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Advice on connecting an air conditioner

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Howard
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Advice on connecting an air conditioner

#217990

Postby Howard » April 28th, 2019, 6:54 pm

I am considering having two split wall air-conditioning units installed. They will be powered by a unit such as this http://www.mhiae.com/en/SCM40ZM-S Each installer who has quoted for this job tells me that they will not be too expensive to run in the summer and can be used for top-up heating in the winter if necessary.

However the literature says that they require a 16 amp supply.

One installer, who has given me a competitive quote, says that the exterior unit can just be connected to a 13 amp socket. He has installed many of these units and his many customer reviews are impeccable.

The aircon will have light use to reduce the temperature of our main bedroom when the weather is hot. And occasional use to keep a downstairs room cool. The wall units are unlikely to be used at the same time. (I have previously used a portable aircon which is effective but just too noisy).

Whilst I take the comments about low running costs with a pinch of salt, I can’t imagine that my occasional use will involve 16 amps of current. As a layman this doesn’t seem logical.

I’d appreciate any comments on the implications of connecting this unit to a 13 amp socket. The house is around 20 years old with a Crabtree RCD consumer unit.

regards

Howard

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Re: Advice on connecting an air conditioner

#218027

Postby quelquod » April 28th, 2019, 9:58 pm

Well, a (non in-depth) glance at the spec sheet gives a maximum power of 2.13kW and a maximum continuous current of 14A. It’s usual for single phase motors to run at a fairly poor power factor so these figures aren’t necessarily in conflict - the 14A doesn’t necessarily imply a power of the approx 3.5kW you might think. Just to give you an example, my lathe has a 3/4hp - 750 watt - motor which requires 8A.

In your case the electrical power consumption is quoted as under 1kW and this is what will determine your running cost.

It’s obviously pushing things a bit to run a continuous 14A from a 13A socket and it’s bad practice. A 13A fuse is likely to survive for quite a while with such a small overload but it will get hot and the plug and socket may get hot too and give problems in the near term. However there’s no indication of the duty cycle in the brief specification and so the 14A mentioned may well be relatively short duration. Normally the cabling itself to a 13A socket is rated well above 14A but this is still bad practice and your electrician should know better.

In a nutshell running the unit from a 13A outlet will likely be just fine but it would be better practice to run a dedicated 16A supply.

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Re: Advice on connecting an air conditioner

#218031

Postby csearle » April 28th, 2019, 10:38 pm

Howard wrote:I am considering having two split wall air-conditioning units installed. They will be powered by a unit such as this http://www.mhiae.com/en/SCM40ZM-S Each installer who has quoted for this job tells me that they will not be too expensive to run in the summer and can be used for top-up heating in the winter if necessary.

However the literature says that they require a 16 amp supply.

One installer, who has given me a competitive quote, says that the exterior unit can just be connected to a 13 amp socket. He has installed many of these units and his many customer reviews are impeccable.

The aircon will have light use to reduce the temperature of our main bedroom when the weather is hot. And occasional use to keep a downstairs room cool. The wall units are unlikely to be used at the same time. (I have previously used a portable aircon which is effective but just too noisy).

Whilst I take the comments about low running costs with a pinch of salt, I can’t imagine that my occasional use will involve 16 amps of current. As a layman this doesn’t seem logical.

I’d appreciate any comments on the implications of connecting this unit to a 13 amp socket. The house is around 20 years old with a Crabtree RCD consumer unit.

regards
FWIW I agree with everything that quelquod has said. If the manufacturer says it should be run from a 16A supply then to do otherwise would require the installer to satisfy him/herself that doing otherwise is equally safe. If you don't and anything untoward were to happen then the installer would be liable.

In short I would personally go with "best practice" and install a dedicated supply from the consumer unit to the unit with a rotary isolator in the vicinity of the unit.

Regards,
Chris

Howard
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Re: Advice on connecting an air conditioner

#218040

Postby Howard » April 28th, 2019, 11:49 pm

Thank you both for your comments above. The installer specialises in fitting air conditioners but I would like to make sure it is installed "properly". I have previously had some work done by a local electrician who I trust, so will ask them for a quote for a dedicated supply from the consumer unit to the unit with a rotary isolator as you suggest. And then the aircon installer can connect to this.

