High-Pressure Hot Water Systems Installed, Serviced & Repaired by Qualified Engineers
Do you have a modern property, larger family home and/or multiple bathrooms where a consistent supply of high-pressure hot water is essential? Unvented hot water cylinders are an ideal solution for you.



At Mark Abraham Gas, we specialise in the installation, servicing, repair and maintenance of unvented hot water cylinders. Our qualified engineers guarantee every system is installed safely, maintained correctly and operates efficiently, giving you complete confidence in your hot water supply.
Over 30 Years’ Experience
Fully Qualified Engineers
Gas Safe & OFTEC Registered
Honest, Reliable & Professional
Emergency Callout Available
Excellent Customer Reviews
Regular servicing helps maximise system performance and extends the lifespan of your unvented hot water cylinder, so it continues operating safely, dependably and productively throughout the year.
We offer and recommend annual and comprehensive servicing. It allows important safety devices to be inspected and tested while identifying any developing faults before they become costly repairs.

1. Get in Touch
Call us or request a quote online and tell us what you need.
2. We Assess
We visit your property to assess your boiler needs and provide expert advice.
3. We Get to Work
Our engineers carry out the work to the highest standards with minimal disruption.
4. You're Covered
Enjoy reliable heating and complete peace of mind all year round.
Powerful and Reliable Unvented Hot Water Cylinder Performance
Unvented hot water cylinders deliver powerful water pressure, excellent hot water performance and a reliable supply of hot water throughout your home.
At Mark Abraham Gas, we specialise in the installation, servicing, repair and maintenance of unvented hot water cylinders.
Our qualified engineers guarantee every system is installed safely, maintained correctly and operates efficiently, giving you complete confidence in your hot water supply.
Whether you’re upgrading an older cylinder, installing a new system or arranging your annual maintenance, our expertise, quality workmanship and exceptional customer service will help and support you.
Our Service Includes:
- Visual inspection
- Expansion vessel checks
- Thermostat testing
- Immersion heater inspection
- Temperature and pressure relief valve testing
- Pressure reducing valve inspection
- Pipework inspection
- Leak inspection
- General performance testing
- System safety checks
- Operational testing
- Service documentation

Unvented Hot Water Cylinder Repairs
Prompt and Precise Repairs for Unvented Cylinders
At Mark Abraham Gas, we thrive on our prompt, professional and precise repairs to restore your hot water supply. We diagnose and identify the cause of hot water cylinder faults quickly, for example: loss of hot water, inadequate performance, leaks or pressure.
Recommending the most appropriate repair solution, we ensure your system is fully tested before returning it to excellent service.
We Repair Problems Including:
- No hot water
- Poor water pressure
- Water leaks
- Expansion vessel faults
- Immersion heater failures
- Thermostat faults
- Pressure relief valve problems
- Temperature issues
- Pipework leaks
- General system faults
Annual Safety Checks
Protect Your Home with a Professional Annual Safety Inspection
Unvented hot water cylinders differ from domestic hot water systems. They operate under pressure and contain several important safety devices that require regular inspection.
An annual safety check is essential in ensuring these components continue to operate safely and correctly. It importantly reduces the risk of system failure while maintaining optimal and efficient performance.
Our exceptional engineers positively execute comprehensive inspections whilst aligning with current industry recommendations, supplying customers with confidence that their hot water systems remain safe and dependable.
Our Annual Safety Check Includes:
- Temperature and pressure relief valve testing
- Expansion vessel inspection
- Pressure reducing valve testing
- Thermostat operation checks
- Safety control inspection
- Pipework inspection
- Discharge pipe inspection
- Leak detection
- General system condition assessment
- Performance testing
- Safety compliance checks
- Service certification where applicable
Benefits of Annual Safety Checks:
- Improved efficiency
- Increased reliability
- Longer cylinder lifespan
- Early fault detection
- Confirms your system is operating safely
- Tests all critical safety devices
- Reduces the risk of unexpected failures
- Helps prevent expensive repairs
- Provides complete peace of mind for you and your family
