When to Repair vs Replace Your Sewage Pump: A Practical Guide for Homeowners

If your sewage pump has started alarming, stopped working properly, or is causing sewage to back up, one of the first questions is always:

Can this be repaired, or does it need replacing?

It’s a fair question, and one we deal with regularly across Guildford and the surrounding areas.

The honest answer is that not every pump problem means you need a new pump.

Very often, the issue is not the pump itself, but what is happening elsewhere in the system.

That’s why it’s important to understand the cause before rushing into replacement.

When a sewage pump can often be repaired

A pump can often be repaired when the main issue is one of the working components rather than the motor itself.

Common repairable problems include:

• floats stuck with grease or debris,
• blocked non-return valves,
• debris around the impeller, causing a blockage,
• alarm faults,
• electrical issues,
• control panel faults,
• worn seals or minor parts.

Removing the pump for a full inspection allows us to determine whether repair is possible or replacement is the most reliable long-term option. In many cases, we find plastic wrappers, wipes, and other debris wrapped around the impeller, which can often be the root cause of repeated pump failures.

In many cases, a proper clean-down and inspection is enough to restore the system.

We often find that the pump chamber has simply become overloaded with grease, wipes, or debris, preventing the float from lifting properly.

Problems caused by surface water entering the foul system

This is a very important one and something we see more than people realise – Sometimes the pump is working harder than it was ever designed to because surface water is entering the foul drainage system.

This can happen through:

• incorrectly connected rainwater pipes,
• gullies feeding into foul drains,
• broken covers allowing groundwater in,
• cracked drains below ground.

When this happens, every period of rain increases the volume going through the pump chamber.

The pump may seem faulty, but in reality, it is being overloaded.

In cases like this, the repair may involve correcting the drainage issue rather than replacing the pump.

Problems caused by misaligned joints and damaged pipework

Another common issue is defects in underground pipework.

Where joints have become misaligned, groundwater may enter the pipework.

This causes additional water and debris to enter the system, putting extra strain on the pump.

One of the advantages of ASL is that we have specialist equipment that allows us to deal with this properly.

We can usually repair displaced or open joints with a structural liner, preventing groundwater and debris from entering the pipework.

This can make a significant difference to flow.

In these cases, the pump may still be serviceable, but the drainage system itself needs to be corrected.

When replacement is the better option

Replacement is usually the better option when:

• The motor has failed completely,
• the unit is old and unreliable,
• repeat breakdowns are happening,
• parts are no longer available,
• the pump is undersized for the property,
• repair costs are close to a new installation.

Sometimes, continued repair simply becomes a false economy.

The real answer is proper diagnosis

The most important thing is not guessing.

A pump can appear to be faulty when the real issue is:

• excess water entering the system,
• blocked or damaged drains,
• misaligned joints,
• repeated debris build-up.

That’s why we always start with inspection and diagnosis before recommending repair or replacement.

The right answer depends on the whole system, not just the pump itself.

Call ASL on 0800 181 684