Your advice is appreciated!

regards

Howard

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Re: Advice on connecting an air conditioner

#218077

Postby quelquod » April 29th, 2019, 9:40 am

quelquod wrote: my lathe has a 3/4hp - 750 watt - motor which requires 8A.


Oops! 1hp of course.

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Re: Advice on connecting an air conditioner

#218095

Postby Itsallaguess » April 29th, 2019, 10:15 am

Howard wrote:
I am considering having two split wall air-conditioning units installed.

They will be powered by a unit such as this - http://www.mhiae.com/en/SCM40ZM-S


Just out of interest Howard, have you got a link to show us which internal units you're planning to use?

Also, as well as the above, are you able to itemise your quotes for each bit of kit, and also installation costs?

I only ask because this type of air-conditioning installation has piqued my interest in the past, so to have someone on the verge of installation, presumably having done some prior investigation work, is very timely.

Cheers,

Itsallaguess

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Re: Advice on connecting an air conditioner

#218108

Postby Howard » April 29th, 2019, 10:58 am

Itsallaguess wrote:
Howard wrote:
I am considering having two split wall air-conditioning units installed.

They will be powered by a unit such as this - http://www.mhiae.com/en/SCM40ZM-S


Just out of interest Howard, have you got a link to show us which internal units you're planning to use?

Also, as well as the above, are you able to itemise your quotes for each bit of kit, and also installation costs?

I only ask because this type of air-conditioning installation has piqued my interest in the past, so to have someone on the verge of installation, presumably having done some prior investigation work, is very timely.

Cheers,

Itsallaguess


Would you bear with me for a week or so, Itsallaguess. As you can probably tell, I'm in the middle of the quoting stage but will make a decision in the next week or two and will then be in a position to give you a more informed reply - watch this space!

At the moment, the quotes I have range between £2.5k and £5k including VAT, for supplying and installing the exterior unit and two internal wall units. The installation is relatively simple but I'm aiming for a solution which is both quiet (internally and externally) and acceptable from a visual viewpoint. The more expensive quote is for a Daikin system which apparently is top quality. However, their wall units are wider than some competitors and unnecessarily complicated for my requirements. Frankly I'm unlikely to spend that amount.

Looking at the internet, I'd guess that for the cheaper quote above, I'm being charged around £1 -£1.5k for fitting. And I expect that the cost of the 16 amp spur may add a couple of hundred to the costs.

I visited a showroom and frankly all of the wall units they stock were incredibly quiet in operation when on their lowest setting. At the moment I'm expecting a Mitsubishi unit to be the best from a size and performance point of view.

Will post an update when I can give more definite information.

regards

Howard

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Re: Advice on connecting an air conditioner

#218131

Postby Itsallaguess » April 29th, 2019, 12:28 pm

Howard wrote:
At the moment, the quotes I have range between £2.5k and £5k including VAT, for supplying and installing the exterior unit and two internal wall units. The installation is relatively simple but I'm aiming for a solution which is both quiet (internally and externally) and acceptable from a visual viewpoint. The more expensive quote is for a Daikin system which apparently is top quality. However, their wall units are wider than some competitors and unnecessarily complicated for my requirements. Frankly I'm unlikely to spend that amount.

Looking at the internet, I'd guess that for the cheaper quote above, I'm being charged around £1 -£1.5k for fitting. And I expect that the cost of the 16 amp spur may add a couple of hundred to the costs.

I visited a showroom and frankly all of the wall units they stock were incredibly quiet in operation when on their lowest setting. At the moment I'm expecting a Mitsubishi unit to be the best from a size and performance point of view.

Will post an update when I can give more definite information.


That would be great Howard, and I'd of course be interested in how you find the new kit, in both operating and operation, regarding controls/noise/etc...

Cheers,

Itsallaguess

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Re: Advice on connecting an air conditioner

#218260

Postby PrincessB » April 29th, 2019, 7:52 pm

am considering having two split wall air-conditioning units installed. They will be powered by a unit such as this http://www.mhiae.com/en/SCM40ZM-S Each installer who has quoted for this job tells me that they will not be too expensive to run in the summer and can be used for top-up heating in the winter if necessary.


