CLEARMASTERS
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The basics
What is a grease trap?
Running a restaurant or any food business is no easy feat, and one of the less glamorous jobs is looking after your grease trap.
A grease trap, or grease separator, is a tank that catches fats, oils and grease (known as FOG) before your kitchen's wastewater goes into the drains. The water cools as it passes through, the fat floats to the top and the food solids sink, so only the water carries on to the sewer.
Fat that gets past the trap ends up in your drains, so we also offer high-pressure jetting to clear FOG build-up. Many kitchens have gullies and interceptors in the yard too, which we can empty on the same visit.
We do this work across Surrey, West Sussex, East Sussex, Kent, Hampshire and London, with tankers and engineers in each area most days.
Over time all that FOG adds up and the trap fills. If it isn't emptied, grease gets through to your drains, where it sets hard and causes blockages, bad smells and flooding.
Why it matters
Why does my grease trap need emptying?
A grease trap only works while there's room for more grease. Once it's full, fat carries straight on into your drains and the public sewer, where it cools, sets and builds up into blockages, including the fatbergs you'll have seen in the news.
A blocked drain in a commercial kitchen can mean closing up until it's cleared.
How often your trap needs emptying depends on its size and how busy your kitchen is. Many kitchens need it every few weeks to every few months. We can recommend a schedule once we've seen yours.
Signs your grease trap is full
- Bad smells around the trap or the kitchen drains
- Sinks and dishwashers draining slowly
- Grease visible near the trap's outlet
- Blockages in the drains downstream
- It's been a while since it was last emptied
On the day
What happens when we empty your grease trap
We fit around your service
We can visit before you open, after you close or on your quiet days, so we're not in the way.
We empty it out
We remove the grease, food solids and wastewater from the trap with a vacuum tanker.
We clean it down
We can clean the inside of the trap so it has its full capacity back, and tell you about anything that needs attention.
You get a waste transfer note
Proof your grease went to a licensed facility, for your records and your duty of care.
Why Clearmasters
Why choose Clearmasters?
You don't want just anyone emptying your grease trap. We'll plan around your kitchen, turn up when we say we will and leave the area clean.
Ask us a questionAlways on hand
Routine visits booked at a time that suits you, and 24/7 call-outs when something goes wrong.
Advice from people who know
Our office team can talk you through your system, your options and the rules, or simply get you booked in.
Trained, friendly engineers
Our engineers work with minimal disruption and are happy to answer any questions while they're with you.
Regular schedules
Set up regular emptying and we'll book you in before your trap fills up.
What our customers say
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Questions answered
Grease trap FAQs
How often should a grease trap be emptied?
It depends on the size of the trap and how much grease your kitchen produces. Many commercial kitchens need their grease trap emptying every few weeks to every few months. The manufacturer's instructions are a good starting point, and we can recommend a schedule once we've seen your trap.
What are the signs my grease trap needs emptying?
Bad smells around the trap, sinks and dishwashers draining slowly, grease near the outlet and blockages downstream are all signs it needs emptying straight away.
What does your grease trap emptying service include?
We remove the grease, food solids and wastewater from the trap, clean the inside if needed, take the waste to a licensed facility and give you a waste transfer note for your records.
Will emptying the grease trap disrupt my kitchen?
We plan our visits around your opening hours, so we can come before you open, after you close or on a quiet day. The trap is back in use as soon as we've finished.
Why is regular grease trap emptying important?
It stops grease getting into your drains and the sewer, where it causes blockages, smells and flooding. It keeps your kitchen running and helps you stay on the right side of your water company.
What should I prepare before you arrive?
Please make sure we have clear, safe access to the trap and its covers, and a route for the hose from the tanker. If you have records of previous emptying, they help us work out the right schedule.
Got a different question? Call 03333 233566 or send us a message.
Related services
Fully accredited & compliant
We're independently vetted and certified so you can trust who you're letting onto your site.
SafeContractor
Health & safety pre-qualification accreditation, verifying our processes meet recognised safety standards.
RISQS
Railway Industry Supplier Qualification Scheme — approved to work safely within the rail industry supply chain.
Achilles UVDB
Utilities Vetting Database membership, confirming we meet the utilities sector's supply chain standards.
Trading Standards Approved
Vetted and approved under the local authority's trusted trader scheme for honesty and fair dealing.
NADC Member
Members of the National Association of Drainage Contractors, the UK trade body for the drainage industry.
Registered Waste Carrier
Registered with the Environment Agency, so your waste is handled and disposed of fully within the law.