The pump sucks water from the skimmer box at the pool and pushes it through the filter and chlorinator then back to the pool. The pump is sized to pump all the water in your pool through the filter in approximately 4 – 8 hrs, so the bigger the pool and filter, the more powerful the pump. The majority of home pools are roughly 50,000 ltrs and will have a 1hp pump.
The running time of the pump is usually split into 2 segments, 2-4 hrs in winter and 6-8 hrs in summer.
Inside the pump is a basket which prevents leaves and debris from going to the pump impeller. The pump basket should be checked regularly and emptied as necessary. There is an o-ring in the lid of the pump and it is worth lubricating this regularly. Do not use Vaseline. You can get a silicone grease from your local pool shop. If the o-ring is not maintained you can get air leaks around the lid.
Whenever you backwash your filter, with the pump running, run you finger under the base of the centre join of the pump to check for leaks. If it starts to leak through here, you need to get the mechanical seal inside replaced. This seal protects the pump bearings from water.