Arghh!!!!

These are completely wrong for the UK and you will hate them.

I'm a bit pushed for time at present, but come back with questions and I'll answer in a day or so.

Aircon 101 time:

Within reason, you don't know what the temperature is, you sense radiant heat from the walls and humidity more directly.

Consider how much cooling you're going to get from 4Kw of cold and compare that to the amount of heat a four bar electric fire would put out - Plenty for even a biggish room.

Now look at the temperature difference between indoors and outdoors and rework the calculations.
On a chilly day 0ºC (outdoors) you'll want the room to be 22ºC (indoors) and that 4 bar electric fire will be running full tilt.
On a hot day say 30ºC outdoors you'll still want 22ºC indoors and that 4Kw of cooling will be on tickover.

I know you can see this, but to be plain, one scenario involves a 22 degree increase in temperature while the other example only needs you to cool by 8 degrees.

A here's where an oversized aircon makes you sad.

When you switch it on, you'll get lovely cooling blasts of yummy fresh crisp air for about 20 minutes. It will then turn the compressor off while continuing to blow air around the room.

After a very short time, the humidity level will go through the roof as the cooled air sucks moisture from the surroundings. While not a technical term, the word 'clammy' is useful. In technical it is called 'Short cycling'. The air may be technically cool, it just won't feel nice.

So what you actually want is the smallest rated aircon unit with a view to it running as close to 100% of the time as you can manage. In this scenario, the unit is continually sucking water from the air and despite the actual temperature, it's going to feel nice. It's easy in Texas, but keeping a building comfortable and cool in a more temperate enviroment is more tricky than you would expect.

Thankfully, modern technology has the answer in the form of the Inverter based aircon.

Rather than run the compressor on a 100%/0% off cycle, you use a variable speed compressor and to ensure that at no point does the A/C stop removing water from the air.

A 1Kw inverter should be more than enough for the average UK sized room.

You can also buy some pretty neat little units that require no more than two four inch holes drilled in the wall - No outdoor unit required and they can be fitted by anyone with a big drill.

As a final point, some tradespeople thing A/C is a cool thing and charge through the nose. A split Fujitsu sytem should cost about £700 retail and the fitting should not cost £1500, more like £300. It's just some plumbing and some gas, nothing that difficult.

Please ask, I'm not qualified to answer the really tricky stuff but I know enough to help out.

Regards,

B.

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Re: Advice on connecting an air conditioner

#218372

Postby gryffron » April 30th, 2019, 10:03 am

Thanks PrincessB. That's really useful to know. What system would you recommend for a largish UK bedroom? They seem to start at 2.5kW. Presumably such a smaller unit would easily run off a socket.

I currently have one of those plug-in, pipe-out-the-window portable units. It is very noisy and horribly inefficient, but still makes the bedroom tolerable on hot sticky nights and I wouldn't be without it. But I have long considered having a "proper" aircon unit in the bedroom.

Gyff

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Re: Advice on connecting an air conditioner

#218435

Postby Howard » April 30th, 2019, 12:42 pm

PrincessB wrote:
am considering having two split wall air-conditioning units installed. They will be powered by a unit such as this http://www.mhiae.com/en/SCM40ZM-S Each installer who has quoted for this job tells me that they will not be too expensive to run in the summer and can be used for top-up heating in the winter if necessary.


Arghh!!!!

These are completely wrong for the UK and you will hate them.


So what you actually want is the smallest rated aircon unit with a view to it running as close to 100% of the time as you can manage. In this scenario, the unit is continually sucking water from the air and despite the actual temperature, it's going to feel nice. It's easy in Texas, but keeping a building comfortable and cool in a more temperate enviroment is more tricky than you would expect.

Thankfully, modern technology has the answer in the form of the Inverter based aircon.

Rather than run the compressor on a 100%/0% off cycle, you use a variable speed compressor and to ensure that at no point does the A/C stop removing water from the air.

