A water chiller or an instant hot water dispenser provides a cold glass of water or a warm cup of tea or soup right when you need it. John Woodard, our Master Water Specialist, explains the difference between a water chiller and a water cooler and shares how to find the most efficient hot water dispenser. What is a water chiller? A water chiller is an electrical device that sits under your kitchen counter. It's able to provide chilled water through a special tap on your kitchen counter. It doesn't take up space in your refrigerator with a jar like a water distiller, and you don't have to wait for the water to get cold. How does a water chiller work? A water chiller uses sealed refrigeration just like a water cooler. A water cooler has a reservoir that it chills water in. However, an under-counter chiller doesn't have a big reservoir, but it's able to chill water at eight ounces per hour. What are the different types of water chillers? Water chillers all use sealed refrigeration, just like your refrigerator or water cooler. Chillers could differ in size or the amount of chilled water they provide in a given period of time. When you put a water chiller under the counter, you need to make sure it has plenty of ventilation because sealed refrigeration creates heat that comes out of the unit. Some water chillers have a place on top with a fan that heats up the underside of your kitchen cabinet. This changes the temperature of the ambient water feeding the water chiller. If we don't have adequate ventilation from the cabinet, the water going into the chiller heats up, which in turn, heats the water coming out of it. How do you install a water chiller? First, put an adapter on your cold water line that serves your regular faucet a to feed the water chiller. It has an IN and an OUT. The out delivers water to a special tap that you install on the kitchen countertop. Keep in mind that anytime the temperature of water changes, it expands or contract, so installing a chiller requires extra tubing and a little check valve to give the water a place to go while it's changing its shape, or expanding or contracting. A bypass, or an expansion kit, should be installed with your chiller. How do you maintain a water chiller? There's not much to it. Turn it on and run it. If you're feeding chlorinated city water through it, then there aren't any substances inside that could damage the chiller. A water chiller has a lifespan and a warranty. Chillers could last anywhere from one to ten years. Internal fittings might start to crack and fail, but chillers don't require much ongoing maintenance. What is an instant hot water dispenser? An instant hot water dispenser heats water up, so you can get a cup of hot water to make tea or soup with. The instant hot tank provides hot water through a special tap on top whenever you want it. How does an instant hot water dispenser work? The instant hot water dispenser works just like an electric water heater. There's a tank inside the water heater that contains a heating element. The heating element is thermostatically controlled, so it maintains the water temperature based on how you set the thermostat. You don't want the temperature so high that it boils, but you want it hot enough to be able to make food and beverages. How do you install a hot water dispenser? A hot water dispenser connects to the cold water supply that feeds your regular faucet. Use an adapter to run the water directly to the faucet. If you want to add a filter on the system, put it between the cold water supply and the faucet. Water flows directly to the faucet because the hot water dispenser creates steam, which in turn, creates pressure. These units use an open-vent faucet. That means that the hot water line comes from this tank through the faucet. The tubing goes all the way to the end of the tap gooseneck. There's no valve on the gooseneck, which allows the pressure that builds inside the hot tank and vent through the faucet. What happens when you open the faucet to get hot water? Water is diverted into the hot tank and pushes hot water out through the faucet. There may be a slight delay in dispensing water. An open-vent faucet never builds pressure in the hot tank under your sink. Too much pressure would result in failure. What is the best instant hot water dispenser? The best hot water dispenser would be easy to install and easy to use. With an open-vent hot water dispenser, you don't have the worry about expanding pressure or complicated installation. The Quick & Hot from Mountain Plumbing meets these criteria and is energy-efficient. Are instant hot taps energy-efficient? Instant hot water dispensers use energy. The heating element inside uses energy to heat the water. However, the heating element is thermostatically controlled, so it's only maintaining a temperature. It's not constantly heating, much like your home water heater. It uses energy to raise the temperature slightly to keep up with your thermostatic setting.