Instant Hot Water Dispenser System: Should you install one?

By definition, an instant hot water dispenser system refers to a system or appliance which instantly delivers hot water at the point of use. The water temperature coming from a hot water dispenser is around 201 °F or close to the boiling point. But there is much confusion on what it means to have an instant hot water dispenser system. To better understand and differentiate the different ways you can get instant hot water via your tap, here are the three types of instant hot water systems commonly interchanged and confused from one another.

1. Whole-house instant hot water system. A whole-house instant water heating system is what you typically find in homes today. Water circulating through pipes goes through the water heater for heating and recirculation. The consistent movement of water from the heater to the pipes keep it in the desired temperature before it reaches the point of use. If you want greater efficiency in producing more supply of hot water, you can add small point-of-use heaters where there a high demand for hot water, for example in kitchen sinks and showers.

2. Tankless water heater. This type of water heating system is also called an on-demand water heater which heats water on demand and delivers it through the pipes and on to the point of use. It is important to distinguish the difference between an instant hot water dispenser system and on-demand water heaters because while tankless water heaters do heat water almost instantly, the delivery can take several seconds. Therefore, a tankless water heater is not synonymous with an instant hot water dispenser system.

3. Instant hot water dispenser. A real instant hot water dispenser provides water at near-boiling temperatures using an auxiliary faucet near the sink. The primary purpose of an instant hot water dispenser is to provide hot water for food and beverages. The mechanism consists of a small storage tank and an electric heater stored under the sink.

The main focus of this article is the instant hot water dispenser system. We will discuss further the many benefits of having an instant hot water dispenser in your home.

What are the benefits of instant hot water?

Most homeowners would love to have an instant hot water dispenser system in the kitchen. We use hot water for a number of things such as preparing beverages in the morning. If you have a hot water dispenser, you won’t have to wait for the water to boil in a kettle. Your hot beverage is ready for you to enjoy in no time. With a hot water dispenser, you can also appreciate the following additional benefits:

• Instant hot water dispensers use less energy than ordinary kettles.
• If you have a busy lifestyle, you will enjoy the convenience of hot water on demand straight from the tap.
• Instant hot water dispensers look sleek and will fit any kitchen design.
• It is easy to use even for individuals with disabilities.

An instant hot water dispenser system can come in a variety of designs and styles. While the most common set-up is to place the spout adjacent to the faucet on the sink, you can also have an instant hot water dispenser wall-mounted. Moreover, you can also reduce problems with limescale by adding filters to soften hard water.

Instant hot water dispenser DIY installation

An instant hot water dispenser system looks like a small electric hot water tank. The tank stores hot water dispersed through the connecting tap installed at the sink. The heater collects water through a small pipe running from the sink’s main water line. Hot water stays on top of the holding tank while cold water fed through the pipe stays at the bottom to be heated as needed.

Most instant hot water dispensers have capacities that range from 1/3 to a half gallon. The heating element used for each device can be anywhere from 500 watts to 1,500 watts. For example, if you have a half gallon hot water tank that uses 750 watts of electricity, you can produce up to 60 cups of instant hot water per hour. Since water delivered is at a near boiling point, water rate delivery is a lot slower than an ordinary hot water tank.

Most instant hot water dispensers come with a built-in thermostat so that you can adjust the water temperature. There are models which also come part of a whole-house water system, while there are manufacturers that produce models with built-in filters and water chilling option.

In most cases, homeowners choose to install an instant hot water dispenser system when they remodel their kitchens. But you can retrofit your sink with an instant hot water dispenser if there is enough space under the cabinet. If there is no existing hole on the sink to accommodate the faucet, you’ll need to drill a hole for the spout.

To install an instant hot water dispenser, you begin by mounting the water tank vertically underneath the sink. Next, you position the new spout on the sink with the corresponding water line connected to the tank. Then, you need to connect the dispenser to the main water line using a saddle valve and a quarter-inch pipe connected to the bottom of the water tank. To power, the dispenser simply plugs it into a power outlet under the sink.

Instant hot water dispensers are not expensive. For a standard model, expect to pay around $150 to $350. But the cost may go up depending on the features of the dispenser.

What is a plumbed in instant system?

If you don’t want a hot water dispenser with a built-in tank, you can choose a plumbed in instant hot water dispenser instead. What this means essentially is that the fixture is connected to the main water line. A plumbed-in instant hot water dispenser is a common fixture found in offices where there is a high demand for hot water used in preparing beverages. A hot water dispenser connected directly to the main water line can have its own filtration system to ensure that water coming out of the tap is fresh and clean.

For homes, on the other hand, instant hot water dispensers connected to the mainline can be quite convenient especially if you don’t want an additional water spout on your sink. This option comes at a higher price primarily because of installation and servicing. Some sophisticated plumbed in hot water systems include hot, cold, and even boiling water options.

What is a tankless instant hot water system?

Instant hot water dispensers used in kitchen sinks are quite different from a tankless instant hot water dispenser. It is a small point-of-use water heater that can supply enough hot water to a water fixture such as a bathroom sink. It works by heating water flowing through the device, similar to the working principle of a whole-house instantaneous water heater system. The device itself is compact and does not include a bulky storage tank. For the system to work, there is a separate connection to the water supply and another connection brings hot water directly to the faucet.

Since these units are compact, you can store the heater directly underneath the sink. These units also help save water as well as electricity. If you live in a large house with a high demand for hot water at different points of use, you will benefit from a tankless instant hot water dispenser system where you don’t have to wait long for hot water to reach the sink.


Whichever type of instant hot water dispenser system you prefer for your home, the first consideration is whether installing one will require significant modification on your kitchen or bathroom fixtures. You also need to make sure that your home has the required electrical outlets and fixtures to accommodate a hot water dispenser. An instant hot water dispenser system is certainly an excellent addition to any home because it makes a number of tasks more convenient and adds another level of comfort. Contact us at Fischer Heating & Air for more information!