Commissioning is a crucial process that ensures ASHP installations are completed to a high standard to operate at peak efficiency. Here, Paul Bailey, Heat Pump Engineer at Baxi, discusses how commissioning also safeguards the installer’s professional reputation and mitigates the need to come back for adjustments, corrections, or premature maintenance and repairs.
The steps to successful commissioning begin long before the installation itself.
Heat loss calculations
These are essential for balancing the energy requirements of a home with the naturally occurring heat loss that occurs via the building’s fabric. With thorough and accurate heat loss calculations, installers can provide the most effective and efficient ASHP system, including radiators, for their customers.
To accurately perform heat loss calculations and therefore be able to correctly size an ASHP, installers need to look at a number of details. Window size and glazing should be considered, in addition to the size of the building and each of its rooms. Armed with this information, installers can calculate the rate of heat loss and recommend an ASHP that overcomes heat losses and ensures customers are comfortable and warm.
Positioning
As part of commissioning, the placement of an ASHP will be checked to ensure it’s in a location that allows for effective air intake and expulsion. ASHPs should always be positioned close to the property, using minimal pipework and enabling easy access for servicing and maintenance.
Recent changes to government regulations from the Department for Energy Security and Net Zero (DESNZ) mean that, in England and Wales, ASHPs can now be placed less than one metre from buildings, making installations more accessible to homes on smaller plots.
It is important to keep in mind that ASHPs should not be tight against a wall or other surface as some space is required for the systems to expel cold air, but should be somewhat sheltered from open space and wind.
The same government update now means that ASHPs for houses can be almost three times larger – from 0.6m3 to 1.5m3 – without needing to secure planning permission. This creates an easier route for more households to take advantage of ASHPs.
Once sited on a solid, flat surface, it is advisable to carry out checks to ensure the ASHP performs to the level set out in the heat loss calculations. If the system, including all radiators and emitters, has been accurately sized, the building should feel comfortably warm, even if the radiators are not hot to the touch.
Manufacturer guidelines
One of the primary goals of commissioning is to ensure the installation meets the manufacturer’s instructions. It’s a chance to check and optimise settings to complement the system design and customer requirements.
ASHPs are usually very reliable appliances, so when something goes wrong or performs in an unexpected way, it is normally an issue with the wider system. The most common faults tend to be down to system design, installation or incorrect settings – understandable mistakes considering how new ASHPs are to many installers.
This relative unfamiliarity is one of the reasons Baxi offers an assisted commission on the first installation to ensure any errors are caught and corrected.
Insist on assistance
Commissioning also serves as a chance to educate customers on heat pump operation so they receive all the benefits of an effective renewable heating system.
As part of Baxi’s assisted commissioning process, an engineer will walk through the work undertaken with the installer. Every aspect is covered by a checklist to ensure every installation is of a standard and quality the installer, customer and manufacturer can all be happy with.
For example, some of the first points on the checklist include the ASHP’s position on a solid base, condensate drainage and minimum clearances around the appliance. Towards the end of the process, commissioning looks at scheduling domestic hot water times and temperatures for the customer.
It’s important not to think of commissioning as an exam to pass or fail. Instead, it’s a chance to confirm the quality of work carried out and solidify the installer’s professional reputation in the eyes of their customer. This can be a great help when it comes to word-of-mouth referrals. Should issues need to be rectified, they can almost always be done there and then, with a little guidance from the commissioning engineer. A bonus of this process is any mistake that does need correcting tends not to happen again as it sticks in the installer’s mind.
Ultimately, commissioning is about making sure installers are supported in their heat pump projects and homeowners receive the comfort and energy efficiency they expect. The benefits of commissioning are that customers are kept happy, installers’ reputations are secured and their next ASHP projects will go even better as their experience and confidence grows.
