Pool Pumps

What are pool filtration pumps?

The filtration pump of a pool is essential to keep the water clean. We can say that the pump is the heart and the filter is the lungs. Mechanisms that must work together to keep the water free of algae and bacteria.

Pool filtration pumps are responsible for moving the water through the filtration system. Water is drawn in through the skimmers, suction inlet of the pool cleaner, and the drain, towards the filter. The filter (sand, cartridge, diatomaceous earth, etc.) will then retain all impurities to return clean water to the pool through the return nozzles.

If we look at pool pumps, we can see they have 3 distinct parts.

On one hand, there is the pre-filter. This part is located at the front of the filtration pump. It is where the water enters and where larger dirt such as branches or leaves is blocked. Its mission is to retain elements that, due to their size and volume, could damage the internal parts of the pump.

Continuing to observe pool pumps, we find the pump body. This body consists of a system of impellers that facilitate the movement of water. Finally, we find the heart itself, the pump motor. This part drives the pump impeller and allows water circulation.

The motor will make the central part of the pump work by injecting water into the filtration system before allowing it to return to the pool again through the return nozzles.

How to choose a pump for my pool?

We can choose a pool pump depending on many factors. Let's look at a few.

Based on the filter we have

One of the factors that will determine the choice of pump is the filter capacity. Buying a much more powerful pump could be a mistake. We must keep in mind that each filter has a limited capacity. This means that if we buy a pump that moves more water than the filter can handle, we could face problems with grooves or channels inside the filter that will allow water to return to the pool unfiltered. Also, the water could pass too quickly through the filter, which is also not advisable. In other words, a more powerful pump will not be efficient.

Be careful, as choosing a pump with less power than the filter requires will also not result in good performance. Therefore, the pool pump should always be adapted to the pool size so it can move the water correctly without damaging the filter. If we want to install a more powerful pump, we should replace the filter with one that has a higher capacity.

Guide for selecting the power of a pool pump

Based on the pool characteristics

The characteristics of the pool will also influence the type of pool pump we choose. To start with, the total volume must be filtered within about 6 hours. The calculation is simple, as we just need to divide the total volume of the pool by 6 to know the useful flow rate of the pump to install.

Another aspect related to the pool is: the length of the pipes, the distance between the pool itself and the technical room. The water will operate in a closed circuit back and forth. The greater the distance, the higher the power must be.

Also, the pipes must always have a sufficient diameter to allow water to flow smoothly. As a general rule, an above-ground pool has pipes of Ø 38. A traditional pool will have pipes of Ø 50. Also, for a pool with a volume of 100 m³, pipes of Ø 63 should be used.

Besides placing the pump near the pool basin, it is advisable to position it below the water level to avoid possible motor damage due to overexertion.

Pool filtration also influences; some pumps are not compatible with certain filtration systems. We must always check if the filter we have is compatible with the pump we want to install.

Also, it should be noted that some pumps are not compatible with certain water treatments such as salt or PHMB. For example, if the pump's pre-filter is made of polycarbonate, PHMB treatment is not recommended.

Based on price

We cannot deny that price will also determine our choice. Within the world of pool pumps, there is a wide range of different prices that will depend greatly on the following characteristics:

Pump power and flow rate.

Single-phase or three-phase pump.

Pump with one, two, or three speeds.

Pump with a recognised brand.

What types of filtration pumps are available on the market?

On the market, we can find a wide variety of pool filtration pumps.

Let's look at some common features and differences among most models.

Common features among pumps

Among the common features of filtration pumps is power. This data can be found in HP or KW with the following equivalences:

1 kW = 1.34 HP

1 HP = 0.74 kW

A small power is 0.35 HP. This power does not allow the use of hydraulic robots; for that, we would need a pump with a power of ¾ HP or higher.

They also share the flow rate. Flow rate refers to the amount of water the pump can absorb or filter per hour. Remember that all the pool water must be filtered within 6 hours at most.

Another common element is the pre-filter, which will be more or less voluminous. This pre-filter is responsible for retaining larger debris to avoid damaging the pump. Additionally, pumps have a high flow rate for low pressure.

Different types of filtration pumps

Not all pumps are the same. We can classify them according to these two aspects: connection and operation.

Types of pumps by electrical connection

According to the connection, we find single-phase or three-phase pumps. Depending on the electrical installation of our home, we will have to choose one or the other.

Types of pumps by operation

In this case, we can classify pumps as: centrifugal or self-priming.

Centrifugal pumps have a simpler system. We can say that the pump moves water from point A (suction point) to point B (pressure nozzles) thanks to centrifugal force.

1 - The movement of these pool pumps is possible thanks to the impeller or propeller located in the pump body.

2 - The rotation effect causes the wheel to push the water pumped by suction.

3 - Then, by acceleration, the water has no choice but to exit again.

In these cases, the pressure difference between the inlet and outlet will determine the flow rate. These types of pumps are smaller and very easy to install. Also, they are the most recommended if we have small technical rooms or underground rooms. They are the most economical and not too noisy. However, the flow rate of these pumps is lower than that of a self-priming pump, so if we need more, we will have to opt for the latter. Self-priming pumps are the most common nowadays. They operate similarly to centrifugal pumps. However, in these models, the operation is automatic; they start working upon detecting water arrival (after filling the pre-filter). We can say these are larger pumps. Regarding noise, they will be more or less noisy depending on the price. The more expensive pumps tend to be quieter. This price will also be affected, as usual, by the pump power, with the most powerful being the most expensive.

How to interpret a pump performance curve?

How to prime a pool pump?

How much does a pool pump consume?