Heat Pump Design

Thorough and correct heat pump design is the key to ensuring a successful, efficient heat pump system.

Thorough and correct heat pump design is the key to ensuring a successful, efficient heat pump system.

Heat pump design is so incredibly vital as an undersized heat pump installation will never be able to meet the space heating and hot water demand of the property it’s installed in and an oversized heat pump will never be working hard enough to generate heat efficiently.

It used to be the case that heat pumps were specified based on rule of thumb, but customer, installers and relevant bodies soon realised that this was resulting into bodged installations and inefficient systems. Now, with governing bodies such as MCS in place, heat pump installers are required to justify the size of the unit proposed and adhere to rigorous installation quality.

Ensuring that heat pumps are designed on an individual, property-by-property basis is the best way to ensure that a renewable heating system will run efficiently and cover 100 percent of heating and hot water demand. Design really is paramount.

What are the key components of Designing a Heat Pump?

The main component of heat pump design is to evaluate the energy efficiency and demand of any given property, be it a small cottage or a large commercial building. This is usually done in the form of a heat loss calculation.

The heat loss calculation will usually be carried out following a site survey, for retrofit systems, but can also be completed based on information provided from building plans, in the case of new build and self build projects. The aim of a heat loss calculation is to calculate a total heat demand for the given property, from here a correctly sized heat pump unit can be specified.

In order to carry out a heat loss calculation, information on the following will be required:

  • General property information such as build date and EPC availability
  • Information on hot water consumption and desired room temperatures
  • Existing heating system
  • Room sizings
  • Window sizes, specifications and general condition
  • Radiator sizes, specifications and locations
  • External door locations, specifications and general condition
  • Roof light specifications
  • Wall types and insulation
  • Floor type and insulation
  • Roof type and insulation
  • Number of floors

The importance of a Site Survey of Plans in Heat Pump Design

GreenGenUK will only propose a heat pump system if we are certain it will provide the customer with the degree of heat they require and expect.

As such, we will only generate proposals for our customers following an initial site survey or based on a set of accurate building plans. Both of these tools allow us to accurately and confidently put forward a solution that we can guarantee and prove will meet demand.

These methods allow us to get a feel for the property and attain the information required to undertake a heat loss calculation. Without this information, no company will be able to correctly specify and install a heat pump system.

The results of Good Design

The result of good heat pump design is an efficient heat pump system that is capable of covering all of a customer and property’s heat demand, regardless of outside temperature.

A correctly sized heat pump will be capable of working at or near its capacity the majority of the time – it will not be working too hard nor too lightly. This has many benefits.

The life expectancy of the heat pump unit is increased as less strain is put on the system. This will also reduce the noise output of the unit. Correct design is also a key component of validating manufacturer warranties. Furthermore, an efficient system will be more cost-effective to run.

Bad design can lead to a whole host of problems, most notably an inability to supply the customer and their home or business with enough space heating and hot water.

Incorrect heat pump design that leads to an undersized system will result in a system that will be unable to meet heating and hot water demand leave a customer cold when ambient temperature gets lower. This will reduce the lifespan of the system, due to the strain put on it, and will increase the running costs of the system due to the constant draw for energy. On the other hand, an oversized unit will always be working harder than it needs to be and never hard enough for the heat pump to provide its maximum benefit.

In addition, incorrect heat pump design can invalidate warranty.

Other aspects of Heat Pump Design to consider

In addition to the heat loss calculation, there are other things to consider when designing and specifying a heat pump installation.

For example, the efficiency of a correctly sized heat pump can be impacted by installation. Air source heat pumps, typically, need a metre of space in front of the unit and 300mm behind in order to inhale and exhale the air efficiently. If this isn’t allowed, for whatever reason, efficiency can be lost.

It is also important to take into account the desired room temperature of the customer.

As air source heat pumps are designed to run at lower flow temperatures than traditional fossil fuel heating systems, the ideology is to reduce water temperature flowing through heat emitters in order to maximise the benefit and efficiency of a heat pump system. Considering desired room and hot water temperatures will impact total heat demand and it’s important this is taken into account at the design stage. Required flow temperature will impact the size and number of heat emitters required.

GreenGenUK’s experience in Heat Pump Design

Rob Carey, GreenGenUK’s Managing Director, started the company back in 2011 after working in a previous role designing and specifying heat pump solutions to domestic customers.

Since then, we have grown into one of the South West’s leading providers of heat pump solutions. As such, we have vast knowledge and experience of designing and installing heat pumps on a bespoke basis. Because of this, our customers can have confident that the systems they purchase are accurately designed to meet their individual needs and requirements.

Our heat loss tool is based on current industry standard and is compatible with all the systems we install.

Our detailed quote pack clarifies why we have chosen the system size we have and also provides a host of further information to put the customer in a position to make a justified, informed decision. We understand making the leap into renewables is a big decision for many people and, therefore, we are happy to provide any service we can in order to make the decision more straightforward.

Considering a Heat Pump?

Whether you’re looking to retrofit a heat pump in an existing dwelling or would like some prices and specifications for a new build project that’s on the horizon, GreenGenUK can help.

Contact us today to book your free survey or to ask any questions on heat pumps or our other technologies.