What is a monobloc heat pump and what are their pros and ...

What exactly is a monobloc heat pump? As you explore the variety of heat pump technologies available today, you may stumble upon several models and feel overwhelmed by the options. Information from experts indicates that there are two primary categories of heat pumps: ground source and air source, each comprising various models, including monobloc heat pumps.

OUTES provides additional products and information essential for your understanding.

Understanding heat pumps requires familiarization with various types. Initially, you'll notice both ground and air source heat pumps and upon further research, discover the subcategories within air source heat pumps.

Among these, monobloc heat pumps present a unique and efficient air-to-water heating solution, and in this guide, renewables and ventilation installer David Hilton discusses the characteristics and advantages these pumps offer to homeowners.

What is a Monobloc Heat Pump?

Monobloc heat pumps are designed with all refrigerant components housed within the outdoor unit. All refrigerant pipes are factory assembled and hermetically sealed, meaning there's minimal installation hassle.

Two primary types of monobloc heat pumps exist: one with all components integrated outside and another where components are installed inside the home. The former allows for straightforward installation, taking up less indoor space, but does require additional wiring and connections to the outdoor unit.

Furthermore, all pipework for monobloc units remains outside the heated space. This design often safeguards the system by ensuring that a minimal temperature is maintained in the water, even when heating isn't required by the home.

Are Monobloc Heat Pumps a Good Option in the UK?

Because monobloc heat pumps only require minimal connections—electrical wiring and two water pipes—they fit well with the UK’s typically damp and wet climate. However, in colder regions, split systems may perform better since the refrigerant is less likely to freeze in harsh weather. If installed in a cold area, there's a risk that water in pipes could freeze unless treated with antifreeze options.

Glycol is commonly used for this purpose; however, it impacts the thermal efficiency of the water mix. To maintain effective heating, larger pipework is often necessary, and anti-freeze valves may also be incorporated to protect the pump without significant concern.

Most heat pumps maintain a temperature around 20 degrees Celsius, mitigating issues of freezing under normal conditions, although a power failure in extremely cold weather can lead to water release from these valves, which homeowners should be prepared to manage.

How are Monobloc Heat Pumps Different from Split Heat Pumps?

Split systems consist of two separate units—one outside and one inside the building—connected by refrigerant pipes. While split systems may be advantageous in frigid climates, they require a refrigeration expert for installation, making them potentially more costly compared to monobloc units. The latter can rely solely on plumbing and electrical installation, simplifying the process and often reducing costs.

Additionally, due to the compact nature of monobloc units, they tend to be less expensive overall while maximizing external space usage.

What are the Disadvantages of Monobloc Heat Pumps?

Despite their numerous benefits, monobloc heat pumps come with limitations that must be considered. For instance, in highly energy-efficient homes built to Passive House standards, these units may inadvertently consume excess energy to maintain heat when the building itself does not require it. Using specialized designs, such as integrating glycol solutions or opting for split systems, can help optimize their performance.