Choosing a point-of-use water heater for an apartment can help get hot water to a distant sink faster without replacing the building’s main water heater. The key is matching the unit to the fixture and your apartment’s electrical capacity. The compact tankless models below are designed mainly for one sink or water point, and several need dedicated hardwired circuits—so check with your landlord and a licensed electrician before buying.
Table of Contents
Quick Comparison
| Product | Power | Best For | Key Installation Detail |
|---|---|---|---|
| ThermoMate 4.5kW Under-Sink Tankless Heater | 4.5kW, 120V | A sink with room for a compact wall-mounted unit | Hardwired; listed requirements include a 40A double-pole breaker and 8 AWG minimum wire |
| ThermoMate 3.5kW Tankless Heater | 3.5kW, 120V | Light-duty use at a single sink | Hardwired; requires a 32A double-pole breaker and 10 AWG minimum wire |
| CAMPLUX 4.5kW Point-of-Use Heater | 4.5kW, 120V | One sink where adjustable temperature control is useful | Hardwired; listed requirements include a 40A circuit breaker and 10 AWG wire |
| Westinghouse 11kW Wi-Fi Tankless Heater | 11kW, 240V | A single water point needing more output, if the electrical supply allows | Dedicated 60A double-pole breaker and 8 AWG wire |
| CAMPLUX 6kW Point-of-Use Heater | 6kW, 240V | A sink where a 240V circuit is available | Hardwired; requires a 30A breaker and 10 AWG wire |
Our Picks: Best Point Of Use Water Heaters For Apartments reviews
ThermoMate 4.5kW: A Compact Choice for a Sink
This compact ThermoMate is a 120V tankless heater intended for a point-of-use fixture, such as a kitchen or bathroom sink. It heats water on demand rather than storing it in a small tank, and its temperature setting ranges from 85°F to 131°F. A digital display and touch controls let you adjust the set temperature.
At about 10.95 by 7.4 by 2.52 inches, it can fit in some tight cabinet spaces. The product description lists a stainless-steel water tube and a cast aluminum heating element separated from the water line. Its stated activation flow range is 0.26 to 1.0 gallons per minute, so it is best thought of as a single-sink option rather than a whole-apartment heater.
The main trade-off is the electrical work. This unit is not a plug-in appliance: its listed requirements include hardwiring, a 40A double-pole breaker, and at least 8 AWG wire. Those requirements may be difficult to accommodate in an apartment, and the product information should be checked against the installation manual and the property’s wiring before purchase.
Pros:
- Compact size suits some under-sink installations.
- Temperature display and touch controls make adjustments straightforward.
- On-demand design avoids keeping a tank of water hot.
- Designed for a low-flow, single-fixture application.
Cons:
- Requires hardwiring and a substantial dedicated circuit.
- Not intended to supply multiple fixtures at once.
Verdict: Consider this model for one sink if you have permission and an electrician confirms the listed circuit requirements can be met.
ThermoMate 3.5kW: A Smaller Option for Light Sink Use
This 3.5kW ThermoMate is a small 120V tankless heater for an under- or over-sink faucet. It has a temperature setting range of 86°F to 131°F, a digital display, and self-modulating power that adjusts to changes in water flow and inlet temperature. Its listed flow range is 0.4 to 0.66 gallons per minute, making it a better match for modest, single-sink demands than for a shower or several fixtures.
The unit measures about 7.9 by 6.4 by 2.5 inches, so it may be easier to fit in a cramped cabinet than the larger 4.5kW models. Some owners have found compact point-of-use heaters useful for reducing the wait for hot water at a distant sink. That convenience depends on proper sizing and installation, and a low-output unit may not keep up with a high flow rate or extended use.
This heater must be hardwired and cannot simply be plugged into a standard outlet. The supplied product information specifies a 32A double-pole breaker and 10 AWG minimum wire. Confirm those details with the installation instructions and a qualified electrician before planning an apartment installation.
Pros:
- Smaller body can fit in tighter spaces.
- Self-modulating operation responds to flow and inlet temperature.
- Digital temperature control offers precise settings.
- Designed for low-flow use at a single sink.
Cons:
- Its stated flow range limits it to light-duty use.
- Requires hardwiring and a dedicated high-amperage circuit.
