Pompe di circolazione con un timer: sempre una scelta sbagliata

For the purposes of this article I will assume that you have a long wait for hot water at one or more fixture in your home and that you are researching the various options that include timers.

There are 2 styles:

1. On top of a water heater
2. Under a sink.

Please note that it is not recommended to use pumps with timers with tankless water heaters. Running a tankless heater for long periods of time will wear them out quickly and in most instances void their warranty.

Tank mounted pump with timer

Pumps mounted on top of the water heater run continuously when the timer is in the on position. A bridge valve is installed under the farthest sink. Bridge valves have a temperature sensor that will close the valve when the water reaches 95 degrees F. The pump continues to run even if water is not flowing.

Pros

• Instant hot water during the periods the timer is in the on position
• Easy to install

Cons

• Bridge valves wear out quickly because the pump is pushing against them when they are closed
• Energy is wasted because the water pipes are hot during the times when the timer is set in the on position. The pipes cool down and more hot water is required to take its place.

Note: The increased energy cost will be greater than the cost savings of no wasted water.

Under sink pumps with timer

Pumps installed under a sink with a timer are controlled by a timer and temperature sensor. During the periods the timer is set to on the pump will run until the water reaches a preset temperature. When the water cools down the pump will turn on again until the water reaches the preset temperature.

Pros

1. Unlike the tank mounted pumps the under sink pumps will shut off after the water reaches a certain temperature
2. Instant hot water during the periods the timer is in the on position

Cons

1. Difficult installation – requires an electrical outlet under the sink
2. Energy is wasted because the water pipes are hot during the times when the timer is set in the on position. The pipes cool down and more hot water is required to take its place.
3. Timers require you to pre-determine what time you will need hot water.

Note: The increased energy cost will be greater than the cost savings of no wasted water.

Conclusion:

Although the pumps with timers may seem to be the least expensive choice the extra energy costs incurred greatly offset the benefits.

I give pumps with timers 2 emphatic thumbs down.

Do Not Buy