Split Air con

[YoungBlood]

Spoiler

Anybody have a split air con setup?
I'm wondering if I could get away with a unit installed on the wall in red (external wall).
The green is the "landing upstairs"

If we assume all the upstairs doors are always open, and the main source of summer heat is actually that red wall (their is a huge window that catches the sun in summer) the bedrooms don't catch the sun at all but heat up from the huge amount of heat radiating from the landing.

I also like the idea of it here, as during winter it would be better to have it doing it's background heat thing on that wall rather than stuck in a single room, and it would be used for heating about 45 weeks of the year.

Anybody gone for a landing install rather than a bedroom? How did it work out.

 

[YoungBlood]

Ah perfect, guess a fan by the door sucks in the cold air?
My main concern is the noise of the outside unit, it will mainly run at night, and of course during summer people have the windows open, with the neighbors window being a garage door width away I'm hoping they don't go thud thud thud like the portable ones do. With the compressor kicking on and off.

@RJC can I ask what BTU you have?

 

[YoungBlood]

Rather than winging it why not a split unit ducted to each room and the return in the hallway?

They aren't that much more money really because they don't come with the plastic housing and have to be as small as possible?

That's what we have done this year, yet to use the a/c but the heat function is tip top

Purely cost but I will ask for quotes for this. But if I was going to have a split system I would rather have 1 unit upstairs and 1 downstairs.
It's very open plan 35 Sqm so not huge areas.

Also where do they draw the power from? Does the inside unit power the outside or vice versa? I'm just thinking of possible sources to plum in the electrics.

 

[YoungBlood]

I had mine installed end of January. "Midea Blanc"
I was very skeptical of the brand but it came with a 5 year warranty and has been flawless (as you would expect) the past few months.

Course, due to the weather it has been used for heating and well, the amount of heat they throw out is just insane.
If it cools half as good as it heats, summer this year will be most comfortable

 

[YoungBlood]

Yes I had just the one unit installed as described in the OP.
With the doors left open the entire upstairs is very warm, very quickly.

The only issue, is that due to it's location "on a landing" the indoor unit reads the air temp as much higher than it is, in any given upstairs room, make sense? (the landing is quite a small enclosed space)
So I have to use the follow me mode, where the indoor unit ignores the air temp of where the unit is, and instead takes the reading from where ever the remote control is.

Pop the remote in a corner of a bedroom, and the entire upstairs will be 20c fast and cheaply. Also has wifi so you can switch it on and off from where ever with the App.

Note about noise.
The indoor unit is just silent, no problems there. The outdoor unit, whilst being inverter tech. Well I legitimately thought a helicopter was landing in the back garden, one time. Was quite shocked when it turned out to be the outdoor unit.
Lets just say it has a lot of power to draw on if it ever needs it to cool, but 99% of the time you can't hear it, it's just the starting up from cold where it warms the gas up and will run at full tilt for a few minutes, so don't be too alarmed if at 1st switch on it sounds like it will annoy the neighbors, it won't spin like that for long.

When it gets the room to where it needs to be, it will idle quietly and cheaply, around 300w I would say, looking at the smart meter display. Not bad to heat an entire floor.
Has some great ECO options for the summer too, where you can force the power usage to be 100% 75% or 50% of max, also has a silent mode for the outdoor unit.
Then you can press it should it get a little rowdy in the summer nights when the neighbors have windows open. Course cooling/heating capacity is greatly reduced as it forces the compressor to run at a very low rpm.

So yeah, super chuffed with it, and looking forward to some cold summer nights.

 

[YoungBlood]

Nice clean install all round.
Put mine into cold mode for the first time since owning it, seems to use considerably less electricity to cool than it does to heat.
Guess I can get rid of my 18,000! BTU portable A/C now.

How did he supply power to yours? Took a spur off a plug socket?

 

[YoungBlood]

Do you have a smart meter to monitor how much energy your using?

Yup he spurred off a plug socket in my kitchen (other side of the wall). Kinda wish he didn't blob so much clear sealant around the socket. I should have said I would do this myself as I am pretty neat at doing it (can also see a few gaps in the sealant so I will touch those up anyway). I think he said the ring needs to be a minimum of 20A, mine are all rated at 32A though.

Yeah have one of those smart meter displays so easy to see. I'm also on PAYG so cost to run was a big concern.
Luckily my outdoor unit landed right next to my consumer unit so it takes power straight from that.
Isolated twice, one inside the consumer unit cabinet and again next to the outdoor unit.

Just looked and the house will idle @ 250watt.
With the A/C on and set to 18C the whole house consumption is 500watt but it's not having to work very hard, not adsactly in high summer yet.

Compared to the monstrous portable unit I was using the last few years that would use 1.7KW!! 24/7 as it would just fight it's self to cool the room down and never get cool enough to switch it's self off, the amount of heat it threw out the back was just insane and a complete was of time and money (luckily I got the unit free)

Just popped my head outside to see if the outdoor unit was even on as the power is so low, and who would have thought, it's bloody warm out there today
Please don't break down!

 

[YoungBlood]

It aint a problem until it's a problem. (it won't be)
Beneath the window would have been a slightly messier install with the 90 degree piping, and the electrics would have had a worse path through cabinets maybe?
I'm assuming the sink is below the window.