Verdict: Choose this model if compact size and light sink use matter more than higher flow capacity, and your electrical setup can support it.
CAMPLUX 4.5kW: Adjustable On-Demand Heat for One Sink
This CAMPLUX is another 4.5kW, 120V tankless unit designed for a single sink. It has a digital temperature display, touch controls, and a self-modulating design that adjusts power based on flow and temperature. The listed minimum activation flow is 0.26 gallons per minute, while the product description gives a 50°F temperature rise at 1 gallon per minute.
Its dimensions are about 10.95 by 7.4 by 2.52 inches, similar to the ThermoMate 4.5kW model. CAMPLUX lists dry-combustion protection and a two-year limited warranty. It may suit a bathroom or kitchen sink where you want adjustable temperature control without adding a storage tank.
Installation details deserve special attention. The supplied description says the unit must be hardwired and lists a 40A circuit breaker and 10 AWG wire. Since the listed wiring details differ from the ThermoMate 4.5kW specifications, do not assume they are interchangeable; confirm the exact requirements for this model in its manual and with an electrician. Its output is also intended for one water point, not simultaneous use around an apartment.
Pros:
- Self-modulating operation adjusts power to changing conditions.
- Digital display and touch controls simplify temperature setting.
- Low listed activation flow may suit a sink with a modest faucet flow.
- Includes a two-year limited warranty, according to the product information.
Cons:
- Hardwired installation may be a barrier in a rental apartment.
- Product information should be checked carefully for circuit and wire requirements.
Verdict: This is a reasonable single-sink candidate if its exact electrical requirements fit your home and you can get approval to install it.
Westinghouse 11kW: More Output and Smart Controls
The Westinghouse is a larger 11kW, 240V tankless heater with Wi-Fi, app control, and compatibility with Alexa and Google Home. It is wall-mounted and has a temperature-memory feature that restores the last setting after a power outage. The product information lists a minimum start-up flow of 0.53 gallons per minute and describes a 2.6-gallon-per-minute flow when inlet water is 62°F and the outlet is set to 105°F.
That higher stated output makes this a different kind of option from the compact 120V sink heaters. The manufacturer presents it as suitable for a single water point, including a shower under the stated conditions, but actual output depends on incoming water temperature and flow. It should not be treated as a whole-apartment solution based on the available specifications.
The main concern for apartment buyers is the electrical demand: the listed installation calls for 240V, a dedicated 60A double-pole breaker, and 8 AWG wire. The unit is ETL certified according to the product description and lists protections for issues such as overheating and dry firing. Even so, this is a substantial electrical project, so check building rules, available service, and professional installation before considering it.
Pros:
- Higher stated output than the 120V sink-focused models.
- Wi-Fi, app control, and voice-assistant compatibility.
- Temperature memory and wall-mounted design.
- Product information lists multiple safety protections and ETL certification.
Cons:
- Requires a dedicated 240V circuit with a 60A breaker.
- Likely to be more installation work than a small sink-only unit.
Verdict: Consider the Westinghouse only if you need more output at one water point and an electrician confirms your apartment can support its demanding 240V circuit.
CAMPLUX 6kW: A 240V Option for a Sink
This 6kW CAMPLUX is a 240V tankless heater designed for sinks and small households. It has a touch control panel, displays water temperature and inlet flow, and adjusts power based on demand. The product information lists a maximum temperature of 131°F and a flow rate of 1.5 gallons per minute; the description also states a 50°F temperature rise at 1 gallon per minute.
At about 10 by 7 inches, it is a compact wall-mounted unit. Its listed features include overheat protection and a cast aluminum heating element, and the product description says the water line is separated from the electrical pathway. Compared with the 120V models, it requires a 240V supply, which may offer a practical middle ground for a sink installation when that circuit is already available.
It must be hardwired and calls for a 30A circuit breaker and 10 AWG wire. That is still a significant installation requirement, and a 240V connection should not be assumed to be available near the sink just because the apartment has other 240V appliances. It is also a point-of-use heater, not a replacement for a central system serving multiple fixtures.
Pros:
- Higher listed flow rate than the 120V sink models.
- Self-modulating operation and touch temperature controls.
- Compact wall-mounted design.
- Product information lists overheat protection and a separated water pathway.
Cons:
- Requires a hardwired 240V circuit.
