What is the difference between a CP12 and a CP42 certificate?

A CP12 is a landlord's gas safety certificate for residential rental properties. A CP42 is a commercial gas safety certificate for non-domestic premises such as hotels, offices, schools, and care homes. Both require annual renewal by a Gas Safe-registered engineer.

Commercial Boiler Installation Liverpool - Hotel Manager Saved Guests From Carbon Monoxide Leak In Liverpool Aigburth Hotel

Chris Welford
21 hours ago
12 min read

Key Facts: Liverpool Aigburth Hotel Incident

Date: 18th December 2025
Location: Liverpool Aigburth Hotel, Aigburth Drive, Liverpool
Situation: Legacy heating system required complete replacement following CO detection
Outcome: The hotel manager was hospitalised for 15 days with CO poisoning
Solution: DD Wilson Gas And Heating Engineers has now been hired to make the building safe, so business can resume promptly, by installing two Keston Heat 55 commercial boilers and fixing the flue.
Contact: DD Wilson Gas And Heating Engineers - 0151 739 8945

Close-up of metallic ductwork in an industrial setting, with reflective surfaces and some text on the pipes. Gray and silver tones dominate.

A Professional Response

The hotel's carbon monoxide alarms activated exactly as designed, and staff responded immediately. The ownership moved quickly to commission a complete system replacement to the highest standards, selecting DD Wilson for our commercial heating expertise.

On 18th December 2025, guests at the Liverpool Aigburth Hotel were evacuated after carbon monoxide alarms detected dangerous levels of the gas in the basement. While most occupants escaped unharmed, hotel manager Hassan spent 15 days in hospital fighting carbon monoxide poisoning. DD Wilson Gas and Heating Engineers has been contracted to replace the existing heating system and ensure this never happens again.

This incident demonstrates exactly why the hotel's investment in carbon monoxide detection systems proved so valuable. When the alarms activated, the response was immediate. Here is what happened and how we are making it right.

What Happened at Liverpool Aigburth Hotel on 18th December 2025

At approximately 6:42 am on 18th December 2025, carbon monoxide alarms activated at the Best Western-owned Liverpool Aigburth Hotel on Aigburth Drive. Merseyside Fire and Rescue Service arrived within seven minutes, with crews wearing breathing apparatus entering the basement to investigate.

Fire crews quickly confirmed what they suspected; carbon monoxide readings in the basement were dangerously high. The entire hotel was evacuated as a precautionary measure, with the North West Ambulance Service called to assess all occupants.

Among the guests was Darryl McCrary, a 60-year-old visitor from Texas on his second day in Liverpool as part of a retirement holiday. He described being woken by the smoke alarm just after 6 am, only to be told later that the building was being evacuated due to a carbon monoxide leak. He had to rush to get dressed, grabbing his suitcase with his passport inside, and didn't even have time to put on his socks.

Fortunately, the guests and most staff showed no signs of carbon monoxide exposure when tested by paramedics. But hotel manager Hassan was not so fortunate.

Industrial pipes and valves with silver insulation, set in a mechanical room with a concrete floor. Red and yellow details are visible.

The Human Cost: A Hotel Manager Fights for His Life

Hassan was among the first to detect that something was wrong. When he realised there was a gas leak, he acted quickly to turn off the gas supply and evacuate the building. His actions almost certainly prevented a far worse outcome for the hotel's guests.

But in doing so, he exposed himself to dangerous levels of carbon monoxide. After ensuring everyone was out, Hassan collapsed and was rushed to the hospital. He spent 15 days receiving treatment for carbon monoxide poisoning. He is fortunate to be alive.

According to the Health and Safety Executive (HSE), around seven people die every year in the UK from carbon monoxide poisoning caused by gas appliances and flues that have not been properly installed, maintained, or adequately ventilated. This is why annual boiler servicing is essential for all properties. Hassan's story could have been one of those statistics. Instead, it is a wake-up call for every commercial property owner in the Northwest.

The Statistics: Why Commercial Gas Safety Cannot Be Ignored

The Liverpool Aigburth Hotel incident is not an isolated case. The data paints a concerning picture of carbon monoxide risk and the consequences of non-compliance in the UK. Commercial boiler installation in Liverpool by DD Wilson Gas and Heating Engineers.

Carbon Monoxide Poisoning Statistics

UK Carbon Monoxide Statistics (Source: HSE, CO-Gas Safety, ONS, Department of Health)
Statistic	Figure	Source
Annual deaths from CO poisoning (gas appliances)	7 per year	Health and Safety Executive
A&E cases for CO poisoning annually	4,000 per year	Department of Health
Hospitalisations from CO poisoning	200 per year	Chief Medical Officer for England
Total recorded CO deaths since 1995	733 deaths	CO-Gas Safety Charity
Percentage of CO deaths from boilers	26% of all cases	CO-Gas Safety Charity
Annual deaths from all CO exposure	60+ per year	Office for National Statistics
Homes with CO alarms	Less than 10%	Liverpool John Moores University

Across the UK, the data highlights why proper detection systems like those at the Aigburth Hotel are so important.

