Using Skimmer Weir Doors: What They Are and How They Work
Small accessories can make significant enhancements to your swimming pool. Some items you may not even realize if you have it or not.
A weir door for your pool skimmer is one of those accessories. They help control water flow and prevent debris from re-entering the pool. Without one, larger debris might miss the skimmer’s mouth.
While these doors are optional, let’s further understand their benefits and how to install them to your skimmer.
What is a Weir?
The definition of a weir is a “low dam built across a river to raise the level of water … or regulate its flow”. They are used in control water flows in lakes, ponds, reservoirs, and other bodies of water.
For swimming pools, it acts in the same way. A weir acts as a dam, or barrier, that controls water flow and raises or lowers (floats) depending on the water level in the pool. The main goal for a weir door is to better catch surface debris and keep it inside the skimmer
When talking about weirs, you may hear them be called “skimmer weirs”, “weir doors”, “pool weirs”, or something similar. Just know that they all have the same meaning!
How Does a Weir Door Work for Skimmers?
A skimmer’s main job is to draw water into the pool pump and filtration system to get it cleaned, filtered, and returned to the pool.
With a weir door attached to the skimmer, the amount of water that gets pulled in is limited to the surface. This makes it much easier for floating debris like leaves, twigs, and other contaminents to get into the skimmer.
Without a door, most of the water gets drawn from beneath the surface, leaving most surface debris in the pool.
Simply put, these doors force the water entering the skimmer to be from the surface, regardless of the overall water level.
If the pump needs to be turned off for whatever reason, the weir door essentially blocks debris from floating out of the skimmer body and back into the pool.
Choosing and Installing the Right Weir For Your Skimmer
For the most part, installing a weir door is very simple and should only take a few minutes.
You might need to do some investigating to figure out what size weir you need. The easiest and most effective way to find your size is by looking up your skimmer’s make and model. A simple google search should give you the correct size you need, either from the skimmer manufacturer themself or an aftermarket model.
If you do not know your skimmer model, you can measure the width and height of the skimmer’s mouth, or the rectangular box area where the water enters from your pool. Searching for a door with those measurements should give you a suitable door.
There are spring-loaded doors you can buy that will attach to the skimmer wall if there are no tabs or areas to insert.
Installing weir doors are easy and take a few minutes:
- Turn off the pump and filter. With no water movement, this makes it easier to move around the skimmer.
- Remove the skimmer lid. We want to install the door by reaching into the skimmer from the top.
- Most skimmers have two tabs or little holes located on the walls for a weir door. The doors themselves have lock pins or tabs that go into those holes. If this is the case, insert the door from the skimmer opening and insert the door’s tabs into each hole in the wall. If it is correctly inserted, the door should be “floating” to the surface of the water.
- If you are using a spring-loaded weir, insert the door then release the pins so that they stick on the walls. You may need to reposition it if it is too high or too low on the wall.
- Turn the pump and filter back on
Weir Happy You Are Using These Doors!
To be clear, weirs are totally optional and not necessary for any pool. However, they are small investments that can have a big impact on the overall cleanliness of the water.
You will be shocked at how well the surface of the pool stays clean with the doors installed compared to without!