What Sort of Pool Sweep, Cleaner or Robot Should I Buy?

There are four types:

1. Pressure cleaners, which use a separate pump and a thin pressure hose to power the cleaner.
2. Robots, which use low voltage electricity for power and either a battery or a thin electric cord.
3. In-Floor cleaners with pop-up jets that sweep leaves to a special main drain. These have their own pumps
   and must be installed when the pool is being built.
4. Suction cleaners, which plug a large diameter vacuum hose into the skimmer box and uses the water flow of the pool filter pump to power the cleaner.

Pressure Cleaners

In our experience this is the best type of pool sweep for most pools for several reasons, including:

• good long-term unattended operation
• large leaf capacity
• easy to lift out of the pool
• easy to empty the leaf bag
• and largely trouble-free
• Improves water circulation

They do a good job of cleaning the pool and you can go away on holidays and leave them running.  They may fill up their waste bag but they will not be damaged and the pool will generally be in good shape when you get home.

The two main types are Polaris and Jet-Vac.  The Polaris climbs the walls and brushes them whereas the Jet-vac does not, however, the Jet-Vac will pick up larger leaves and hold more of them.  

You must have a suitable fitting in the side of your pool, usually opposite the skimmer box, to use a Pressure Cleaner.  This is plumbed to its own pump.  A complete cleaner, head, hose and pump will typically cost between $1,500 and $1,800 including GST.  If you don’t have a wall fitting and the wall is exposed and accessible from the outside, it is surprisingly easy and inexpensive to install one.

If you have a Pooled system, the pool sweep will be controlled automatically by the system and adjust for season and, in some cases, weather.

Robot Cleaners

Robot Cleaners are very effective but more fiddly than Pressure Cleaners and do not hold as many leaves and debris.  They are provided on a trolley and need to be removed from the pool after each use.  They are often heavy when full of water and need to be lifted out carefully to avoid strain while the water drains.  They need to be opened to empty the collected debris and this can be somewhat fiddly depending on the brand.  Some of them tangle their electric power cables and need untangling after each use.  They should also be stored out of sunlight as this affects the ABS plastic from which they are made.

If you get a quality robot, it will usually ‘learn’ the pool and do a good job of cleaning the pool, and the walls, while some types climb and clean stairs as well.  They filter quite finely and are the quickest of cleaners, taking two hours to do the average pool.  We prefer the larger, more durable commercial grade robots.  We have not tested the battery-powered versions as yet but urge some caution as the technology is new and unproven. We suggest you stay with the cord powered versions.  Most have a power supply on their trolleys.  This plugs into the mains and provides the low voltage for the robot.  They use only about 200 watts and are economical.

If you do not have a pressure cleaner fitting, try a robot.

In-Floor Cleaners

In-floor cleaners are built into the pool at the time of construction and have pop-up jets that are activated in sequence and use jets of water to sweep leaves to a special main drain that collects them.  Unfortunately, we see quite a few of these that have been installed incorrectly and either do a bad job of ‘sweeping’ or use a lot of energy doing so.  When they work, they work reasonably well but are generally the most energy intensive of all the cleaners as they need to run the longest times.

Suction-Side Cleaners

We do not recommend these for a range of reasons:

• They prevent you skimming the water surface in most cases. Virtually all the debris and dirt in a swimming pool comes through the surface. The surface layer is the most highly contaminated in the pool, and the one most essential to clean. The NSW Government Health Department recommends that 75%-80% of the water filtration in swimming pools be taken from the top layer, and the remainder from the main drain at the bottom of the pool. The World Health Organisation recommends 90% and 10% respectively.
• If you leave a suction cleaner plugged-into the skimmer box as most people do, you are taking no water from the surface layer at all. While the suction cleaner is busy cleaning the bottom of the pool, its suction hose is usually completely blocking the skimmer box and therefore the filter takes 100% of its water from the bottom.
• The surface layer of the pool will then become progressively more contaminated and, debris and dust that should have been skimmed, will now slowly sink to the bottom making the water dirty and cloudy on the way and the surface unpleasant. This all makes for much more work (and energy usage) for both the suction cleaner and the filter.  You are unlikely to achieve the higher water quality standards if you use a suction cleaner. Moreover, the water is unlikely to be as well sanitised.
• Suction cleaners are also not well suited to automatic operation. If you have one, it is likely that you have a lot of leaves in your pool and you will have to manually clean out the skimmer box quite often or else the efficiency of the filter will fall quickly due to the skimmer being blocked. Of course, all skimmer boxes need periodic cleaning, however any leaf load that accumulates is better distributed between a pressure-side cleaner and the skimmer, rather than being all in the skimmer.
• Suction cleaners tend to choke on larger debris and leaves and will not pick up such things as gum-nuts and small sticks, unlike pressure-side cleaners.
• Contrary to popular belief, suction cleaners do not run for free. In fact, they use a significant amount of filter pump energy. Filters using suction cleaners need to run at higher speeds or longer times, irrespective of the type of filter. US Electricity utility studies suggest that suction cleaners consume as much as three-quarters of the energy of pressure side cleaners which use their own separate pumps (and, in our opinion, do a better job in a shorter time).
• Some suction cleaners are noisy and not suitable for night time operation.
• Some suction cleaners have a plate in the skimmer box with an additional inlet to the suction hose.  This is sometimes spring-load and it has the intention of allowing some surface skimming.  This is seldom successful as it requires high pump power and water is diverted from both skimming and suction preventing either working well. More often however, it forms a vortex that sucks air into the pump, stopping it momentarily, till it primes itself again.  This puts pressure surges through the system and loses energy and filtration efficiency.
• Water circulation is impacted as the water suction is only through the head of the cleaner. Our experience is that pools with suction cleaners have poorer water quality and experience more stagnant areas and are at greater risk of algae infection.

The Pooled system can operate with existing suction cleaners, however we strongly recommend that you consider another type of cleaner, such as a pressure-side cleaner with its own pump, or a robot. We believe that you will get a much better result.