A 1Kw inverter should be more than enough for the average UK sized room.

You can also buy some pretty neat little units that require no more than two four inch holes drilled in the wall - No outdoor unit required and they can be fitted by anyone with a big drill.

As a final point, some tradespeople thing A/C is a cool thing and charge through the nose. A split Fujitsu sytem should cost about £700 retail and the fitting should not cost £1500, more like £300. It's just some plumbing and some gas, nothing that difficult.

Please ask, I'm not qualified to answer the really tricky stuff but I know enough to help out.

Regards,

B.


PrincessB

Many thanks for your comments. It is so useful to have a counter viewpoint.

I have tried natural ventilation but we live in the country near water and with the windows open in Summer we get lots of insects coming in and if the lights are turned on for just a minute, mosquitoes queue up to get in and plague me at 3.00 am as well as the next week scratching the bites! I've tried plug-in chemical heaters (ugh) and electronic zappers and they are no good. I've screened the windows, but this cuts down the air flow on a warm night and even with an efficient fan the room is too hot. One of the reasons is that the pipes from the boiler go under the bedroom floor and even though the system turns off well before bedtime the residual heat is there - don't even suggest taking up floorboards and re-routing the pipes!!

I bought a "portable" aircon a couple of years ago and, when it is running it is vented through a frame in the window. It does a very good job of reducing the temperature and apparent humidity in the bedroom in about 20 minutes and makes it very pleasant to go to bed on a hot evening. But it is so noisy that it's unpleasant to consider running in the night. However its performance, and the experience of staying in hotels in the UK retro-fitted with wall aircon units have persuaded me that it is worth having a quiet system which can be set to go on a couple of times while we are asleep.

The "neat little units" you refer to with massive wall vents, in my experience looking at them in the showroom, are not little. They are big and noisy compared to a split wall unit.

I have had conversations with several installers. The reason for the higher installation cost is that for aesthetic reasons the pipes to the bedroom have to go through a route to the bedroom which adds a bit of complexity and no pipework will be visible in either room. And I'm told the commissioning of the twin system will take three hours after everything is installed. I can't believe that anyone would offer to do it for £300 to the standard I'm expecting. Yes my dentist has a horrible unit slapped on the wall with pipes and boxes next to it and I could believe it was very cheap to install but I'm expecting something nicer than that.

When I look at the Fujistu units you suggest, for two wall units and an exterior unit, the basic costs are more than £1,000 not including base and pipes etc and extra for a wifi control. But maybe I'm missing something?

Would very much like to read your further comments if you have time, as I will put them to the installer I choose and will report back on my experience.

Your feedback is appreciated.

regards

Howard

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Re: Advice on connecting an air conditioner

#218481

Postby PrincessB » April 30th, 2019, 3:55 pm

Hi Howard,

Arghh!!!!

These are completely wrong for the UK and you will hate them.


My sincere apologies, I did mention that I was in a hurry, so I didn't digest the whole thread, or look at your link properly.

You're looking at a single outdoor unit and two indoor units with an inverter which at first glance looks ideal - I take the point that there's a lot of plumbing to link all of these together so the quote for installation becomes more reasonable.

To pick up on some other points.

with the windows open in Summer we get lots of insects coming in and if the lights are turned on for just a minute, mosquitoes queue up to get in and plague me at 3.00 am as well as the next week scratching the bites! I've tried plug-in chemical heaters (ugh) and electronic zappers and they are no good.


According to my #1Daughter, mozzies are not attracted to the UV lights on bug zappers, they home in on the carbon dioxide in breath which makes them a bit trickier to deal with than flies. Having been bitten to bits in the South of France last year, I completely understand your situation.

I bought a "portable" aircon a couple of years ago and, when it is running it is vented through a frame in the window. It does a very good job of reducing the temperature and apparent humidity in the bedroom in about 20 minutes and makes it very pleasant to go to bed on a hot evening. But it is so noisy that it's unpleasant to consider running in the night. However its performance, and the experience of staying in hotels in the UK retro-fitted with wall aircon units have persuaded me that it is worth having a quiet system which can be set to go on a couple of times while we are asleep.


