Swimming Pool Filter Pressure

Dear John and all,

We are owners of a swimming pool for the first time and gradually learning about it.

When we set it going last Sunday, the filter pressure showed 0.9 bar which seemed fractionally on the low side to me. It has since fallen to 0.8 bar so I am getting concerned. We got in a pisciniste recommended by our neighbour when starting the pool and he was relaxed about the 0.9.

It was back-washed a few days ago. It is a 12x6 in-ground concrete pool. The cover to the bottom drain is detached due to corroded and broken screws. We have trees in the garden and pine needles are being blown into the water (and mainly floating) on the few occasions when we have a southerly wind rather than a mistrale.

Should we be concerned about the drop in pressure when as I understand it the pressure should be rising slightly as the filter clogs? Is a likely explanation dirt in the pipes? The pisciniste said that the main pump motor needed new (bearings or brushes - I assume but don't know exactly what he was saying) but it could wait to Autumn - as we have been running the pump a lot to clean the water might it have deteriorated to that extent so quickly?

Any thoughts greatly appreciated before we invite the pisciniste for his opinion.

Many thanks,


If the level in the pool doesn't drop don't worry about the drop in pressure.

Do you have air in the top of the pump?

0.9 is good

If the pump needs brushes etc change the pump it will be quicker and around the same price. If the bearings are tired the pump will use more elec to make it run. I suppose if they really are tired you will get a drop in pressure. Until you change the pump close the bottom drain half so it pulls more on the skimmers. Let me know what this does to your pressure.


Hi Mike,

Many thanks for your very helpful comments and suggestions; it is also reassuring. I'll to the test you suggest in the next couple of days.

Meantime it dawned on me that I had not checked the pump filter/basket - it was materially clogged with pine needles and at least I am back to 0.9 - and have learned another lesson.