What is instant hot water under kitchen sink?

Having an instant hot water tap under the kitchen sink provides convenient access to boiling water right where you need it most. Instead of waiting for water to boil on the stove, you can get instant boiling water for making coffee or tea, cooking pasta, blanching vegetables, and more. There are several options for installing an instant hot water tap, from simple under-sink systems to more advanced whole-house setups.

How Does an Under Sink Hot Water Dispenser Work?

An under-sink instant hot water dispenser connects directly to the cold water supply line under your sink. It heats the water internally and dispenses it from a separate tap mounted on your sink or countertop. Here is a quick overview of how most under-sink hot water systems work:

• A cold water line connects to the hot water dispenser.
• Inside the dispenser, a coil or heating element heats the water to a preset temperature, usually around 200°F.
• Insulated hot water lines run from the dispenser to the dispensing faucet.
• When you turn on the tap, a flow detector sends a signal to the heater to heat the water.
• The now hot water flows through the faucet. Many systems dispense water in a concentrated stream for faster heating.
• A temperature sensor and limiter prevent the water from overheating.

The main components of an under-sink hot water system are the heating tank, faucet, and connecting pipes/hoses. The system taps into your existing cold water line for its water supply. An electrical connection provides power for the built-in heating element.

Types of Under Sink Hot Water Heaters

There are two main types of heaters used in instant hot water dispenser systems:

Tankless Coil Heater

This type of heater uses an internal coil that heats the water as it flows through. Tankless coil heaters provide hot water on demand without storing any water internally.

Hot Water Tank

Some under-sink systems use a small hot water tank, usually around 1/2 gallon or less. The tank continually heats a small reservoir of water to the preset temperature. When you turn on the tap, hot water is immediately dispensed from the tank.

Tankless coil heaters have a faster water heating response time, while small tank models provide a ready reserve of hot water. Both designs can deliver an endless supply of hot water on demand.

Benefits of Instant Hot Water Under the Sink

Having an instant hot water dispenser provides several advantages over heating water on the stove or in a microwave:

• Convenience: Hot water is always ready and waiting with the push of a button or turn of a tap.
• Time savings: No more waiting for a kettle or pot of water to boil. Hot water is available instantly.
• Energy efficiency: Heats water only on demand so there are no standby losses. More efficient than running the stove or microwave.
• Precise temperatures: Dispenses water at optimal temperature for drinks or cooking.
• Safety: Reduces the risk of burns from handling hot kettles or pots.
• Compact size: Installs under the sink to save counter space in the kitchen.

Whether you’re a coffee drinker, avid home chef, or live in an older home with small taps, an under-sink hot water tap can make your time in the kitchen more enjoyable and productive. The convenience is hard to overstate.

Cost of Instant Hot Water Systems

The cost of an under-sink hot water system includes the purchase price of the unit itself plus installation. Expect to pay:

• Under-sink system unit: $200 – $400
• Electrician installation: $200 – $500
• Plumber installation: $100 – $250
• Total cost: $500 – $1200

More advanced instant hot water dispensers for larger homes cost $800 – $1500 installed.

Ongoing costs include electricity to run the heater and replacing filters every 6-12 months. Overall operating costs run $20 – $60 per year depending on usage.

Installation of Under Sink Hot Water Heaters

Installing an under-sink hot water dispenser involves both plumbing and electrical work. Proper installation is critical to ensure safe operation and compliance with local codes. Here are the basic installation steps:

1. Turn off water supply: Shut off the cold water line under the sink and open the faucet to depressurize.
2. Install tee fitting: Cut into the cold water line and install a tee fitting to branch off water supply to the hot water heater.
3. Connect water lines: Connect insulated hot and cold flexible water lines from the heater unit to the dispenser faucet.
4. Mount faucet: Drill holes in the sink or countertop to mount the dispensing faucet.
5. Connect power supply: Plug in the unit’s power cord or hardwire to a dedicated circuit.
6. Program unit: Set the temperature and activate safety features.
7. Check for leaks: Turn on water and inspect all connections for leaks.

Most manufacturers recommend having a professional plumber and electrician install the system. This ensures proper installation and compliance with plumbing and electrical codes. Trying to DIY the installation could void warranties.