For landlords and commercial property owners specifically, failing to maintain valid gas safety certificates can result in fines of up to £6,000 per offence and up to six months imprisonment. If a fatality results from non-compliant gas systems, those responsible could face manslaughter charges.

The existing flue configuration presented challenges that our new design resolves completely.

The original flue system, which ran the full height of the building, had developed an internal fault. This meant exhaust gases were no longer being safely expelled outside, causing carbon monoxide to accumulate in the basement plant room.

Under the Gas Safety (Installation and Use) Regulations 1998 and BS 5440 standards, flue systems must comply with strict length, routing, and termination requirements. The existing system had reached the end of its serviceable life. Our redesigned installation eliminates the need for the original five-storey flue run entirely.

The Health and Safety Executive has been involved in this case, and they will require full documentation and sign-off once our installation is complete. Both the HSE and Gas Safe Register may conduct inspections at any time.

The heating system has been taken out of service while we complete the new installation.

The Regulations, What Commercial Property Owners Must Understand

The Gas Safety (Installation and Use) Regulations 1998 are clear about the responsibilities of employers and those in control of commercial premises. Under Regulation 35, it is the duty of every employer or self-employed person to ensure that any gas appliance, installation pipework, or flue installed at any place of work under their control is maintained in a safe condition to prevent risk of injury.

For commercial properties, this means:

Gas Safe-registered engineers must carry out all gas work
Annual safety inspections are essential, not optional
Flue systems must comply with BS 5440 standards for length, routing, and termination
Records of all gas safety work must be maintained for at least two years
Carbon monoxide alarms should be installed and regularly tested
CP17 commercial gas safety certificates must be renewed annually

Our Solution - Keston Heat 55 Commercial Boilers

DD Wilson is installing two Keston Heat 55 commercial boilers to replace the existing system. We selected Keston specifically because of their suitability for challenging commercial installations like the Aigburth Hotel.

Why Keston Heat 2 Series

The Keston Heat 2 series is one of the market-leading solutions for problematic domestic and commercial installations. While a traditional boiler uses a concentric flue and must be housed on an external wall, the Heat 2 offers up to 18 metres of twin flue capability. This flexibility is precisely what the Aigburth Hotel requires for a commercial boiler installation in Liverpool, Aigburth. Crucially, our new installation will terminate the flue externally above a lamp at low level, rather than requiring a five-storey vertical run. This is not only significantly safer but also more aesthetically pleasing for the property and less of a maintenance burden in the future.

Technical Specifications For Commercial Boiler Installation In Liverpool Aigburth Hotel

Keston Heat 55 Technical Specifications
Feature	Specification
Output Capacity	55kW per unit (110kW total for twin installation)
Part-Load Efficiency	Up to 110%
NOx Rating	Class 6 (lowest emissions category)
Twin Flue Capability	Up to 18 metres
Cascade Capability	Up to 330kW when combined
Built-in Pump	Yes (eliminates external pump requirement)
Warranty	5-year parts and labour
Commissioning	Free commissioning included

The Full Installation Scope

Our work at the Aigburth Hotel includes:

Installation of two Keston Heat 55 commercial boilers
Complete removal of the existing five-storey flue system (internal and external)
New twin flue installation terminating at low level externally
New 100-litre expansion vessel
New micron filter for system protection
Micro-fill system installation
Removal of existing external pumps (Keston boilers have built-in pumps)
Full commissioning and Gas Safe certification
Complete documentation for HSE sign-off

The 35mm isolation valves are already in place, simplifying the installation. We estimate three days for completion.

Safe Removal of the Existing Flue

Removing a five-storey external flue is not straightforward. We are bringing in a cherry picker to disconnect and remove the external sections safely. As our engineer noted,

"You can't just leave sections dangling with clips. When the system goes cold, those sections will drop through."

This attention to detail is critical. A rushed or careless removal could create new hazards for hotel staff and the public. Every section of the old flue will be carefully dismantled and disposed of properly.

Warning Signs - How to Know If Your Commercial Heating System Is at Risk

Every commercial property owner should be aware of the warning signs that suggest a heating system may be unsafe. If you notice any of the following, contact a Gas Safe registered engineer immediately:

Yellow or orange boiler flames instead of crisp blue
Soot or staining around the boiler or on walls near the flue
Pilot lights that frequently blow out
Increased condensation on windows in the boiler room
Unusual smells when the heating is running
Staff or occupants experiencing headaches, nausea, dizziness, or flu-like symptoms that improve when they leave the building
Visible damage, corrosion, or deterioration of flue components

Carbon monoxide itself is colourless and odourless, which is why it is called the silent killer. The symptoms of carbon monoxide poisoning are easily mistaken for other illnesses, including the flu, food poisoning, or general fatigue. If multiple people in a building are experiencing similar symptoms that improve when they leave, carbon monoxide should be considered as a possible cause.

For Landlords and Commercial Property Owners - Your Legal Obligations

If you own or manage commercial property with gas appliances, your legal obligations are clear:

Annual Safety Checks / All gas appliances, flues, and pipework must be inspected at least once every 12 months by a Gas Safe registered engineer. For commercial properties, this typically requires a CP17 commercial gas safety certificate.

