Split air-con

doggles

doggles

doggles

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Southampton
so... it's hot

I'm sweaty and my wife's grumpy...

So have you had a split air con system installed, before I start getting people round I wanted some idea of costs. I've had a google and can see the general price of units. So I'm looking for an idea of installation costs really or how much it all cost you.

Any advice appreciated

Cheers!
 
Depends how many rooms size of house position of the external
Kit.

Really in this country it is a terrible use of the worlds limited energy resources.
 
There is a active thread over at pistonheads on this. https://www.pistonheads.com/gassing/topic.asp?h=0&f=207&t=1675072

I don't quite get why it is so expensive to install split air con in this country. Someone in that thread said it cost them £10k which is frankly ridiculous amount to spend for a few warm nights. I'd love to see a breakdown of labour costs for it, as we can all see the split units aren't excessively expensive on their own.
 
Trifid said:
There is a active thread over at pistonheads on this. https://www.pistonheads.com/gassing/topic.asp?h=0&f=207&t=1675072

I don't quite get why it is so expensive to install split air con in this country. Someone in that thread said it cost them £10k which is frankly ridiculous amount to spend for a few warm nights. I'd love to see a breakdown of labour costs for it, as we can all see the split units aren't excessively expensive on their own.
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Small market do installers can take the P, you are right 10k is madness in the UK unless that sort of money is easy for you to drop! Get a ceiling fan and save 9.9k
 
It's like to be three rooms bedrooms basically. I saw you can get pre-gassed units & hoses.

After looking around there seems a relatively high variety of prices. Guess I'll bite the bullet and give some installers a shout and go from there See what they quote & decide if I wanted to pay that
 
doggles said:
It's like to be three rooms bedrooms basically. I saw you can get pre-gassed units & hoses.

After looking around there seems a relatively high variety of prices. Guess I'll bite the bullet and give some installers a shout and go from there See what they quote & decide if I wanted to pay that
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Have you considered/tried a ceiling fan?
 
Also ceiling fans don't warm the rooms in winter.

AC will.

And saves running house central heating to only warm one or two rooms.

Next point would be are you looking at separate split air for each room or a central system with one outdoor unit and separate indoor units in each bedroom?

Separate systems for each room are easier and cheaper to do, but then you gave to find room for three outdoor units.

Central AC is more aesthetic with only one outdoor unit but far costlier and complicated to install.

As for instalation, you get loads of cowboys who will say we can do that, will be one day all sorted.

That is a blatant corner cut and will result in a bad system.

A competent qualified installer doing it to regulations will take 2 to 3 days to fit one room split air, a central unit for multiple rooms you are looking at a week's work really, to do it correctly to all regulations.
 
Entai said:
Also ceiling fans don't warm the rooms in winter.

AC will.

And saves running house central heating to only warm one or two rooms.

Next point would be are you looking at separate split air for each room or a central system with one outdoor unit and separate indoor units in each bedroom?

Separate systems for each room are easier and cheaper to do, but then you gave to find room for three outdoor units.

Central AC is more aesthetic with only one outdoor unit but far costlier and complicated to install.

As for instalation, you get loads of cowboys who will say we can do that, will be one day all sorted.

That is a blatant corner cut and will result in a bad system.

A competent qualified installer doing it to regulations will take 2 to 3 days to fit one room split air, a central unit for multiple rooms you are looking at a week's work really, to do it correctly to all regulations.
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Thanks very informative and helpful
 
Just be very careful and double/triple check warranty conditions on self fit units.
Most of the time you will get 1 year on parts but not on installation.

The issue with all self fit units is that YOU WILL get air and moisture into the pipework when you make the connection between indoor and outdoor units.

Air and moisture KILL air con systems there is no two ways about it, that's why competent professional registered installers will pressure test, leak test, and vac out the system before filling with refridgerant to guarantee there is zero air and or moisture in the system.

The kit to do that costs around a grand, and should take in excess of 24 hours, so normal diy'ers do not do that part of the install, come to that many so called " professionals" will rush it and only test and vac for a couple of hours which is not enough and does not comply with any regulations or guidelines.

Not to mention that the liquid used boils off at - 25 degrees C and is pressurised in the system so can cause horrific burns if accidentally released, which is also by the way a criminal offence to release refridgerant into the atmosphere.

Don't cut corners to save a few quid, get it installed by a professional fully F-Gas certified installer (like me) yes it costs a bit more but is safer in the long run and will guarantee a flawless system that will last many years.
 
I did the same with my parents cottage in France, bought a unit locally which had quick couplers on, luckily this were just screwed over normal flare fittings. removed these and did a full pressure test vac.

Got one sitting to install in my house but hate doing split installs, give me a chiller any day!!
 
Split installs have their place and if specced properly do make a very reliable and relatively cheap solution.

I have central air in mine, a five zone system, but as I could buy with big discount and fit for free only cost me about 4k.
 
Entai said:
Just be very careful and double/triple check warranty conditions on self fit units.
Most of the time you will get 1 year on parts but not on installation.

The issue with all self fit units is that YOU WILL get air and moisture into the pipework when you make the connection between indoor and outdoor units.

Air and moisture KILL air con systems there is no two ways about it, that's why competent professional registered installers will pressure test, leak test, and vac out the system before filling with refridgerant to guarantee there is zero air and or moisture in the system.

The kit to do that costs around a grand, and should take in excess of 24 hours, so normal diy'ers do not do that part of the install, come to that many so called " professionals" will rush it and only test and vac for a couple of hours which is not enough and does not comply with any regulations or guidelines.

