Fitted Air conditioning

[surveyor]

Matt p said:

It’ll be down to how much charge is in the unit upto a given max pipe run. This will include meters head and bends not just length.

You may need to add additional refrigerant too, in which case yes an A/C tech will help.

Although it can be difficult to find a tech to help a self installed system.

[Matt p]

surveyor said:

Although it can be difficult to find a tech to help a self installed system.

I’m very much in agreement. Just to add, it’s difficult to find a tech in general. There’s very very few people coming through into the industry. The skills shortage is becoming very apparent now.

[J.R.B.]

A quick sense check on a quote please. I’ve copied below:

Costs below for Mitsubishi Heavy Industries a/c units.

Ive priced for a 6kw multi split with 3.5kw and 2.5kw indoor units.

Have also priced for the standard model and premium model indoor units in case you prefer how one looks over the other - will send spec sheets.

Thought I’d include the cost for 2 separate systems too as it actually works out cheaper than a multi.

Standard multi split - £2900
Premium multi split - £3110
2 separate units - £2700

2 separate units is the ‘premium’ model.

Standard:

https://www.hrponline.co.uk/media/pdf/75/2a/d5/R32...

Premium:

https://www.hrponline.co.uk/media/pdf/ff/41/8f/R32...

[MattyD803]

J.R.B. said:

A quick sense check on a quote please. I’ve copied below:

Costs below for Mitsubishi Heavy Industries a/c units.

Ive priced for a 6kw multi split with 3.5kw and 2.5kw indoor units.

Have also priced for the standard model and premium model indoor units in case you prefer how one looks over the other - will send spec sheets.

Thought I’d include the cost for 2 separate systems too as it actually works out cheaper than a multi.

Standard multi split - £2900
Premium multi split - £3110
2 separate units - £2700

2 separate units is the ‘premium’ model.

Standard:

https://www.hrponline.co.uk/media/pdf/75/2a/d5/R32...

Premium:

https://www.hrponline.co.uk/media/pdf/ff/41/8f/R32...

Straight off the bat, I would enquire into why they are quoting you for 'Heavy Industries' models. Whilst common in commercial industrial settings (and a good quality product), they do tend to be more expensive than the normal Mitsi Electric units and the internal units were never as sleek, especially for domestic settings. They also never (used to) offer the smaller / fancier indoor wall mounted units, and generally noise levels were higher as they slightly less refined.

To be honest, it has been a little while (c.5 year) since I last spec'd or designed a Mitsi split or VRF system, and it possible something something has changed that I am aware of, but I would ask that question of the company that did the quote.

[thebraketester]

Are those prices supplied and installed?

[fastbikes76]

J.R.B. said:

A quick sense check on a quote please. I’ve copied below:

Can’t comment on price or units, but on the multi split VS individual units I can. The bulk of the running cost comes from the outdoor inverter unit rather than the indoor units. So for example I have a 3 way multi split and the energy consumption with just one indoor unit on is around 800w however with all three units on this only jumps up to a 1000w as essentially all you are doing is turning on two additional fans. The compressor is already doing the work for one unit. If you have 2 units you will be doubling your electric consumption.

[mikey_b]

fastbikes76 said:

J.R.B. said:

A quick sense check on a quote please. I’ve copied below:

Can’t comment on price or units, but on the multi split VS individual units I can. The bulk of the running cost comes from the outdoor inverter unit rather than the indoor units. So for example I have a 3 way multi split and the energy consumption with just one indoor unit on is around 800w however with all three units on this only jumps up to a 1000w as essentially all you are doing is turning on two additional fans. The compressor is already doing the work for one unit. If you have 2 units you will be doubling your electric consumption.

Have you measured that with some kind of meter? I'm surprised it adds so little to the consumption - surely with 'the cold' being distributed to multiple units there will be less going to each one, and thus the outdoor unit needs to work much harder to supply sufficient chilled refrigerant for all the indoor units demands. Rather like having 3 radiators rather than one means a boiler has to work a lot harder to supply sufficient heat, it's not a case of 'well the boiler is hot anyway so it won't make much difference'.

