Frequently Asked Question
Have a question about water heating for your commercial project? From replacement of legacy gas-fired systems to the next generation of low-carbon alternatives, get a quick answer from the hot water specialists
Water Heating FAQs
Low-Carbon Water Heating
What is a low-carbon hot water system?
A low-carbon hot water system uses energy-efficient technologies, such as air source heat pumps (ASHP) or solar thermal systems, to reduce carbon emissions and energy consumption while providing hot water for residential or commercial use.
What are the benefits of using low-carbon hot water systems?
- Reduced carbon emissions: These systems use renewable or energy-efficient technologies, lowering environmental impact.
- Lower running costs: Improved efficiency reduces energy consumption, saving money on utility bills.
- Compliance with regulations: Helps meet sustainability goals and comply with environmental standards.
- Long-term cost savings: Lower energy usage results in reduced operational costs over time.
What are the key design considerations for low-carbon hot water systems?
- System type: Choose between dynamic (high energy input, low storage) or storage (low energy input, high storage) systems based on demand patterns.
- Heat pump size: Minimise the size of the ASHP to reduce upfront costs while ensuring sufficient capacity.
- Efficiency: Maximise the ASHP’s efficiency (COP) by optimising flow and ambient temperatures.
- Storage volume: Determine the appropriate storage volume based on peak and background demand.
- Controls: Implement simple and effective control systems for efficient operation.
- Space requirements: Consider internal and external space availability for system components.
- Redundancy: Plan for backup systems to ensure reliability.
What is the difference between dynamic and storage hot water systems?
- Dynamic systems: Designed for high energy input and low storage, providing continuous heated water with minimal storage capacity.
- Storage systems: Designed for low energy input and high storage, heating water in large volumes for later use.
What is the best application for a preheat system?
Preheat systems are ideal for hot water systems with peaked demand patterns and minimal background use. They are cost-effective and energy-efficient for applications where hot water is needed in large volumes during specific periods.
What are the environmental benefits of low-carbon hot water systems?
Low-carbon hot water systems reduce greenhouse gas emissions by using renewable energy sources and improving energy efficiency. They contribute to sustainability goals and help combat climate change.
How can I ensure the reliability of a low-carbon hot water system?
To ensure reliability:
- Include redundancy in the system design, such as an after-heater for backup heating.
- Use simple and effective control systems to manage the heat pump and after-heater operation.
- Regularly maintain the system to prevent issues like refrigerant leakage.
How can Adveco help with low-carbon hot water system design?
Air Source Heat Pumps (ASHP) For Low-Carbon Water Heating
What is the role of heat pumps in low-carbon hot water systems?
Heat pumps are a key component of low-carbon hot water systems. They use renewable energy from air or water sources to preheat water, reducing reliance on traditional energy sources and lowering carbon emissions.
What are the advantages of using air source heat pumps (ASHP) for hot water systems?
- Energy efficiency: ASHPs have high coefficients of performance (COP), meaning they produce more heat energy than the electrical energy they consume.
- Low carbon emissions: ASHPs use renewable energy sources, reducing the carbon footprint.
- Versatility: ASHPs can be used for both preheating and direct water heating applications.
What are the challenges of using heat pumps for hot water systems?
- High upfront costs: Heat pumps can be expensive to install, especially high-capacity systems.
- Electrical infrastructure: Large heat pumps may require significant electrical upgrades.
-Capacity reduction: Heat pump efficiency and output can decrease in colder weather or at higher flow temperatures.
- Refrigerant concerns: Some refrigerants, such as R290 (propane), are flammable and require careful handling and installation.
What refrigerants are used in heat pumps for hot water systems?
- R32: Commonly used in low-temperature ASHPs, with medium global warming potential (GWP) and low flammability.
- R290 (propane): Used in high-temperature ASHPs, offering suitable flow temperatures for hot water systems but requiring careful handling due to its flammability.
How can I minimise the size of the ASHP in my hot water system?
To minimise the size of the ASHP:
- Use a storage system with a large preheat volume to reduce peak demand on the heat pump.
- Optimise the reheat time to allow the heat pump to operate efficiently at lower capacities.
- Use an after-heater to supplement the heat pump during peak demand.
What is the COP of a heat pump, and why is it important?
The coefficient of performance (COP) measures the efficiency of a heat pump, calculated as the ratio of heat output to energy input. A higher COP indicates better efficiency, leading to lower energy consumption and reduced carbon emissions.
How does a heat pump preheat system compare to a high-temperature heat pump water heater?
- Preheat system: Uses a low-temperature ASHP and a large storage volume with an after-heater. It is more cost-effective and has slightly higher efficiency (COP ~2.6).
- High-temperature water heater: Uses a high-temperature ASHP with a smaller storage volume. It provides 100% of the hot water load but has higher upfront costs and slightly lower efficiency (COP ~2.5).
How can Adveco help incorporate heat pumps into my water heating project?
Adveco offers:
- Free CIBSE-approved training
- Expert design services for heat pump-based domestic hot water systems
- Curated range of high-quality ASHPs for commercial-grade water heating
- Nationwide UK sales and support.
- Regional expert sales engineers
- Site surveys and DHW metering and analysis.
Solar Thermal
What is a solar thermal system?
A solar thermal system uses solar collectors to capture the sun’s energy and convert it into heat for producing hot water.
How much of my hot water can solar thermal provide?
In the UK, a well-designed commercial solar thermal installation can typically meet 30% or more of your annual hot water demand.
Can solar thermal work with other heating systems?
Yes — it integrates well with gas, electric, and renewable systems such as heat pumps to form a hybrid hot water solution.
Is solar thermal suitable for retrofit projects?
Absolutely — it’s often installed alongside existing plant to reduce energy use and extend equipment life.
What maintenance does solar thermal require?
Annual servicing is recommended to check the fluid, pumps, and controls, ensuring the system continues to operate efficiently.
How can Adveco support solar thermal in my project?
Adveco offers:
- Unmatched experience in commercial solar thermal design & supply
- Solar thermal panels, drainback and system integration
- Nationwide UK sales and support.
- Regional expert sales engineers
- Site surveys and DHW metering and analysis.
- Offsite construction services
Commercial Hot Water Cylinders, Tanks, Buffers & Calorifiers
What is the difference between a calorifier and a hot water cylinder?
A calorifier is a type of hot water cylinder that uses an indirect heat source, such as a boiler or heat pump, to heat water via a coil or heat exchanger.
What size commercial hot water cylinder do I need?
The size depends on your peak demand, recovery rate, and available plant room space — our team can provide a tailored specification.
Can I integrate a commercial cylinder with renewable energy systems?
Yes — cylinders can work with solar thermal panels, air source heat pumps, and other low-carbon technologies.
What is an unvented cylinder and why use one?
An unvented cylinder connects directly to the mains, delivering high water pressure without the need for a cold-water storage tank.
Do commercial cylinders need regular maintenance?
Annual servicing is recommended to ensure safe operation, maintain efficiency, and extend lifespan.
How can Adveco help with cylinders in my water heating project?
Adveco offers:
- Free CIBSE-approved training
- Expert design services for domestic hot water systems
- The widest range of commercial hot water cylinders in the UK
- Nationwide UK sales and support.
- Regional expert sales engineers
- Site surveys and DHW metering and analysis.
- Offsite construction services