Portable split air to air

NedS

@QrizB I saw this video review yesterday the Midea split unit (the one you didn't buy), and thought of you. Sharing here for those who may be interested.

https://www.youtube.com/watch?v=Pn4u9-my6ys

We don't live in the hot South East, but if we did I think I would be giving serious consideration to such units. Luckily we have an old stone cottage which is like a cave in summer; we were able to keep our bedrooms at 18C even during the recent 35C heatwave.

QrizB

Thanks NedS!

Mine is a lot like that although my "smart home" app isn't quite as fancy and I don't get as many options or any power monitoring.

I'm happy enough with my unit, and UpsideDownFork's video does a good job of showing how they work and what you can expect.

tfhnota

I have my south facing windows blanked off with celotex inserts during the day so little heat gets in, my rear garden a tropical paradise whereas the north front garden in the shade of the house is lovely and cool.

QrizB

I see we now have RED weather warning for Wednesday and Thursday 😲

The split is going to have a good workout!

QrizB

It's been interesting to check the power being drawn as the outdoor air temperature changes.

In the morning, when it was barely any warmer outside than in, the unit was pulling about 400 watts.

Mid-afternoon when the air temperature was more like 30C, it was 700 watts.

The only thing I'm looking forward to about Weds and Thurs is seeing how well the portable split performs when the outside air temperature is closer to 40C!

Edit to add: it's 8pm, the split has been running all day (literally, I left it on overnight) and the energy stats look like this:

I suspect we'll have used a little less than 11kWh by midnight. At my 11p/kWh composite rate (8p nights, 12p days) that'll have cost me about £1.20. for the day Not terrible.

TroubledTarts

Yeah the poor thing is really going to have to earn it's keep this week lol

matt_drummer

https://forums.moneysavingexpert.com/discussion/comment/82044143#Comment_82044143

To put its efficiency into perspective.

I just looked for a comparable day for my A2W heat pump

I used 11kWh (including the water circulation pump) to heat my whole four bedroom house to 22.5c and DHW at an average outside temperature of 7c (low of 1c and high of 13c) The heating used 9kWh and the DHW 2kWh

11kWh for a small split sounds like quite a lot.

Its efficiency cannot be that good?

I know somebody with a 12kW split with 5 indoor units and that has been running all day and night. It has barely used any more than that today.

TroubledTarts

https://forums.moneysavingexpert.com/discussion/comment/82044317#Comment_82044317

I would suggest, as has been pointed out in this post, this is a mid point product between the standalone with big hose units and a professionally installed single unit.

For that reason the efficiency and the fact I believe Qrizb has the unit setup to cool a whole floor maybe the whole house (not just one room) that's on par with what one might expect.

The devil is in the detail with these things as well, low and slow, efficient mode, low fan speed over quick 30 Mon blast full power. We should in most cases think of these units as full on A2W heat pumps. Low and slow and efficient maybe?

QrizB

11kWh for a small split sounds like quite a lot.

Per my energy monitoring plug, the total for the day was 10.47kWh. It's roughly half as much as my old single-pipe unit would have used under the same conditions (in practice I never ran it for 24h straight due to the electricity use and the noise).

Qrizb has the unit setup to cool a whole floor maybe the whole house (not just one room)

It's on my upstairs landing, above my largely open-plan ground floor and with a couple of fans set to waft cold air into my three bedrooms.

The cooling effect can be felt throughout probably 80% of my ~100sq.m. semi.

Its efficiency cannot be that good?

SEER is 5.6 as measured in the lab under standard conditions (27C indoor, 35C outdoor). That's not the best, but my old machine only managed a SEER of 2.5 IIRC.

I know somebody with a 12kW split with 5 indoor units and that has been running all day and night. It has barely used any more than that today.

A.multi split is likely to be more efficient, agreed. It's also likely to have cost more than £750. Horses for courses.

FreeBear

Would be interesting to see a graph plotting indoor/outdoor temperatures and energy consumption against time. I suspect it isn't going to be much worse than heating the place in winter.