Maintenance involves replacing filters anddescaling the heater elements annually. Always check for leaks and damage that could impact safety.

Choosing the Best Under Sink Hot Water Heater

Consider the following features when selecting an under-sink instant hot water system:

• Heating technology – Tankless coil or tank models each have pros and cons.
• Temperature settings – Look for precise temperature controls.
• Flow rate – Faster flow reduces waiting time for hot water.
• Energy efficiency – Insulated tanks prevent standby heat loss.
• Safety certifications – Choose units tested for safety compliance.
• Warranty – Units with longer warranties suggest better reliability.
• Filter – Replaceable filters protect from scale buildup.

Shop for an under-sink hot water heater from reputable plumbing brands like InSinkErator, Kohler, Franke, and Ariston. Talk to a plumber about which type and size of heater will work best for your home.

Pros and Cons of Under Sink Hot Water Heaters

Here is a quick look at the key pros and cons to consider about under-sink hot water dispensers:

Pros:

• Provides instant boiling water on demand
• More convenient than stove or microwave
• Heats water only as needed, no standby energy waste
• Frees up counter space by eliminating kettle
• Safer than handling pots of boiling water
• Many size options for small to large households

Cons:

• Installation requires plumbing and electrical work
• Upfront cost is higher than buying a kettle or pots
• Ongoing filter replacement and descaling required
• Possibility of leaks if not properly installed
• Takes up some under-sink space

For most homes, the convenience and safety of having instant boiling water on tap outweighs the upfront costs and installation work required. But carefully consider your needs.

Whole House vs Under Sink Hot Water Dispenser

Along with under-sink units, whole house instant hot water systems are also available:

Whole House Systems

• Designed for larger homes
• Central tank or tankless heaters connect to home plumbing
• Delivers hot water to all sinks, showers, appliances
• More expensive professional installation
• Higher equipment and running costs

Under Sink Systems

• Compact size for single sink usage
• Simple DIY or pro installation
• Lower upfront and operating costs
• Provides hot water only at one tap
• Limited hot water flow rate

For a kitchen island or primary kitchen sink where you need a dedicated supply of instant hot water, an under-sink system is the most practical choice. Whole house systems make more sense for larger homes where hot water is needed at multiple taps.

Instant Hot vs Hot Water Dispenser vs Kettle

How does an under-sink instant hot water system compare to dispensers and electric kettles?

	Instant Hot Water Under Sink	Hot Water Dispenser	Electric Kettle
Setup	Permanent install under sink	Countertop appliance	Countertop appliance
Hot Water Capacity	Unlimited on demand	~1 Liter reservoir	1.5-2 Liters
Convenience	Tap dispenses boiling water instantly	Press button to dispense hot water from reservoir	Heats water in batches when needed
Ideal For	Frequent small amounts of boiling water	Hot drinks, soups, oatmeal	Larger amounts for drinks, cooking
Cost	$500 – $1200 installed	$100 – $300	$25 – $150

Under-sink systems provide the fastest access to boiling water but have a higher upfront cost. Countertop dispensers or electric kettles can also be convenient options depending on your needs and budget.

Safety Tips for Under Sink Hot Water

To safely operate an under-sink hot water dispenser:

• Keep children away from the tap to prevent accidental scalding.
• Open the tap slowly to allow hot water to flow gently, not splatter.
• Never fill containers that could melt or ignite.
• Avoid touching the metal tap nozzle when dispensing.
• Inspect hoses regularly for leaks and damage.
• Install child safety devices that limit tap operation.
• Make sure electrical connections are properly grounded.
• Always turn off the main water supply before servicing.

Treat the boiling water from the tap with the same level of care as you would boiling water from a stove or kettle. Take precautions to prevent burns. Also ensure the system is properly maintained and serviced when required.

Conclusion

An instant hot water tap provides an efficient and convenient solution for accessing boiling water in the kitchen. While the installation cost is higher than other options, under-sink systems save time and counter space while delivering hot water safely on demand. For big tea drinkers, chefs, and busy families, the benefits are often well worth the investment. Proper installation and ongoing maintenance are key to ensuring optimal performance and safety. With the right under-sink hot water heater, you can streamline meal preparation and instantly elevate your kitchen’s functionality.