Might it be possible to include features which encourage more monitoring of air-to-air heat pump installations?
No doubt the current heatwave - and the expectation of similar or worse heatwaves in the future - will lead to increased installations of ‘air conditioning’ systems.
In some ways this increased take-up could be considered A Good Thing, since these are still ‘heat pumps’ and can be used for (supplementary?) heating in cold weather - and I’m not hearing anyone claim that “air conditioning doesn’t work” so one outcome might be increased confidence in heat pump technology.
However, if there are a lot of poor-quality installations of poor-quality devices, that might lead to reduced confidence in heat pumps - or at least in the affordability of their running costs.
The recent thread started by @SarahH highlighted that we don’t have much real-world data for air-to-air systems, so it’s difficult to weigh up the pros and cons of the various options.
Questions it would be great to be able to answer include:
- Are the ‘premium’ brands worth the extra cost, especially if systems are only used for a few weeks a year (and so efficiency and reliability are not as critical)?
- For example, are the controllers in the premium systems ‘better’?
- Is it preferable to have one External unit driving multiple Internal units, or to have Internal and External units paired 1:1 (typically leading to multiple External units being required)?
- How does the efficiency in Heating mode compare with the efficiency in Cooling mode?
- Is performance maintained over the life of the installation?
- For example, is on-site-terminated refrigerant pipework more prone to leaks than the factory-terminated pipework in air-to-water heat pumps?
- If someone has both an air-to-water heat pump (for heating and hot water) and an air-to-air heat pump (for ‘air conditioning’), what are the pros and cons of using either or both systems for heating?
- Are there implications for right-sizing an air-to-water heat pump if there’s also an air-to-air heat pump available for supplementary heating?
I guess the big challenge is metering the heat output from these systems, since it’s not simply a case of fitting a third-party heat meter.