Causes of High Summer Utility Bills
- Hot water leaks. It may be hard to determine if faucet leaks are hot or cold. Here's a common situation: The water heater is located at one end of the house and there's a leaky tub faucet at the far end of the house. The leaking water feels cold. Interestingly, even though the water feels cool, it could be hot water that cooled as it flowed through the lengthy piping system. Here are a few tests in order of ease:
- Tighten the hot side handle and see if the leak diminishes.
- Put a screwdriver tip to the hot water pipe where it exits the water heater and press the handle end against your ear; the sound of running (hot) water is magnified.
- Feel the cold water supply pipe where it enters the water heater; if no hot water has been used in the previous half hour, the cold pipe should feel warm. (Heat from the water heater conducts to that pipe and warms it). If the cold-water pipe is cold where it approaches the water heater, and you ran no hot water recently, there may be a hot water leak. That pipe would be cold because cold water is entering the tank (and cooling the inlet pipe) to make up for hot water being lost to a leak.
- The water heater's thermostat malfunctions, the tank overheats, tank pressure builds and the pressure-and-temperature relief valve opens to release a flood of very hot water. It could be under the house, where no one sees it. In one case, the pressure / temperature relief pipe was sending scalding water from the under-the-counter water heater to a connection with the drain pipe beneath the kitchen sink. A steamy hot mist was rising from the sink drain hole; the electric usage had recently doubled. In many cases, the pressure-and-temperature valve simply fails, for unknown reasons. When the valve fails, hot water flows from the water heater 24 hours / day, leading to high electric, water and sewer costs. In most single family detached homes, the pressure / temperature relief line from the water heater emerges as a little down-spout low on the back side of the house or garage. If you find hot water plunging from that spout, call a plumber.
- The cats always nap on a particular spot in the middle of the kitchen floor. This typically happens when a hot water leak under the slab warms that spot. Repairs can be costly and usually involve major excavation to reach the broken pipe.
- The customer has a so-called "combination appliance" that uses a powerful gas water heater to heat the residence, as well as the water, in winter. During the summer the combination appliance keeps on sending heat to the house. This happens as a result of faulty valves, good valves installed incorrectly or faulty electronic controls. Summertime electric and gas costs both increase; and the electric air conditioning (cooling) cost typically doubles. Higher than expected summer gas cost is often a telling clue.
- The small pump on a water heating waste-heat-recovery unit runs nonstop. It happens whether the air conditioner is running or not and can become very costly, especially if the water heater is a long way from the air conditioner's outdoor condenser.
- The water heater thermostats are set too high. Each 10 degrees downward adjustment cuts water heating energy consumption by 3 to 5 percent. We recommend setting the thermostat(s) at 115 - 120F. If you have an electric water heater, set both thermostats to the same temperature. If you use a dishwasher that has no booster heater, set your water heater thermostats at 140F. If your dishwater heats its own water, you can lower your two water heater thermostats to 120F or less.
Water heater's lower element burned out. Electric water heaters typically have two heating elements: upper and lower. The lower element works longest, and tends to fail first. The result: Only the top 1/3 of the tank is heated. The water is just as hot as it was before, but it quickly runs out. If left that way, operating costs actually go down. But if the upper element's thermostat is dialed to a much higher temperature to compensate, operating costs go up.
- There's hot water in the toilet: six words that mean trouble. Rare. Call a plumber.
- Plumbing / pumping reversed on a large solar water heating system. Water heated electrically in 80-gallon basement storage tanks, then pumped backwards through the system to cool at the rooftop, and returned to reheat in basement tanks with continual circulation. This is extremely costly.