Home Improvement : Super-High-Efficiency Water Heaters Frugal

Question: My gas water heater is getting leaky and I want a high-efficiency model. What is the highest-efficiency gas water heater made and will it save much on my gas bill each month?

Answer: A water heater uses more energy than any other equipment in your home except your furnace and air conditioner. It typically accounts for 20% to 25% of your annual utility bills. Installing a new super-high-efficiency water heater can save more than $100 a year.

The new super-high-efficiency gas water heaters use a submerged chamber burner design. This means that the combustion of the gas takes place inside a special heat exchanger that is totally surrounded by water inside the water heater tank.

This greatly improves the heat transfer from the burner to the water in the tank so that less is lost up the flue. You can expect combustion efficiency in the super-high 85% range. The high efficiency provides fast recovery, so there is plenty of hot water for many showers in the morning.

The flue, which runs up through the center of the tank, is lined with baffles. These cause turbulence in the hot exhaust gases to transfer even more heat to the water before the gases are lost up the flue.

In contrast, a new standard-efficiency gas water heater has a standard open burner located beneath the water heater tank. That allows more heat loss and yields lower efficiency, about 60% to 70%.

There are other advantages of a submerged-chamber burner design. Since the burner is totally enclosed, it is much quieter when the burner is on. Also, you can set the water heater directly on the floor without any feet or against a wall (zero-clearance).

A submerged-chamber burner water heater costs about $100 more than a standard burner one. With the higher efficiency, the gas savings should pay back its initial higher cost in couple of years. Over its entire life, the savings can be many hundreds of dollars.

Whenever you select a new water heater, check the specifications for the amount of insulation in the tank walls. There can be considerable heat loss from the tank itself. The tanks with the highest insulation values, up to R-16, use foam insulation, not fiberglass. You can write to me for Utility Bills Update No. 9, showing a list of manufacturers of super-high-efficiency submerged-chamber burner water heaters, product information and specifications, and a chart showing the dollar savings. Please include $1 and a self-addressed envelope.

Q: Does the way we tilt the slats in our Venetian blinds affect the energy efficiency of our windows?

A: In the winter, the air between your window and Venetian blind is cooler and more dense than the surrounding room air. Therefore, it tends to drop. Adjust your blinds so the slats are angled, from the slat top to bottom, toward the window. This helps keep the cold air against the window and out of your room.

In the summer, the air near the window is warmer and less dense, so reverse the angle of the slats. As the warm air rises, it tends to stay between the window and the Venetian blind slats.

Q: Does it waste much electricity to put hot foods in the refrigerator immediately after we finish dinner or is it better to wait until they cool down a little?

A: From an energy-efficiency standpoint, any warm food you put in your refrigerator forces the compressor to run more. However, people often leave warm food out to cool too long and they run the risk of food poisoning. Check with your local health department for safe cooling time periods.

If you do put steaming hot foods into your refrigerator, put them in clear containers and cover them with a tight-fitting lids. This reduces the amount of water vapor inside the refrigerator and possible frost buildup in the freezer section. The clear containers allow you to see what food in each so you don’t have to hold the door open as long when selecting the foods the next day.

Q: We are remodeling our kitchen and we want to make it as energy efficient as possible. What is the best location for our new range and refrigerator?

A: The location of your range and refrigerator can impact the cost to operate them. Try to keep them separated at least two feet with a counter or cabinet in between them. Otherwise, your hot oven and your cold refrigerator battle each other and waste energy.

Your refrigerator needs adequate air circulation through the condenser coils to operate efficiently. You should locate it along an open wall, not back in a corner or near a hot air register. The best location for your range is away from breezes or windows. The air flow can literally blow the heat away from the burners or electric elements.

Letters and questions to Dulley, a Cincinnati-based engineering consultant, may be sent to James Dulley, Los Angeles Times, 6906 Royalgreen Drive, Cincinnati, Ohio, 45244.