Water heater timer
Electric hot water heater timers
A hot water heater timer is worth considering. Timers are designed to reduce heat loss and improve the efficiency of an electric powered water heating storage tank. The cost associated with reheating stored domestic water when demand is either off peak or non existent can be reduced with an electric timer.
Electric powered tanks (including those in both heat pump water heating systems and in solar powered systems) can benefit from the addition of a timer.
There are several things for would be consumers to consider;
Gas Powered Storage Tanks and Timers
Many industry professionals share the conventional wisdom that timers are less effective when applied to gas powered storage tanks. In the past, water heater timers were available for residential gas powered storage tanks.
Most models were mounted directly to the gas valve. The timer was designed to electro mechanically close and open the gas valve. Many gas valves fitted on the tanks were not designed for multiple daily adjustments. In some cases gas leaks occurred due to the wear on the valve seals.
Currently (and in the foreseeable future) a hot water heater timer is not a viable option for a residential gas powered storage tank.
Some commercial gas powered storage tanks (as well as in apartment buildings) often have electric controls connected to the valve. Others have solenoid valves that electro mechanically control the gas valve.
In such applications, gas water heaters can be fitted with programmable timers. Consulting a local water heating professional for installation is recommended.
Programmable settings and heat loss
All conventional storage tanks experience standby heat loss because the heating element is designed to maintain the temperature of the stored domestic water. Maintaining a pre set temperature is a cycling (on and off) task that repeats itself. In many modern households this repetition can be both unnecessary and costly.
With a water heater timer the tanks' heating element maintains a set temperature only at pre determined times of the day.
Much like with programmable thermostats for home heating and cooling systems, water heater timers are designed to take advantage of the extended daily and/or weekly periods when demand is either low or non existent.
Timers and Off Peak Electricity Rates
Check with your local electricity provider and inquire about demand management programs. Demand management programs are designed to deal with as well as discourage high peak electricity use.
Providers that have such programs offer whats referred to as "time of use" rates where higher electricity rates are charged during on peak hours and lower rates are charged during off peak hours.
Programming or coordinating an electric hot water heater with a utilities off peak rate can significantly increase the timers' overall effectiveness.
Significant Savings With Timers?
With the addition of an electric water heater timer the U.S Department of Energy estimates a 5% to 12% reduction on water heating costs. The Illinois Institute of Technology has estimated up to a 26% reduction on water heating costs.
Several factors will ultimately determine the long term energy savings. The tanks' internal insulation or R-value rating as well as whether or not additional external insulation has been applied are very important factors.
The households' hot water consuming habits as well as the ability or inability to take advantage of time of day or off peak electricity rates can be more important in determining long term energy savings.
In general, timers are more effective when installed on less insulated (internally and externally) electric powered storage tanks and when there coordinated with utility off peak electricity rates.
Types of water heater timers
Water heater timers are available for both indoor and outdoor applications. Some models are designed for installation near the storage tank, other designs provide the additional flexibility of mounting the timer relatively far away from the tank.
Different types of timers have different features as well as varying programmable settings. It's important to note that differences in features as well as settings may determine which type (and even which model) is more suitable for your home.
Box water heater timers are classified by there appearance. These models have either digital electrical control components or mechanical switch components in an enclosed box. The box housing is usually made of plastic or light metal.
- Currently the most common type of timer available.
- Digital box timers generally have back up batteries in the event of a power outage, while models with mechanical switch controls do not.
- Models with mechanical switch controls use approximate time settings and digital box models offer more accurate programmable settings.
- Box timers are available for both indoor and outdoor installation.
- Generally designed for mounting near the storage tank.
- Are directly wired to storage tank and generally have fairly easy to follow directions for installation.
- Compatible with a wide range of voltage; from 120 volts to 270 volts.
Digital Programmable Timers
Digital timers offer more flexibility in the form of additional programmable settings. These models are better suited for households with varying consumption habits. The overall flexibility of scheduling that is provided will ultimately depend on the particular digital hot water heater timer.
- Quickly gaining popularity amongst energy savings minded homeowners.
- Can allow for different settings for different days of the week and weekend.
- Generally come with user friendly LED back light control screens as well as decorative mounting plates.
- Designed for indoor installation and far removed from the storage tank.
- These hot water heater timers are wall mounted, generally near the AC and furnace thermostat for additional access and home automation.
- Digital programmable timers are not wired directly to the tank. Additional electrical wiring is required. Consulting a local water heating professional for installation is highly recommended.
- Generally operate on 110 volts.
Countdown timers offer additional flexibility in scheduling when compared to most box models as well, but not when compared to programmable models. Countdown timers offer intervals for on demand hot water use that can be pre set. The timed intervals offered depend on the particular model.
- Seldom utilized with storage tank water heaters but quite compatible.
- Pre set intervals can range from 10 minutes to 60 minutes. For example a user can set a 20 minute period to activate the storage tank for machine washing. Some models have mechanical dials and others have digital dials.
- Come with decorative mounting plates much like programmable timers.
- Generally designed to be installed far away from the storage tank.
- Much like with programmable models, there designed for wall mounting and installation near the home heating and cooling thermostat if desired.
- Countdown timers are not wired directly to the storage tank. Consulting with a local water heating professional for installation is recommended.
- Generally operate on 110 volts.
More on energy efficient water heating
Water heater maintenance and efficiency
- Water Heater Maintenance; how to extend the life of an old or recently purchased storage tank.
- Water Heater Anode; periodically inspecting the sacrificial anode rod is a maintenance procedure that protects the storage tank from corrosion.
- Drain Hot Water Heater; draining or flushing the storage tank removes sediments that can compromise efficiency and volume.
- Water Heater Drain Valve; inspect the drain valve on the tank for potential leaks and drips.
- Water Heater Expansion Tank; high water pressure can compromise any storage tank. The addition of a hot water heater expansion tank can both resolve and prevent high water pressure.
Energy efficient water heating options