[fastbikes76]

mikey_b said:

Have you measured that with some kind of meter? I'm surprised it adds so little to the consumption - surely with 'the cold' being distributed to multiple units there will be less going to each one, and thus the outdoor unit needs to work much harder to supply sufficient chilled refrigerant for all the indoor units demands. Rather like having 3 radiators rather than one means a boiler has to work a lot harder to supply sufficient heat, it's not a case of 'well the boiler is hot anyway so it won't make much difference'.

Yup, measured with a smart plug. I posted about it back a few pages. Mainly out of interest as when I initially fitted it all, I was concerned about potential running costs with the kids whacking it on full and buggering off out with friends for the day.

I get your analogy regarding rads though, as ironically that’s what I do for a living haha. More than happy to do comparison with 1, 2 and then all three units running again.

[J.R.B.]

MattyD803 said:

J.R.B. said:

A quick sense check on a quote please. I’ve copied below:

Costs below for Mitsubishi Heavy Industries a/c units.

Ive priced for a 6kw multi split with 3.5kw and 2.5kw indoor units.

Have also priced for the standard model and premium model indoor units in case you prefer how one looks over the other - will send spec sheets.

Thought I’d include the cost for 2 separate systems too as it actually works out cheaper than a multi.

Standard multi split - £2900
Premium multi split - £3110
2 separate units - £2700

2 separate units is the ‘premium’ model.

Standard:

https://www.hrponline.co.uk/media/pdf/75/2a/d5/R32...

Premium:

https://www.hrponline.co.uk/media/pdf/ff/41/8f/R32...

Straight off the bat, I would enquire into why they are quoting you for 'Heavy Industries' models. Whilst common in commercial industrial settings (and a good quality product), they do tend to be more expensive than the normal Mitsi Electric units and the internal units were never as sleek, especially for domestic settings. They also never (used to) offer the smaller / fancier indoor wall mounted units, and generally noise levels were higher as they slightly less refined.

To be honest, it has been a little while (c.5 year) since I last spec'd or designed a Mitsi split or VRF system, and it possible something something has changed that I am aware of, but I would ask that question of the company that did the quote.

A good question, and i can't say I know the answer. He did say something about this or a Toshiba system being what he tends to install but essentially said he will fit whatever we want. I can ask though. Is there any particular system that you would recommend?

[J.R.B.]

thebraketester said:

Are those prices supplied and installed?

Yes, supplied and fitted in to a loft conversion.

[J.R.B.]

fastbikes76 said:

J.R.B. said:

A quick sense check on a quote please. I’ve copied below:

Can’t comment on price or units, but on the multi split VS individual units I can. The bulk of the running cost comes from the outdoor inverter unit rather than the indoor units. So for example I have a 3 way multi split and the energy consumption with just one indoor unit on is around 800w however with all three units on this only jumps up to a 1000w as essentially all you are doing is turning on two additional fans. The compressor is already doing the work for one unit. If you have 2 units you will be doubling your electric consumption.

That's interesting - hadn't thought of that. Not that I think it would be an issue in reality as it's unlikely the two systems would be used at the same time - one would be in the office (so used during the day) and one in the main bedroom (so used at night).

[Matt p]

Mitsi heavies have been available as the cheaper Mitsi product.

Multi splits are good from a cost to install perspective, however if it conks out, you’ll loose the whole system.

Toshi’s are decent as are Samsung, Daikin and Hitachi. I’d avoid LG like the plague.

[Matt p]

fastbikes76 said:

Can’t comment on price or units, but on the multi split VS individual units I can. The bulk of the running cost comes from the outdoor inverter unit rather than the indoor units. So for example I have a 3 way multi split and the energy consumption with just one indoor unit on is around 800w however with all three units on this only jumps up to a 1000w as essentially all you are doing is turning on two additional fans. The compressor is already doing the work for one unit. If you have 2 units you will be doubling your electric consumption.

May I ask which system you have?. 800w for a three way multi split is pretty decent. I guess all three are set to 20-21 degrees and left cycling on and off while in use?.

