Heat pump cover assessment: airflow and temperature
Technical centre · Blade and Big Blade
Assess a heat pump cover against the actual outdoor unit and site layout, rather than dimensions alone.
This checklist helps installers and building services engineers prepare a specification and organise site observations. Start with the installation instructions for the exact unit.
Finish
Anthracite can become warm in sunshine. Panel temperature and entering-air temperature are different measurements.
Construction
Aluminium composite panel is part of the cover design; it does not replace ventilation.
Air route
Check intake, discharge and nearby obstructions together to identify possible recirculation.
1. Build the specification
- Equipment: exact model and version, refrigerant and installation manual.
- Overall dimensions: include brackets, pipework and projecting components.
- Location: wall-mounted, ground-mounted against a wall or freestanding; provide photographs of the surrounding space.
- Access and drainage: required clearances, service panels, condensate and defrost-water routes.
- Exposure: orientation, sunlight, wind and other equipment near the air paths.
2. Separate the measurements
| Measurement | What it tells you |
|---|---|
| External panel surface | Shows surface heating. An infrared image does not measure air temperature. |
| Reference ambient air | Provides a comparison away from the discharge plume, with the probe protected from solar radiation. |
| Entering air | Measure at representative inlet positions using suitable air probes. |
| Operating conditions | Record mode, load, sunlight, wind and defrost status alongside the readings. |
Entering-air versus ambient temperature is diagnostic information. It cannot, on its own, establish a change in COP or seasonal energy use.
3. Review the proposed arrangement
- Read enclosure restrictions: check the unit manufacturer’s instructions before adding cladding.
- Trace intake and discharge: include louvres, walls, recesses and adjacent plant; look for discharge air returning to the inlet.
- Check maintenance and drainage: retain the required access and discharge routes.
- Document operation: comparisons with and without a cover require comparable conditions; assess defrost separately.
There is no universal cover gap or acceptable temperature rise for every unit. Site readings supplement the manufacturer’s requirements and do not constitute an efficiency certification.
4. Specifying anthracite and ACP
Blade and Big Blade are available in anthracite as well as white. The polymer core changes conduction through the aluminium composite panel compared with solid aluminium. A thin panel is not insulation for the complete heat pump: opening geometry and entering-air conditions remain part of the assessment.
Read the explanation of anthracite covers, temperature and heat pump airflow.
5. Choose the cover configuration
Blade anthracite and Big Blade suit different unit sizes and layouts. Big Blade combines a supporting stainless steel frame and ACP cladding. Record the proposed setting of its manually adjustable louvres.
For R290 units, check the model-specific protective zone and refrigerant-dispersion requirements. Planning and other local installation requirements must be assessed separately from the cover finish.
Installer questions
Does anthracite automatically reduce efficiency?
Colour alone proves neither a penalty nor zero loss. Assess the unit, cover and location together.
Is sufficient internal space enough?
No. Air paths, technical clearances and service access also need to be compatible.
Can panel temperature establish COP?
No. Surface temperature is not a measurement of heat pump efficiency.
Prepare a project review
Send the data plate, manual, dimensions and site photographs to help assess the appropriate size and configuration.
Send unit and site detailsOpen the configuratorDocumentation: Box Air Klima construction; example manufacturer instructions for clearances and R290 protective zones. This example does not certify a cover-and-unit combination; use the actual unit’s manual.
Technical guidance updated 29 October 2026.