tank Warranty: 10-year warranty on the stainless steel water tank.
Specifications are subject to change without prior notice.
The product information above is for reference only; everything is subject to the brand's official website.
Rasonic RWH-CT21L Black 21L Rapid Heating Electric Water Heater-Central Type Review
Installation
| *Water Heater Standard installation fee | |||
| Site inspection(No return) | Ask For Agent | ||
| Instantaneous Water Heater | Ask For Agent | ||
| Shower Unit Storage Water Heater | Ask For Agent | ||
| Central System Storage Water Heater (8 gal or below) | Ask For Agent | ||
| Central System Storage Water Heater (10 gal or above) | Ask For Agent | ||
| Horizontal Installation charge | Ask For Agent | ||
| Uninstall and take away the old machine | Ask For Agent | ||
| *Instantaneous Water Heater Standard installation include: | |||
| a.3ft power cord (Surface wiring) | |||
| b.4ft white plastic coated copper pipe for hot and cold water | |||
| *Shower Unit Storage Water Heater Standard installation include: | |||
| a.10ft power cord (Surface wiring) | |||
| b.4ft white plastic coated copper pipe for hot and cold water & 2 Copper pipe accessories | |||
| *Central System Storage Water Heater Standard installation include: | |||
| a.10ft power cord (Surface wiring) | |||
| b. 3ft white plastic coated copper pipe for hot and cold water & 7 Copper pipe accessories | |||
|
|
|||
| *Water Heater extra fee(For reference only) | |||
| White plastic coated copper pipe for hot and cold water | $30 / ft | ||
| White plastic pipe with drain valve (below 8ft) | $100 | ||
| Copper pipe accessories | $30/ each | ||
| Air Bleed valve | $400 | ||
| Make a new water input | $200 | ||
| Split the electricity from one socket(include the 10ft Power cord) | $800 | ||
| Power cord extension | $20 / ft | ||
| Power cord extension(3-phase*4) | $80 / ft | ||
| Stairs fee | $30 (10steps) | ||
| Installation surcharge for Tung Chung / Ma Wan area | $100 | ||
| Installation surcharge for Discovery Bay area | $400 | ||
| REMARK | |||
| *Other agents or other contractors deilvery fee/installation fee will be different. For more information, please contact our inquiry | |||
| Standard power socket be provlded by customer | |||
| If extra installation fee is not in the installation list,need to quote. | |||
| Location of installation are decided by customer.Any re-location after installation shall be subjected to extra charge. | |||
| Delivery | |
|
| Installation Schedule | |
|
Why us?
Why Choose BBE?
The trusted choice of over 100,000 Hong Kong families, dedicated to delivering excellence in quality and service.
Visit our flagship stores in Mong Kok, Causeway Bay, and Tuen Mun to experience over 1,000 appliances from Europe, the US, and Japan. Our consultants are ready to provide expert installation advice.
Awarded store with nearly 30,000 authentic reviews. We guarantee transparent and competitive pricing.
Get instant professional support via WhatsApp. From spec comparisons to dimension queries and installation questions, our expert team provides immediate answers.
No parallel imports! All appliances are official Hong Kong distributor stock, coming with at least a 1-year original manufacturer warranty and a 7-day defective replacement guarantee.
Our service quality is recognized by the industry and top brands alike. We have been honored with the Towngas TGC Sales Gold Award and Daikin’s Diamond Dealer status, alongside prestigious partner and distributor awards from Gree, Carrier, and Philips Smart Lock.
Our site uses SSL encryption and supports various e-payments. We offer one-stop professional delivery and installation services for a worry-free experience.

















































Extend Product Warranty 
.png)