I'll assume that your portable aircon is the tall box shaped unit with a single vent hose to exhaust the hot air. I've had these in the past and while they do work, the power efficiency is awful and they make a racket.

For reasons, I don't fully understand, my current house (an elderly Victorian cottage) gets really hot, but for some reason not uncomfortable in hot weather - My old flat was awful to sleep in during summer hence the portable unit I had - My strategy was to turn it on very early in the evening to get as much heat out of the bedroom as I could and then sleep with windows shut and aircon off relying on the greatly cooled room to not warm up to much overnight.

The "neat little units" you refer to with massive wall vents, in my experience looking at them in the showroom, are not little. They are big and noisy compared to a split wall unit.


We may well be looking at different products and if you can ignore the price (which is retail) I was thinking of something like this:

https://www.orionairsales.co.uk/powrmat ... 7498-p.asp

If you look up the PDF, it's appears fairly quiet.

To me, that looks like a nice bit of kit. Even at full retail, you could have a couple of those for £4k. I'd guess at least 50% markup so there's haggle room and you don't need to be qualified to fit one.

When I look at the Fujistu units you suggest, for two wall units and an exterior unit, the basic costs are more than £1,000 not including base and pipes etc and extra for a wifi control. But maybe I'm missing something?

Would very much like to read your further comments if you have time, as I will put them to the installer I choose and will report back on my experience.


It's the wrong time of year to buy this sort of stuff, so prices are high, once we get past the summer, contractors will be offering all sorts of deals to clear stock out.

My view has always been to have discrete units when possible - It's much simpler, I'd understand a single outdoor unit if it were serving lots of indoor units, two adds expense and complexity to the system for less gain.

I will maintain that airconditioning equipment in the UK is massively overpriced for what is essientially a big fridge motor and some pipes. And then there's the amount of use you'll get out of it - For some it might be a big outlay for a few months use each year, for others it is a minor outlay.

Personally, I'd be inclined towards the type of unit the Pwrmatic offers installed in the bedroom. Assuming the bedroom is upstairs, the dehumidification effect coupled with the drift of cooler air down the stairs will help in the living area and the bedroom will be crisp and cool.

If you require further cooling for the living areas, you could suffer the summer and get some more quotes in October, they are unlikely to be more expensive unless we do something Brexit based and collapse the price of the pound.

Regards,

B.

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Re: Advice on connecting an air conditioner

#218509

Postby Howard » April 30th, 2019, 5:58 pm

[quote="PrincessB":[expletive deleted]]Hi Howard,


[quote:[expletive deleted]]The "neat little units" you refer to with massive wall vents, in my experience looking at them in the showroom, are not little. They are big and noisy compared to a split wall unit.[/quote:[expletive deleted]]

We may well be looking at different products and if you can ignore the price (which is retail) I was thinking of something like this:

https://www.orionairsales.co.uk/powrmat ... 7498-p.asp

If you look up the PDF, it's appears fairly quiet.

To me, that looks like a nice bit of kit. Even at full retail, you could have a couple of those for £4k. I'd guess at least 50% markup so there's haggle room and you don't need to be qualified to fit one.

My view has always been to have discrete units when possible - It's much simpler, I'd understand a single outdoor unit if it were serving lots of indoor units, two adds expense and complexity to the system for less gain.

Personally, I'd be inclined towards the type of unit the Pwrmatic offers installed in the bedroom. Assuming the bedroom is upstairs, the dehumidification effect coupled with the drift of cooler air down the stairs will help in the living area and the bedroom will be crisp and cool.

Regards,

B.[/quote:[expletive deleted]]

PrincessB Thank you for the further comments.

I have looked at the powrmatic units in a showroom and they are noisier than split wall units. They are also fairly bulky and take up floor space. That is the reason I have rejected them.

However, you will be pleased to hear that the installer who visited today made a rather unexpected suggestion which fits with some of your comments above. For me as a layman, it didn't immediately sound sensible, but you may agree with his logic.

To avoid the rather complicated, labour-intensive plumbing route to get to the bedroom from the multi exterior unit next to the ground floor room, he suggested fitting two completely individual systems. He said they will be cheaper than one multi outdoor unit serving two internal units.