I had this discussion with my installer, he has never had anyone complain about the noise of the outside unit, and as stated above, slightly more to the right would make no odds to the noise.
You can get decibel apps for your smartphone, I imagine it barely registers.
Besides at night I guess only the bedroom would be running, so the outdoor unit won't be stretching it's legs. You probably have a silent mode you can use anyway. On mine it's hold the fan button down.

 

[YoungBlood]

So my first one is in, no issues. It only took them a couple of hours. The inverter is on foam feet on the garage roof and the pipe run is super short to the wall unit, through a 70mm hole. It's at the top of the stairs pointing into the master bedroom.

It's a Mitsubishi Heavy Industries 3.5kw cooling / 4kw heat unit.

Very impressed by how quiet it is. Completely astounded by how much heat it kicks out in heating mode, unbelievable.

The original plan was to have this unit upstairs to take the edge off the bedrooms and another unit downstairs in the living room. When it's hot it's really difficult to keep the upstairs of our house cool. Having had a play with this one today I'm going to hold off on the whole planning permission issue/additional downstairs unit until I've had experience using this one on a hot day. Within 30mins of it being on upstairs is like a fridge and you start feeling it downstairs, and that's on eco mode. Albeit, it wasn't exactly a hot sunny day today. So very interested to see how it performs when things warm up.

Mine is in the same location - works a treat. But! your landing will reach the set temp in minutes and throttle the unit down, leaving your master room too warm or too hot as it will take the temperature from where the indoor unit is located.

So make sure you use the "follow me" function on the remote and place it in the master bedroom pointing towards the unit.
I'm sure you knew this but just in case it will then use the temperature of where the remote is rather than he temperature of the landing.

How is the outdoor unit fixed to the roof? is it simply resting, or did they bolt it into the roof?

 

[YoungBlood]

She is certainly running on the limit through this heatwave, pulling 1KW to keep a room 20c in direct sunlight.
Adjacent room tickling 30c ouchie.

 

[YoungBlood]

Could they hear it in the garden, absolutely.
Could they hear it in their bedroom with a window open, probably not.
It's a nice hum if you know what I mean, like white noise. Just like having a desk fan on by you.

Ditching the god awful portable was the best thing I ever did, and I swear that made more noise you could hear outside than an actual external unit!

Edit
Well mine is a bit no frills brand @fobose so maybe mine is a little louder.

https://www.mideauk.co.uk/air-conditioning/blanc/

 

[YoungBlood]

Anyone know if you get a reversible unit which can also do heating if it's eligible for the RHI scheme?

I looked into it before I had mine installed, short answer no

http://www.legislation.gov.uk/ukdsi/2018/9780111166734/regulation/10

Doesn't comply if it can also cool;
(e)it is not designed to provide cooling

 

[YoungBlood]

Nuts, thought I'd found a way to get subsidised air con

hehe me too for awhile.
I will say though, they are amazing heaters, I would even say they do a much much better job of heating than they do cooling... go figure.

 

[YoungBlood]

I spoke to my engineer about self installs and how technically I could buy the unit he was installing for next to nothing (not that I would attempt myself)
He said a lot of his work comes from repairing these bad self installs, something about them using an inferior quality pipe with a much thinner thickness?

Course there is also the warranty/guarantee to consider, I can run mine as hard as I like knowing it's covered for 5 years, but yes I have had to pay many hundreds extra for that privilege I guess...

 

[YoungBlood]

Has anyone put a temp probe on the cold air outtake and checked the temperature?
Wondering what temp the cold air should be....

Mine has been really struggling today, and the cold air don't feel all that cold still pulling 800 Watts though.

 

[YoungBlood]

You should have approx 12c delta T across the coil.

Is it posiible to feel the suction line?

Whats the suction line? is it inside or out?

 

[YoungBlood]

Ah yes, it's very cold and damp.
Guess it's just at the limit of cooling, now the suns set it's not so bad, 21c indoors.

 

[YoungBlood]

I only have the one.
Should have gone for a higher BTU but was advised not needed.

 

[YoungBlood]

Bit of both, but I have shielded it with a wheelie bin
It's fine 99% of the year, awesome in fact.

Cheap to run, just anything 30c+ outside, and it's at it's max for making the upstairs bearable.
Luckily that 30c is a rare occurrence.

Probably would have been best to leave it on low/silent throughout the day whilst out, so it doesn't have such a mountain of heat to overcome at the evening.

 

[YoungBlood]

Mine is always set to 16c when it's on, course it never gets near that but it ensures the unit doesn't throttle down.
Remember mine is on the landing so I have to set it very low to take the edge of the bedrooms.

Room temp above 20c is too warm for me, I'm stupidly sensitive to heat.
Unit @ 16c = landing @ 21c, bedrooms at 23c but feels cooler..
In retrospect the landing was a mistake, I should have picked a bedroom and put it in there, but the condensate pump noise was an issue.

I work in a greenhouse so you imagine this week has not been my happiest to say the very very least.
Coming home and hugging this bad boy has been the only thing that's got me through the day.