Not to mention that the liquid used boils off at - 25 degrees C and is pressurised in the system so can cause horrific burns if accidentally released, which is also by the way a criminal offence to release refridgerant into the atmosphere.

Don't cut corners to save a few quid, get it installed by a professional fully F-Gas certified installer (like me) yes it costs a bit more but is safer in the long run and will guarantee a flawless system that will last many years.
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Whilst I agree with most of what you've said you are exaggerating this a bit! The equipment is not into the thousands, you require nitrogen with regulator and line for pressure testing and then a vacuum pump, not even gauges are required if you vac for 24hours. (before you say it I know that other kit exists and should be used, vac gauges etc) The regulations are 15 minutes strength testing and then a further 1 hour minimum for tightness testing. Vacuum requirements are to 2 Torr which in a small new system with new pipework will be achievable in 1 hour unless you have a leak - which you shouldn't! To shine more light on to this Marstair actually state in their installation manuals that pressure testing it not required and a vac to 2 Torr is all that they require - you will know if you have a leak as the system will not pull a vacuum or it will rise etc. So hardly 24 hours!
Sure the issue with the self install kits will be moisture and potential leaks which are a direct result of lack of pressure testing and vac but the real argument here is the quality of the kit you get at that price point. Prices soon start shooting up when you look at a decent inverter split unit from the likes of Mitsubishi Electric (not heavy industries) such as the P series. You'll also find that unless this kit is installed and then maintained by a qualified engineer the the warranty will be out of the window.
Decent companies will only quote of the equipment that they believe in, which IMHO Panasonic are junk, but they also get extended warranties. Eg Toshiba are now doing 7 year warranties to engineers who have taken their free courses.

2 days is a good estimation for labour to install to a good standard. So many factors are involved with a domestic house, one big one being the pipe run. Its like most things, cheap systems installed in the worse way possible can and do work and some last for ages without being serviced, but if they dont - I would expect the parts to be so expensive that it outweighs any repairs and the likely hood of those fault to crop up are increased 100%, warranty with those systems? Doubt that...
It actually more concerning that the systems are available to the general public - you cant acquire refrigerent from the wholesalers without being F Gas registered so how you can get a pre charged system without is beyond me.

FYI I am Mitsubishi electric certified installer. F Gas and C&G guilds qualified.
 
I said around a grand, and yes maybe a slight exaggeration, but as you know any decent vac unit will set you back approx £500+ on its own, and then add in the other bits, lines, gauges, leak detectors, etc and you are not far short

Have another read of the 'Code of Practice for Refrigerant Leak Tightness in Compliance with F-Gas Regulations', as issued by the British Refrigeration Association, and also the current actual BSI regulations BS EN 378-1:2016 (updated Dec 2016) they state quite clearly, that for a tightness test the test pressure duration is 24 hours recommended, with a minimum of 6 hours.

Also yes the regulations say Vac to 2 Torr but we all know that any half competent installer will go to at the very least 1 Torr, and most likely if you wish to do your job properly, you would want to be seeing 1/2 Torr or 500 microns ideally, or as damn close to that as you can get, and you would want to see it stable at at that, not fluctuating at all.

Talking of which I have seen a couple of self fit split systems, that get to around 1.0 Torr and appear stable after about half an hour, but after few more mins start to fluctuate, going up to 1.2 and back down to 0.85 then up and down more, this is the moisture boiling off within the system, because of (I can only assume) the poor manufacture and assembly at the factory, and you must wait for that to stabilise before you stop the vac and fill with liquid, so I will vac for minimum 3 hours on any split system, and as I say, really until I see a stable gauge.

Slight aside but I work mainly with large industrial cascade systems, usually using R23 going down to to -60/-80 degrees plus, so am used to working at the extremes, so I guess my tolerances are tighter, and I carry that attention to detail across to fitting split systems as well.

One system I installed last year was a large two stage cascade, with 60 kilos of R404a in stage one, and had around 80 kilos of R23 in stage 2, somewhere around 1200 metres of pipework within the system, almost 500 brazed or silver soldered joints, had that on tightness test for eight weeks, and then on vac pump for nearly a month before finally reading stable at 0.6 Torr to add the refrigerant, but as I say that is an extreme.
 
Yep, decent kit cost money but you don't need to spend £500+ on a top of the line vacuum pump to vac a cheap basic self install. The point I'm trying to make is that you can still test and vacuum a system for a lot less than what you quoted, you don't 'need' all that listed kit to perform a basic pressure test and vac.

That document is ten years old, lists the incorrect frequencies for leak testing under F Gas, incorrect strength testing pressures (1.3X instead of 1.43x) and the most important bit; tightness testing minimum for 6 hours which has now changed to just 1 hour. The realisation of it being impracticable in most cases to tightness test for a minimum of 6 hours has forced the changes - can you imagine an engineer tightness testing for 6 hours after an on site repair to small equipment and the customer paying for that?! I don't have BS EN 378 to hand so I can't confirm what that says but I have spoken to an F Gas instructor that confirms this.

You're right obviously pressure testing longer is better and also achieving a lower vacuum is preferable and on a correctly installed split system with <15m pipe work will shoot down to below 1 Torr.

Not really sure why you've typed the rest, its completely off topic. I have also worked on cascade systems and they are a different ball game to a self install split.

Back to what I originally started, those cheapo self installs are not the best, the kit is basic and cheaply made good quality kit cost money and thats where the higher quotes come from. You 'could' improve the self install by dehydrating the system (vac pumps are available for £150 that will be capable for this) but I think you would be fighting a loosing battle with reference to the parts used in the first place.
 
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