To start with he wanted to hang one of the exterior units at first floor level which definitely wasn't on! But then he agreed it will fit nicely on the ground in an unobtrusive spot. So his solution is two lower-priced, easier to fit systems. And the fitting in the bedroom will be much neater as all the pipework will run inside a fitted wardrobe. The external pipework will run down the wall virtually hidden behind an existing down pipe from the gutter. Even better, with two lower power systems, each can be connected to different circuits on the 13 amp ring main.

So, I hope you think this might meet some of your criticisms. We'll see how the quote turns out.

One unarguable lesson from this is that it is worth getting a number of quotes because as the customer, one learns a bit more each time and can guide the professional. Oh! And the value of Lemon Fool is that one gets unbiased advice as well.

Thanks all for your comments - watch this space if you are interested in aircon - I'll keep you posted.

regards

Howard

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Re: Advice on connecting an air conditioner

#218751

Postby PrincessB » May 1st, 2019, 3:43 pm

To avoid the rather complicated, labour-intensive plumbing route to get to the bedroom from the multi exterior unit next to the ground floor room, he suggested fitting two completely individual systems. He said they will be cheaper than one multi outdoor unit serving two internal units.


Hi Howard,

Thanks for being so polite and thoughtful with your responses.

I will second that idea without hesitation.

So his solution is two lower-priced, easier to fit systems.


It's been a long time since did this. By my out of date knowledge, Fujitsu were the budget choice, Daikin (I think) were part of Mistsubishi, great kit but many of their products are designed for more complex needs than you have.

There are some self fit units which come with pre-charged hoses, I'm not sure if this is what he's thinking when he says 'easier to fit systems'. Personally I'd draw the line at Fujitsu and if you don't know the brand name, beware.

You could also ask about the positioning of the water drains to get a better idea of how competent the installer is. One of the proposed outdoor units is next to a downpipe, so an easy solve. What about the other one?

The amount of water these things can pull from the air can be interesting. My old Qualitair wall mounted unit (2.6kw compressor 250watt fan) used to condense sufficient moisture to dribble like a slow running tap. There was a drain nearby so it was not an issue for me. I doubt you would want a few litres of water pooling outside so do ask.

Regards,

B.

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Re: Advice on connecting an air conditioner

#218928

Postby Howard » May 2nd, 2019, 11:36 am

Thanks PrincessB for your further comments.

Here is a progress report as I get to the decision stage.

Itsallaguess, you asked for a detailed review, hopefully this covers the subject.

I have rejected the idea of two larger Powrmatic wall units. Easy to fit but take up too much wall space at low level, cost more than £3k to buy before fitting, require four large 4 inch diameter holes to be punched through the wall with ugly external vents and at 27 dB(A) noisier than the lower three of the four speed settings on a Mitsibushi split wall unit.

Four contractors have quoted for split systems and the brands include LG, Panasonic, Daikin and Mitsubishi. One quote would work out over £5k and the others are around £2.5 -3k including 5% VAT.

Despite the information I reported in an earlier post, when I received the quote, the cost of fitting two separate systems was not cheaper than two wall units connected to one inverter. The plumbing is simpler but do I want two large inverters in my garden?

I’m now choosing the best location for a single multi inverter and have noted PrincessB’s helpful comment about the importance of the drain connection to a downpipe. The (bulky) external inverter will be sited where it will not be heard by neighbours (nor me!) and won’t be an eyesore when sitting in the garden. Virtually all of the plumbing will be hidden.

I know this is just a “paper” excercise, but when I summarised all the quote features which interested me on a spreadsheet table, Mitsubishi Heavy Industries wall units look the best solution for me. Its wall unit's lowest two fan settings are very quiet - 19 and 22 dB(A).

The installation will require an annual service to qualify for a 5 year guarantee so I have found out the costs of this (around £100pa) and will get this in writing as this is a running cost. The final factor is the electrical connection. I have an estimate for fitting a 16 amp spur but three contractors have told me that it is a domestic installation and they will connect to a 13 amp supply which will not affect the guarantee.

