
A Compact and Powerful Instant Hot Water System for Modern Spaces
The APUS Tankless Water Heater Electric 240V 4500W is designed for homeowners and small business owners who need reliable, on-demand hot water without the bulk and inefficiency of traditional tank systems. Built specifically for under-sink and point-of-use applications, this compact heater delivers hot water in seconds while reducing energy consumption and eliminating standby heat loss.
In this comprehensive review, we examine the performance, design, safety systems, installation requirements, and overall value of the APUS 4.5KW instant water heater.
Product Overview
The APUS 4.5KW electric tankless water heater is engineered to provide fast and efficient hot water for single-point applications such as:
- Kitchen sinks
- Bathroom sinks
- Laundry rooms
- Salons
- Cafés
- Utility wash stations
Instead of storing heated water in a tank, this unit heats water instantly as it flows through the system. That means no waiting and no wasted energy keeping water warm when it is not being used.
Technical Specifications Table
Below is an accurate product data table based on manufacturer specifications.
| Specification | Details |
|---|---|
| Brand | APUS |
| Power | 4500 Watts |
| Voltage | 240V |
| Required Breaker | 30A Double-Pole |
| Recommended Wire | 12 AWG |
| Product Dimensions | 6.5″ W x 8.66″ H x 2.6″ D |
| Fitting Size | 1/2″ NPT |
| Temperature Range | 85°F – 131°F |
| Efficiency Rating | 99.8% |
| Installation Type | Under Sink / Point of Use |
| Control Type | LED Touchscreen |
| Heating Element | Cast Aluminum |
| Color | Gray |
| Safety Features | Overheat Protection, Dry-Burn Prevention, Anti-Leakage, Shockproof System |
Design and Build Quality
One of the strongest advantages of the APUS electric tankless heater is its ultra-compact design. Measuring just 8.66 inches in height and 6.5 inches in width, this unit fits easily beneath most sinks without requiring additional cabinetry modifications.
The slim 2.6-inch depth makes it ideal for tight installations in apartments, RV-style setups, or commercial counters. Its gray exterior offers a clean, modern aesthetic that blends well with contemporary plumbing layouts.
Cast Aluminum Heating Element
The internal heating element is made of high-quality cast aluminum. This material offers:
- Excellent heat transfer
- Resistance to corrosion
- Reduced scale buildup
- Improved long-term durability
This construction helps extend the lifespan of the heater while maintaining consistent performance.
Performance and Heating Capability
Instant Hot Water in 3 Seconds
The APUS 4.5KW tankless system delivers hot water in approximately 3 seconds. This immediate heating capability eliminates:
- Preheating time
- Tank refill delays
- Standby heat loss
The unit is ideal for single sink usage, where consistent temperature and rapid response are essential.
Temperature Range
Users can adjust water temperature between 85°F and 131°F using the LED touchscreen interface. This range is sufficient for:
- Hand washing
- Dishwashing
- Light cleaning
- Utility washing
The heater is not intended for whole-house applications but performs reliably for point-of-use setups.
Smart Energy Efficiency
Traditional water heaters continuously heat stored water, leading to energy waste. The APUS tankless heater uses self-modulating technology that adjusts power output according to:
- Incoming water temperature
- Water flow rate
With an efficiency rating of 99.8%, this system heats water only when needed. This can potentially reduce electricity usage by up to 50% compared to traditional tank heaters in single-point applications.
Key energy benefits include:
- No standby energy loss
- Lower monthly electricity bills
- Reduced environmental impact
LED Touch Control System
The integrated LED touchscreen offers precise temperature control. The interface is:
- Responsive
- Simple to operate
- Easy to read
Users can quickly adjust settings to match their needs without complicated programming.
The digital display clearly shows the water temperature, allowing for consistent and accurate control.
Safety Features and Protection Systems
Safety is a critical factor in any electric appliance, and APUS integrates multiple protective systems.
1. Overheat Protection
The heater automatically shuts down if internal temperatures exceed safe limits. This prevents damage to internal components and reduces fire risk.
2. Dry-Burn Prevention
If water flow is interrupted, the system detects the condition and stops heating. This prevents the heating element from operating without water, which could otherwise cause severe damage.
3. Anti-Leakage Technology
Built-in anti-leakage protection helps safeguard against electrical hazards caused by moisture or improper connections.
4. Shockproof Internal System
The anti-electric wall design provides additional insulation and protection against electric shock.
These safety features make the APUS tankless heater suitable for residential and light commercial use.
Installation Requirements
Electrical Requirements
This heater must be:
- Hardwired to 240V
- Connected to a 30A double-pole breaker
- Installed using 12 AWG wire
It is not a plug-in unit. Professional installation by a licensed electrician is strongly recommended.
Plumbing Setup
The unit includes:
- Pre-drilled mounting holes
- 1/2″ NPT fittings
Installation is straightforward for experienced plumbers. The compact size makes mounting under sinks simple.
Ideal Applications
The APUS 4.5KW tankless water heater is best suited for:
Kitchen Sinks
Provides hot water for dishwashing and food prep cleanup without waiting for a distant tank heater.
Bathroom Sinks
Delivers instant hot water for handwashing and grooming.
Laundry Areas
Perfect for small wash basins where immediate hot water is needed.
Commercial Counters
Useful in salons, cafés, and small retail spaces where a single sink requires reliable hot water.
Advantages of the APUS Tankless Water Heater
- Instant 3-second hot water delivery
- 99.8% energy efficiency
- Ultra-compact space-saving design
- LED digital touchscreen control
- Durable cast aluminum heating element
- Multiple advanced safety protections
- No standby heat loss
- Lower long-term energy costs
Limitations to Consider
- Designed for single-point use only
- Requires professional electrical installation
- Not suitable for showers or whole-house supply
- 240V dedicated circuit required
Understanding these limitations ensures proper application and satisfaction.
Comparison with Traditional Tank Heaters
| Feature | APUS Tankless | Traditional Tank Heater |
|---|---|---|
| Heating Time | 3 seconds | Several minutes |
| Energy Efficiency | 99.8% | Lower due to standby loss |
| Space Requirement | Very compact | Large tank |
| Hot Water Supply | On-demand | Limited by tank size |
| Installation | Electrical hardwire | Plumbing + tank placement |
The APUS system excels in efficiency and space savings for localized use.
Maintenance and Longevity
Maintenance requirements are minimal. However, periodic checks are recommended:
- Inspect electrical connections
- Check for scale buildup in hard water areas
- Ensure water flow remains unrestricted
The corrosion-resistant heating element reduces scaling, which extends service life.
User Experience
Customers seeking an under-sink instant water heater appreciate:
- Quick response time
- Consistent temperature
- Easy-to-read LED display
- Compact installation
The quiet operation also makes it suitable for residential environments.
Who Should Buy This Heater?
The APUS Tankless Water Heater Electric 240V 4500W is ideal for:
- Apartment dwellers
- Small homeowners
- Office managers
- Salon owners
- Café operators
- Anyone needing dedicated sink hot water
It is not recommended for large family whole-house systems but excels in localized installations.
Final Verdict
The APUS Tankless Water Heater Electric 240V 4500W stands out as a highly efficient, compact, and reliable solution for point-of-use hot water needs. Its instant heating capability, energy-saving technology, and comprehensive safety systems make it a strong contender in the under-sink electric tankless category.
For kitchens, bathrooms, or commercial sinks requiring immediate hot water without bulky storage tanks, this 4.5KW system offers impressive performance in a remarkably small footprint.