Pumps, filters and equipment
Looking after the pump lid and O-rings
A small rubber ring keeps air out of the pump. When it dries, flattens or cracks, the whole system suffers.
The pump lid O-ring seals the clear lid over the pump basket. Every time the basket is emptied the ring is disturbed, and in a hot plant room it dries and hardens. A dry, flattened or nicked O-ring lets air into the pump on the suction side, which shows up as air in the pump basket, bubbles at the return jets, noisy running and weaker flow.
Equipment guides cover servicing and faults on the plant an existing pool already has.
The unions either side of the pump have O-rings too, and lids themselves can crack from over-tightening or heat. Keeping these seals clean, lightly lubricated with a product suitable for pool O-rings, and replacing them when worn is one of the cheapest ways to protect the pump.
The short version
Heat dries O-rings
Hot plant rooms age rubber seals faster than people expect.
Use the right lubricant
Pool O-ring lubricants keep rubber supple; some petroleum products make it swell.
Check the lid itself
Hairline cracks in the clear lid let air in as surely as a worn ring.
Caring for the seals
Cleaning
Wiping the O-ring and its groove free of grit and hair each time the basket is emptied.
Lubricating
A thin film of suitable lubricant, not a thick coat that collects debris.
Replacing
Rings that are flattened, cracked, stretched or nicked are replaced with the correct size for the pump model.
Signs a seal is failing
Air pocket in the pump lid
The basket should be fully flooded while the pump runs.
The lid is hard to seal
Needing extra force to stop air usually means the ring is worn.
Visible cracks
In the ring, the lid or the union nuts.
Common questions
Can I use petroleum jelly on the O-ring?
Use a lubricant recommended for pool O-rings; some petroleum products can make rubber swell.
How often should O-rings be replaced?
When they are flattened, cracked or no longer seal — often sooner in very hot plant rooms.
Do the unions need attention too?
Yes. Union O-rings dry out the same way and are a common source of suction-side air.
Related pool care guides
- A robotic pool cleaner that is not working properlyA related check on the same part of the plant.
- A pool pump that has become noisyA related check on the same part of the plant.
- Backwashing a sand filterA routine task that prevents the same trouble.
- When pool pH is too highAnother water problem with a related cause.
This guide sits under pump & filter services. Browse all pool care guides. We look after pools at homes and commercial properties across Dubai.
Ask about your pool
Describe the pool and the question. We will answer directly, and say when the honest answer is that nothing needs doing.
Phone
+971 56 181 0106Talk through what the pool is doing and book a time for us to see it.
WhatsApp
Send a messageThe easiest way to send photographs of the pool and plant room.
Next step
Air getting into the pump?
Send a photo of the pump lid and its O-ring with the pump model. We will advise on the right replacement.