I’m not sure if I’ll use the WiFi facility much, but will be able to programme the unit from my phone.

Hope this summary is helpful. I’m sure it would be possible to cut the installation cost by ignoring the aesthetics and having exposed pipework but I doubt it would save more than a few hundred as it is a two day job. I’m not expecting to sell my house, but if I did, and the new owner hated the aircon, it could be easily removed with hardly a trace. Or the hidden plumbing will allow the installation of an even better, cleaner system in 10 years time.

Will report further after installation.

regards

Howard

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Re: Advice on connecting an air conditioner

#222449

Postby Howard » May 17th, 2019, 12:22 pm

Itsallaguess wrote:
Just out of interest Howard, have you got a link to show us which internal units you're planning to use?

Also, as well as the above, are you able to itemise your quotes for each bit of kit, and also installation costs?

I only ask because this type of air-conditioning installation has piqued my interest in the past, so to have someone on the verge of installation, presumably having done some prior investigation work, is very timely.

Cheers,

Itsallaguess


The aircon was installed over a week ago and I’m very pleased with the outcome.

Two fitters worked for a day and virtually completed a fairly complicated installation in that time. Because of the internal structure of a (virtually inaccessible) single storey loft the exterior pipework had to be installed in a slightly different configuration than initially planned. This meant that a final piece of the exterior ducting was fitted in a few minutes on day two.

The end result is aesthetically very satisfactory. As some readers will know, when one commissions a job like this, for a few weeks, one notices aircon installations everywhere you go. The dentist and the doctors’ surgeries and even looking out of the window of the gents in a London restaurant! Most commercial installations look awful! Internal trunking, pipes and boxes on the wall and the exterior inverters are not things of beauty.

Our wall units are not that obtrusive and all services enter from behind the wall so are invisible from inside. Outside the house, the trunking is close to perfect with just one run down the wall, matching a white downpipe from the gutter. I am in the process of hiding the inverter behind a frame which will act as a table next to my bbq. It will not restrict the airflow but will almost hide the unit. The system was connected through the wall to a 13 amp plug.

I’m pleased with the choice of Mitsubishi Heavy Industries, premier, wall units (See the link in earlier post). They are smaller than Daikin units and offer all the facilities we need. In the end I didn’t include Wifi modules as they didn’t offer me any advantage over the very comprehensive timer facilities included with the wall units. Ok I can’t control the aircon from the car nor from New York, nor can Alexa turn it on, but that isn’t important to our lifestyle.

What is important is that the aircon in both cooling and heating mode is amazingly quiet and effective in operation, both inside and outside. There are four speed settings and whilst the weather hasn’t been hot enough to test the aircon for a long period, I doubt if we will ever use more than the lowest two settings. They are inaudible when watching TV and barely noticeable in a totally quiet bedroom on a still day in the country when only birdsong can be heard outside.

The cost turned out to be £2,300 and the installers were first class. I’ve given them top ratings on Checkatrade.

Hope this is helpful to you and anyone considering this type of project.

regards

Howard

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Re: Advice on connecting an air conditioner

#222486

Postby Itsallaguess » May 17th, 2019, 2:55 pm

Howard wrote:
I’m pleased with the choice of Mitsubishi Heavy Industries, premier, wall units (See the link in earlier post). They are smaller than Daikin units and offer all the facilities we need. In the end I didn’t include Wifi modules as they didn’t offer me any advantage over the very comprehensive timer facilities included with the wall units. Ok I can’t control the aircon from the car nor from New York, nor can Alexa turn it on, but that isn’t important to our lifestyle.

What is important is that the aircon in both cooling and heating mode is amazingly quiet and effective in operation, both inside and outside. There are four speed settings and whilst the weather hasn’t been hot enough to test the aircon for a long period, I doubt if we will ever use more than the lowest two settings. They are inaudible when watching TV and barely noticeable in a totally quiet bedroom on a still day in the country when only birdsong can be heard outside.

The cost turned out to be £2,300 and the installers were first class. I’ve given them top ratings on Checkatrade.


Great write-up Howards, and I'm pleased to hear that everything went smoothly and you've been left with an installation that both delivers on it's original intent, and is as unobtrusive both inside and outside as you'd hoped it might be.

