Smart Earth Sprinklers

Sprinklers Turning on When It’s Raining?

Sprinklers Turning On When It's Raining

If your sprinklers still keep turning on when there is rain, there is no doubt a significant waste of water occurring. Luckily, this situation can be easy to fix, if you know what to look for.

As specialists in sprinkler maintenance, we here at Smart Earth Sprinklers know that the most common solution to this problem is the proper use of rain sensors. However, when a rain sensor fails to operate as it should, there is either a problem somewhere in the system preventing it from doing its job or the sensor itself needs to be repaired or replaced.

First off, let’s take a look at what rain sensors are, how they function, and what you need to do to ensure that your sprinkler system operates properly, especially during periods of rainfall.

What Is a Rain Sensor?

The primary function of a rain sensor is to stop your sprinkler system from irrigating the landscape when there is sufficient rainfall to water the lawn naturally.

Preventing sprinklers from turning on during periods of rainfall can help you not only conserve water but also prevent overwatering, which can cause root rot and fungal diseases in your plants. It can also help you reduce the amount of money you have to spend on water utilities by minimizing waste.

How Do Rain Sensors Work?

First, they need to be installed in open areas where they can enjoy direct exposure to the rain should it come down.

This means they should not be installed under trees, bushes, or any other kind of covering.

They should also not be installed anywhere where the sprinklers can wet them, as this will cause a feedback loop that causes the sprinklers to shut off as soon as they have turned on.

The most common kind of rain sensor contains small absorbent discs or grids that expand when they get wet. When the rain falls on the sensor and wets it, it expands until it triggers an electronic signal that is sent to the irrigation controller, instructing it to suspend watering operations. The sprinklers will then cease to operate until the sensor dries out.

Another type of rain sensor uses infrared technology. These send out a beam of infrared light that bends or refracts in the presence of water droplets. When the beam undergoes refraction, a signal is sent to the controller indicating the presence of water and so the sensor is shut off.

There are also rain sensors that activate the shut-off command after a small water collection trough triggers a weight sensor, allowing the sprinklers to turn on only when enough water has evaporated from the trough to release the weight.

How To Program a Smart Home Rain Sensor

Advances in technology have made it possible to integrate modern sprinkler systems with smart home setups, which include integration with advanced rain sensors. These sensors can be programmed and controlled remotely through smartphone apps or smart home hubs.

There are also less advanced rain sensors, which can be either programmed from the control box in your home or simply by manually adjusting the sensitivity settings on the sensor itself.

Why Do My Sprinklers Keep Turning on when it’s Raining if I have a Rain Sensor?

If you have a sprinkler system with a rain sensor installed and yet it continues to operate during rainfall, then there could be several factors at play that are causing it to malfunction.

One of the most common issues is a malfunction in the rain sensor itself, which most likely needs a wholesale replacement.

In some cases, the rain sensor is simply poorly calibrated, which means that it just needs a bit of tweaking for it to start working the way it’s supposed to.

In other cases, the sensor could be blocked by debris or improperly positioned under some kind of cover, which prevents it from accurately detecting rainfall. Simply moving the sensor to a more ideal position and/or cleaning it of debris could cause it to function the way it’s supposed to.

Other issues could also be to blame for a malfunctioning rain sensor, such as damaged wiring or connectivity issues between the sensor and the irrigation controller. This is particularly common with wireless electronic rain sensors. These issues could cause functional disruptions.

If your sprinklers keep turning on despite heavy rain, then all of these aspects should be investigated before resorting to replacing the sensor.

If your rain sensor is giving you trouble, then contact us at Smart Earth Sprinklers today. We have the necessary experience and expertise to carry out top-quality sprinkler maintenance services that will ensure your irrigation system is operating at its peak. We also offer maintenance plans that allow your system to have preventive service in order to avoid repairs, or replacements. Give us a call to find out more! Call (512) 694-1147.

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Smart Earth Sprinklers

Austin’s Most Reliable, Experienced Sprinkler Irrigation Repair Specialist