Is a multisplit air conditioner suitable for heating?

Each split unit dehumidifies. There are also systems with humidification, e.g. Daikin Ururu Sarara

This thread is about Multi Split!

This thread is about Multi Split!

Good evening Nutshell, and other split/multisplit operators. What is your experience now in winter in the old building for heating? Is there already a tendency regarding comfort and energy consumption visible?

Nothing new in terms of comfort, but I recently discovered that there are some developments or have been developments in this area. For heating operation, I would rely on console units. They release warm air close to the floor and also visually resemble radiators. For example, I find the Daikin unit quite appealing visually, it also seems to be technically good and relatively quiet compared to other console units. Daikin now also offers the combination of climate/heating indoor units with additional hot water generation and storage. This can replace the separate [BWWP]. For smaller residential units, this would be pretty great and presumably significantly cheaper and easier to implement compared to the air-water heat pump solution with a water circuit and conversion to underfloor heating.

We have a large photovoltaic system (14.6kwp) and a pellet system, underfloor heating on the ground floor (170m2) and radiators + split air conditioners in every room on the upper floor. In addition, the bedrooms, kitchen, and living room on the ground floor each also have a split air conditioner. In the living room 5.1kw, the rest 3.4kw. Each split air conditioner is connected to a smart meter.

Today I simply measured for this thread. Outside temperature 4°, desired temperature in the office (upper floor) 20°, radiator turned off last night. The room on the upper floor was only renovated this year according to KFW standard, triple-glazed and accordingly insulated. The house was built in ’83. Exterior wall Poroton/brick with formerly 8cm air gap and now with blown-in insulation. The room has about 25m2 floor area:



Consumption since this morning at 8:00 (turned on): 2.7kwh, i.e. 320 watts per hour.

Usage since this morning at 8:00 (switched on): 2.7 kWh, so 320 watts per hour.

What exactly does the smart meter measure?
Heat quantity? Electricity consumption of the indoor unit? Outdoor unit?

The indoor units shouldn’t actually consume that much; the main work is done by the compressor of the outdoor unit. The indoor units basically only have the ventilation as power consumption. And a 320W fan would be quite loud.
If the SCOP values from the manufacturers are roughly correct, the figures should be somewhere around 3.5-4.x, depending on the device. And thus at least on the level of typical air-to-water heat pump systems with underfloor heating.