Maintenance Records / You must maintain records of all gas safety inspections and any remedial work carried out. These records should be kept for at least two years and made available to the HSE upon request.

Competent Engineers / All gas work must be carried out by Gas Safe-registered engineers who are qualified for the specific type of work required. For commercial installations, additional qualifications may be needed. You can verify any engineer's qualifications on the Gas Safe Register website or by calling 0800 408 5500.

Carbon Monoxide Alarms / While not legally required in all commercial premises, the HSE strongly recommends them, and they could make the difference between a minor incident and a tragedy.

Prompt Remediation / If any defects or safety issues are identified during an inspection, you must arrange for repairs to be carried out promptly. Using condemned or unsafe equipment is a criminal offence.

For landlords of residential properties, the requirements are equally stringent. You can learn more about your obligations on our landlord certificates page.

Glossary - Understanding Commercial Gas Safety Terms

Carbon Monoxide (CO)

A colourless, odourless, tasteless poisonous gas produced by the incomplete burning of carbon-based fuels and often called "the silent killer" because human senses cannot detect it.

CP17 Certificate

A commercial gas installation safety report is issued by Gas Safe-registered engineers following inspection of gas systems in non-domestic premises such as hotels, offices, and commercial buildings.

CP12 Certificate

A landlord's gas safety record (also known as a gas safety certificate) is required annually for all rental properties with gas appliances. See landlord certificates.

Flue

A pipe or duct that carries exhaust gases from a boiler or other combustion appliance safely to the outside of a building.

Gas Safe Register

The official list of gas engineers who are legally allowed to work on gas appliances in the UK. Registration number for DD Wilson: 583586.

HSE (Health and Safety Executive)

The UK government agency responsible for enforcing health and safety legislation in workplaces, including gas safety regulations.

Condemned (appliance)

A gas appliance that has been classified as unsafe and must not be used until repaired or replaced by a Gas Safe registered engineer.

Frequently Asked Questions: Commercial Gas Safety

How often should commercial boilers be serviced?

Commercial boilers should be serviced at least annually by a Gas Safe registered engineer. Many manufacturers recommend more frequent servicing for high-usage installations. Regular commercial boiler servicing helps identify potential problems before they become dangerous and maintains warranty validity.

What is the fine for not having a commercial gas safety certificate in the UK?

Fines for gas safety breaches can reach £6,000 per offence, with the possibility of six months' imprisonment. For larger organisations, fines can reach millions of pounds. In 2024, National Grid was fined £3.2 million for safety failures. If a fatality results from non-compliant gas systems, manslaughter charges are possible.

What are the symptoms of carbon monoxide poisoning?

Early symptoms include headaches, dizziness, nausea, breathlessness, confusion, and fatigue. These symptoms are often mistaken for the flu or food poisoning. If multiple people in a building experience similar symptoms that improve upon leaving, carbon monoxide exposure should be suspected. Severe exposure can cause collapse, loss of consciousness, and death.

How long does a commercial boiler installation take?

For a straightforward like-for-like replacement, a commercial boiler installation typically takes one to two days. More complex installations involving flue modifications, system upgrades, or multiple boilers may take three to five days. The Aigburth Hotel installation is estimated at three days due to the flue replacement work required.

Who can legally carry out commercial gas work in the UK?

Only Gas Safe-registered engineers who hold the appropriate commercial qualifications can legally carry out gas work on commercial premises. You can verify an engineer's registration and qualifications on the Gas Safe Register website or by calling 0800 408 5500. DD Wilson Gas And Heating Engineers is Gas Safe registered (Registration 583586) with engineers qualified for commercial work.

What should I do if I suspect a carbon monoxide leak in my business?

If you suspect a carbon monoxide leak, evacuate the building immediately and call the National Gas Emergency Service on 0800 111 999. Do not re-enter the building until it has been inspected and declared safe by qualified engineers. If anyone is showing symptoms of CO poisoning, seek medical attention immediately and inform the paramedics of suspected CO exposure.

Does DD Wilson provide commercial gas safety certificates in Liverpool?

Yes. DD Wilson Gas And Heating Engineers provides CP17 commercial gas safety certificates across Liverpool, Wirral, Merseyside, Cheshire, Lancashire, and Greater Manchester. We also offer ongoing maintenance contracts for commercial heating systems. Call 0151 739 8945 or visit to book online to arrange an assessment.

About DD Wilson Gas And Heating Engineers

DD Wilson Gas and Heating Engineers is a family-run gas, heating, plumbing, and bathroom installation company established in 1998. Based in Liverpool, we serve a 40-mile radius including Wirral, Merseyside, Cheshire, Lancashire, and Greater Manchester.

With over 25 years of experience and more than 3,000 five-star reviews on Trustatrader, we have built our reputation on quality workmanship and genuine customer care. Our team includes engineers qualified for both domestic and commercial gas work, including complex installations like the Aigburth Hotel project.