Water Heaters - Inspection and Operation

Author: Pacific Northwest Inspections Group, LLC   Date: 28-Apr-2014.   Category: Plumbing   Add to Favorites  Did you know that a water heater can become an explosive device without proper maintenance!

Water heaters should always be readily accessible so that gas and water can be shut off easily in the event of an emergency.
Thermostat settings are never changed at the time of the inspection, even when apparently set too high. Gas and water shutoff valves are not tested, and electric circuit breakers are not turned on (click here for helpful information concerning shutoff valves and circuit breakers).

Water heaters constantly operating at higher temperatures than suggested by manufacturer can be expected to have a shorter life span, and excessively hot water can cause personal injury and death from scalding and burns, particularly for elderly and children. Recommend maintaining thermostat setting at manufacturer’s recommended setting, typically indicated on the control knob. If hot water production is not satisfactory, consult with a qualified plumbing professional. Lower temperatures will also help conserve energy and save money by lowering utility costs.
Tank Size and Recovery Rate
Have a large enough tank to supply hot water? What is your recovery rate?
Actual recovery rate stated or calculated may be higher or lower. (The recovery rate is the number of gallons that can be heated to 100°F in one hour.)
Water heaters typically come with plastic drains, which typically fail upon first use; if a plastic drain is installed, be prepared to buy a metal drain at the time the water heater is first drained for maintenance.
Did your inspection report mention a TPR Valve?
The temperature and pressure relief valve (TPR valve) is a safety device, and when it operates, it typically indicates a problem with the water heater, usually water temperature or water pressure that is too high and dangerous. When the drain pipe terminates at an exterior location, an unknown location, or a drain or sink, it is difficult to determine whether or not the TPR valve has operated since any water that has been discharged is not seen because it evaporated, was absorbed by the ground, or was drained away. Typical recommendation is to place a 5-gallon pail under the drain pipe termination point and monitor the pail regularly to detect whether or not water has been discharged. If you cannot monitor the drain pipe regularly, recommend annual maintenance by a qualified plumbing professional. For more information on TPRVs click here.

Drain pipes should not terminate in foundation crawl spaces since moisture can cause damage to structural and mechanical components in the crawl space. If Client suspects that a TPR valve has operated, a qualified plumber should be consulted immediately.

If your water heater becomes noisy, it typically means that there has been a build-up of sediment in the storage tank. This probably typically can be resolved by draining and refilling the water heater. Water heaters should not be drained to the storm sewers; rather, drain them to your public sewer system or use the water to water plants and vegetation around your home. Installing a water modification system will also help prevent future sediment build-up in the tank.
Water Temperature
So what should the temperature be on your water heater? Pacific Northwest Inspections Group recommends 135°F for these reasons:
Dust Mites! Dust Mites and Dust Mites!!!
Wash sheets and blankets once a week in very hot water (135°F or higher) to kill dust mites. Young kids should never be left alone in a bathtub or near faucets when hot water heaters are set to this degree since serious burns can occur. Hot water heater temperature should be set at a safe level (discuss this with your doctor), and only when washing bedding is this water temperature ideal. A safe alternative is to set water temperature lower at home and wash the child's bedding at a laundromat where hot water is set to 135°F. Also todays plumbing fixtures have mixing valves where at sinks and showers you can independently lower the temperature.

Jumper bonding typically is not present at the water heater. The water heater and metal water pipes typically serve as part of the continuous grounding of the electrical system. The hot and cold water supply pipes above the water heater should be connected by a properly- sized wire to continue to provide such electrical grounding in the event the water heater must be removed. Replacement of a water heater should always be done by qualified professionals.

Securing the Tank
In King County You must protect your water heater in case of an earthquake by placing seismic bracing on the tank. The bracing must be two 20-gauge sheet metal straps as pictured. your strapping does not look like straps shown then yours should be changed. One strap must be on the upper third of the tank and the other on the lower third of the tank. Approved seismic bracing kits for water heaters are available at many retail outlets and can cost as low as $12.00!!! So get it strapped!
Expansion tanks 
If your water is on a closed system (the water can flow into your building but not out), an expansion tank or other approved thermal expansion device must be installed on your water system. The expansion tank is to hold water that can't be held in the water heater after it expands when it gets hot. If there were no expansion tank, the hot water would be released through the pressure relief valve. Is the tank required?
The Uniform Plumbing Code states that expansion tanks are required on any closed potable water system that has a water heater with a storage capacity of more than 3 gallons connected to it. A closed system means a water system that allows water to only flow in and not back out. For example, many of Seattle and Bellevue city water meters allow water to flow both in and back out. In other cities, such as Kirkland and Redmond the water meters may allow water to only flow in. If the water meter connected to a house allows water to flow both ways, then a thermal expansion tank is not required. There is an exception to this, is if there is a pressure reducing valve installed on the main water line coming into the house. If there is a pressure reducing valve on the main line, then it is a closed system and  expansion tank is required. There are also some municipalities that require thermal expansion tanks even though their meters flow both ways. They make this requirement because the city may have plans to install one-way water meters in the future and they want to make sure everyone is properly prepared for it and it is for this reason we will call it out on all of our inspections. It just makes sense and the tank itself only cost around $24.00 plus install. There are some pressure reducing valves that have a bypass feature which allows water to flow backwards once the pressure reaches a certain amount. Some plumbers feel this is an adequate substitution for a thermal expansion tank. This is not true. The bypass is intended as a safety feature. It is not designed to be used on a regular basis as a means of controlling thermal expansion on any hot water boiler system. 

Spacing Requirements
You must install your water heater in an accessible location. A minimum of 24-inch continuous width is required for access. You may put the water heater in the garage but you must protect it. Place a fixed barrier like a metal post in the cement between the water heater and where your car would park.
There are additional requirements for gas water heaters. If a gas water heater does not get enough combustion air the flame cannot burn to heat the water. If inadequate venting is installed, dangerous carbon monoxide gas can build up causing illness and even death. It is prohibited for a gas water heater other than those as "direct vent type" to be installed in a bedroom or bathroom unless meeting special criteria. Check for current local code requirements. To have a gas water heater, you will need a supply of gas. If you are going to install gas piping or change the gas piping you already have, a separate gas-piping permit must be obtained. The gas piping must not block the removal of the tank. Always adhere to the manufacturer’s installation instructions.
Now for Water Heater temperature.Water Heater Temperature 


To help prevent bacteria growth and to lower the risk of scalding, have a plumber install a tempering valve and crank up the temperature at your water heater to about 135 – 140F as ASSE recommends. These valves would be a good thing to install in every home. A tempering valve allows you to keep the water at a dangerously high, Legionellae-killing-temperature inside the water heater tank, yet it mixes cold water in with the hot water right at the outlet, making it so you don’t get this hot water at the rest of the fixtures in your home. The State of Washington Home Inspection WAC 308-408C-100 ask that we report generally accepted safe water temperature is 120F one hundred twenty degrees Fahrenheit.

Learn more about hot water heater setting and Dust Mites.


Water Heater Flush is it needed?


Most manufacturers recommend flushing your water heater at least once per year. 

The need for flushing depends on water quality and region. Seattle because it has some of the cleanest water in the nation, water heaters need flushed less often, but heaters in areas even 50 miles to the east need to be flushed every year. The harder the water, the more likely you’ll need a more frequent flush. Overall, it’s a good idea to stick to the manufacturer’s recommendations unless your trusted service provider says otherwise.





Proper Venting for Gas Appliances