I know you've mentioned earlier links to the main components that you eventually had installed, but for completeness are you please able to repeat those links, both for the external and internal units?

Cheers,

Itsallaguess

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Re: Advice on connecting an air conditioner

#222490

Postby Howard » May 17th, 2019, 3:26 pm

Itsallaguess wrote:
I know you've mentioned earlier links to the main components that you eventually had installed, but for completeness are you please able to repeat those links, both for the external and internal units?

Cheers,

Itsallaguess


I don't know which supplier my installer used, but the advert below shows the multi unit which was installed. So it's one inverter attached to two wall units. He emphasised that it is worth paying a little extra for the Premier wall units, as shown. They apparently look better than the basic units.

I've shown the advert, because it goes some way to addressing your initial request of breaking down the cost of the units and fitting. I would guess you would have to add £300 - £500 to the basic cost of £1,113 to include the full kit which was used for the installation. For example, chatting to the installer on day two, the cost of just the extra plastic ducting elbow which was fitted later was £18 and that was the reason they didn't carry it on their van. The ducting they used was very neat and, I guess wasn't cheap.

As an observer of the installation and testing, I wouldn't be tempted to go for a "cheapo" fit. I was very happy to pay around £1k for the expert fitting.

regards

Howard

https://www.saturnsales.co.uk/Mitsubish ... 7KEALw_wcB

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Re: Advice on connecting an air conditioner

#222495

Postby Itsallaguess » May 17th, 2019, 3:51 pm

Howard wrote:
I don't know which supplier my installer used, but the advert below shows the multi unit which was installed. So it's one inverter attached to two wall units. He emphasised that it is worth paying a little extra for the Premier wall units, as shown. They apparently look better than the basic units.

I've shown the advert, because it goes some way to addressing your initial request of breaking down the cost of the units and fitting. I would guess you would have to add £300 - £500 to the basic cost of £1,113 to include the full kit which was used for the installation. For example, chatting to the installer on day two, the cost of just the extra plastic ducting elbow which was fitted later was £18 and that was the reason they didn't carry it on their van. The ducting they used was very neat and, I guess wasn't cheap.

https://www.saturnsales.co.uk/Mitsubish ... 7KEALw_wcB


Brilliant - thanks very much Howard.

I'm sure I won't be the only one interested in an interim report later in the summer...

Cheers,

Itsallaguess

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Re: Advice on connecting an air conditioner

#222522

Postby PrincessB » May 17th, 2019, 5:24 pm

I'm sure I won't be the only one interested in an interim report later in the summer...


Well there goes our chances for a hot summer :?

At least with a reversible system that both heats and cools, Howard can let us know how it works in heating mode during August!

True story from last year,

I was finding it very hot in my South West facing kitchen which has a lot of sun facing glass, as well as a lots of big Velux windows. Indoor temperatures were in the high 30ºC's with the windows and roof lights open.

I deal with a company who were having a refit, and in a skip were some massive fan units - Proper huge industrial fans, the kind that hang high up on chains with louvres to direct the airflow downwards. With permission, I acquired two of them, each just liftable, took one home and gave the other to a mechanic was also complaining about the heat when my scooter was in for a service.

The plan was for him to use the fan in the way it was designed, hang it high up in the workshop to jet air around. Mine was to mount it on some wheels and park it outside the kitchen door with a view towards blasting the cooler evening air into the house once the sun was down.

We had a look at them in the workshop and established that the fan motors were rated at 800Watts and despite being pulled out of a skip the connections were included so all we needed to do was run up a couple of cables to see if they worked.

And that's when the Summer heatwave of 2018 ended, the temperature dropped by at least 10ºC overnight and my fan sits in a corner of the garage unused while the mechanic's one got thrown into a skip when he relocated his workshop.

My tongue in cheek prediction is that the average temperture in the UK in general are now going to be stuck at 18ºC until at least 2021 so the run time of these units is going to be measured in minutes rather than hours.

B.

Thanks for the excellent updates and links Howard, I'm sure we'll have the odd warm day between now and November.


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