- Actual temperature rise and flow depend on incoming water conditions.
Verdict: Choose this model when you want more sink capacity than a small 120V unit can offer and your electrician confirms a suitable 240V circuit is available.
How to Choose a Point-of-Use Water Heater for an Apartment
Decide Which Fixture Needs Hot Water
Point-of-use heaters are installed close to the fixture they serve. Start by identifying whether you want faster hot water at one bathroom sink, a kitchen sink, or another single water point. These models are not automatically able to serve multiple fixtures at once. If your goal is to heat water for a whole apartment, check whether a point-of-use unit is the right type of system at all.
Match the Heater to Your Hot-Water Demand
Flow rate and temperature rise work together. A heater may provide less temperature increase when water moves through it faster, and colder incoming water can also affect the result. Compare the manufacturer’s flow and temperature-rise information with the faucet or fixture you plan to use. A low-flow sink may work well with a smaller model, while a shower generally needs more output.
Check Voltage, Breaker, and Wiring Requirements
Do not choose a heater based only on its size or wattage. The products here call for different electrical setups, including 120V and 240V supplies, dedicated breakers, and specific wire sizes. The listed requirements are not interchangeable. Have a qualified electrician review the exact model instructions and your apartment’s electrical capacity before you buy.
Get Permission Before Changing an Apartment
Hardwired heaters can require electrical and plumbing changes, and a rental agreement or building policy may limit those changes. Ask your landlord or property manager before purchasing equipment. Confirm who is responsible for permits, installation, maintenance, and restoring the apartment if the heater is later removed.
Measure the Installation Space and Plumbing
Measure the available wall or cabinet space, including room for water connections and service access. Compare those measurements with the heater’s stated dimensions. These products list 1/2-inch NPT water connections, but you should still verify that your plumbing layout is compatible and that the unit can be installed in a suitable location.
Compare Controls and Useful Protections
Digital displays and touch controls can make it easier to set a preferred temperature. Some models also list features such as overheat or dry-fire protection, while the Westinghouse adds app and voice controls. Treat these as conveniences and safety features, not substitutes for correct wiring, plumbing, and installation.
Think About Water Quality and Maintenance
Mineral buildup can affect water-heating equipment over time. Some of these products describe construction intended to reduce scale or corrosion, but that does not mean maintenance will never be needed. Check the manufacturer’s instructions for any water-quality limits, inspection steps, and maintenance guidance before installation.
Frequently Asked Questions
Can a point-of-use heater work in an apartment?
It can, if the unit fits the intended fixture, the building allows the installation, and the electrical and plumbing requirements can be met. Many of the models here require hardwiring, so permission and professional installation are important.
Will one of these heaters provide hot water to the whole apartment?
These products are described as point-of-use or single-water-point heaters. They are generally intended to serve a nearby sink or one other fixture, not several fixtures throughout an apartment at the same time.
Can I plug one into a regular outlet?
The models described here require hardwiring. Do not assume that a standard outlet is suitable. Follow the exact product instructions and have an electrician confirm the circuit requirements.
Is a 120V model always easier to install than a 240V model?
Not necessarily. The 120V models in this roundup still list high-amperage dedicated circuits and hardwired installation. A 240V model also needs a suitable circuit. An electrician should check what your apartment can support rather than relying on voltage alone.
How do I know what size heater I need?
Start with the fixture’s flow needs and the temperature rise you want. Compare those with the heater’s stated flow and temperature-rise figures, keeping in mind that incoming water temperature affects performance. Ask a plumber or electrician if the product information does not clearly match your use.
Does a tankless point-of-use heater give instant hot water?
It heats water on demand, but hot water still has to travel through the plumbing between the heater and the fixture. Installation distance and the plumbing layout can affect how quickly warm water reaches the tap.
Final Recommendation
For a typical apartment sink, the ThermoMate 3.5kW is the smallest option in this group, while the ThermoMate and CAMPLUX 4.5kW models offer another 120V choice with different stated electrical requirements. If you need more output and have access to 240V, the CAMPLUX 6kW may be worth considering. The Westinghouse 11kW offers the most listed output and smart controls, but its 60A circuit requirement makes it a much bigger project. Before choosing any model, get building approval and have a licensed electrician verify the exact installation requirements.