Edited by Matt p on Monday 27th June 11:19

[OldGermanHeaps]

How practical would it be to dismantle a dehumidifier and turn it into a temporary jerryrigged portable air conditioner for my well insulated 4.8mx4.8m garden gym?
I have a plan for later in the year, in my bedroom i have a mitsi heavy single unit split, i want to get a 5 unit multi split for the house and refit the single unit in the gym but i need to save for a few months to acheive that. That will take care of gas eventually getting phased out, and solar and a small wind turbine should help a little bit with the bills.
I was wondering if i could cheat a bit with the dehumidifier just to take the edge off the sweatiness in the gym over summer.
Also any recommendations on who makes the least ugly indoor units?

Edited by OldGermanHeaps on Monday 27th June 11:40

[Matt p]

Throw a wet towel/dish cloth over the intake for the fan. It’ll work for a while, however it’s proper Heath Robinson.

[fastbikes76]

Matt p said:

May I ask which system you have?. 800w for a three way multi split is pretty decent. I guess all three are set to 20-21 degrees and left cycling on and off while in use?.

Edited by Matt p on Monday 27th June 11:19

I have an eleqtrix (sp?) unit which I believe runs the Toshiba compressor.

I’ve just cleared the smart plug and run a few tests at 15minute intervals

With one bedroom on coldest setting and turbo mode on it used a peak of 481w which had settled down to 390-400w’s of continuous running



First bedroom left on as above but second bedroom turned on coldest setting and turbo mode. Peak consumption rose to 961w although again it settled down to closer to 800w



And with all three units running flat out it didn’t reach any higher peak but ran constantly around the mid 900’s rather than dropping down like the other two units. I guess as the compressor was already running flat out the third unit added no extra load apart from internal fan which only draws around 50w shown on smart plug.



This is when I first turn it on but before compressor valves opened and kicked in. Appears indoor units only draw around 50w



Smart plug is accurate enough for my tests given my 3kw pool heater draws 3000w and my 2kw garage heater pulls 2000w’s give or take 10w’s or so on it.

[OldGermanHeaps]

Matt p said:

Throw a wet towel/dish cloth over the intake for the fan. It’ll work for a while, however it’s proper Heath Robinson.

Where would the heat exhaust in that scenario? It would still be a net inpur of heat into the room at that point. I was more thinking of opening tje unit up and fitting a flexible duct immediately after the evaporator to steal the cool air before it gets reheated in the condensor.

[J.R.B.]

So for Toshiba it's c.£100 extra per unit and for Mitsubishi Electric it's c.£300 extra per unit. To be honest I'm OK with the looks of the MHI 'premium' units. Does the fitted price of £2,700 for this seem reasonable?

[PhilboSE]

Time for me to get a split system installed in my garden room; it's 30m2 with a 2.4m ceiling. Ultra insulated (140mm PIR) and airtight. Thermal gain is relatively low due to the aspect - I've been working in the room the last few weeks finishing the internal fit out and it's actually been cooler inside than outside.

Last year I had a quote for a 5kW Panasonic system supplied and fitted £1560. This included £380 for "additional parts" which IMO was just extra profit padding on the quote as I can't see what would be needed beyond what is included in the box. However one year later and the company want £1900 today. Have contacted others and they are coming in around the same price, usually for 3.5kW systems. This is beyond my cost vs convenience threshold so I'm now looking at self install and paying an F-Gas registered person to commission it. A few questions:

Anyone got experience with something like this CoolEasy company? Did it work out OK?

Is there any significant difference between Panasonic, Hitachi, Daikin or any of the less recognisable names?

I've built a raised ground-based plinth for the exchanger, and an external isolator with dedicated supply. Is installation (not commissioning) a case of fixing the two units in place, core drilling a suitable hole and then just feeding pipes through? I've got a location for the condensate drain to attach to a pipe run that leads to a soakaway.

Cheers!

[MrAndyW]

Used cool easy in February. Great to deal with. Very tidy fitting and good workmanship. Would definitely recommend.
Think it was 50% when ordered and the rest on completion.