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View Full Version : Reducing cost of split system Air Con install















Wildman
19th January 2005, 09:01 AM
I recently thought I saw a bargain on Grays Online and bought a new 1.5HP split system airconditioner before finding out the installation costs. I was wondering if anyone had any suggestions for reducing the installation costs. I am happy to mount the unit, "organise" the wiring and run the copper pipes through the walls but dont know if there are any special requirements for aircon copper that I need to be aware of.

I dont particularly want to pay the cost of the air conditioner again to install it. If the missus found out installation was so expensive, I wont hear the end of it.

Are there large benefits from mounting the compressor as remotely as possible or on the ground vs some splits I have seen where the compressor is mounted on the wall outside the internal unit on aluminium brackets. It will be for a bedroom so dont want much compressor noise if possible but dont want to increase the installation costs either.

Does anyone have any aircon "mates" in Melbourne (eastern suburbs) that would install for beer or IT work or both?

Cheers
Ben

LineLefty
19th January 2005, 11:47 AM
A suggestion
Find and buy the copper piping yourself if you intend to use more than the 2m supplied with the unit. The installers charge up to $60 a metre for it!

jimc
19th January 2005, 01:50 PM
Lookup Actrol in Blackburn. They supply the refridgeration/airconditioning industry with all their bit and pieces.

For 1.5hp, it may need its own dedicated circuit due to drawing 15amps - added expense. Check manual closely.

Fat Pat
19th January 2005, 03:35 PM
Wildman, I had a mate instal 2 units at my place, with me providing "Gofer" duties, here are my thoughts on the matter....

1. Read the instruction manual that comes with the unit, it should give you the size of the pipes required. Remember that there are two sizes, one for the "Go" gas, and one for the "Return". If you get the flexible copper pipe, it is pretty simple to route it as you want, the rigid stuff will require gas burner and bending tools. Plus you need pipe flaring tools for the joins etc.

2. You will need pipe insulation to suit the lengths you require.

3. Depending upon power requirements all you may need is a power point adjacent to the head unit (and a single 3-core run to the external unit) or the more complicated (and expensive) fixed install with isolation switch to the external unit. If it is the simple set-up, then anyone can run the power cable, as long as a "Licensed" person does the connections.

4. The instruction manual will give pipe-length guidelines, if you have a longer "throw" then you may need to top-up extra refridgerent, as there may not be sufficient pressure to maintain cooling. Plus a longer run will result in the compressor having to use more of its power to push the gas - leaving less for actual cooling. My 1 HP unit has a 7 metre run each way, and my 3.5 HP unit has about 15 metres in each direction - neither unit has any trouble keeping the place cool (in fact I generally have 10-15 degrees in excess cooling capacity)

5. You can mount the compressor from a rack on a wall, but I don't recommend it, as you can get some funny vibratory type noises coming through the house. Placing the unit a couple of concrete slabs or brick paving is more than adequate. GENERALLY, the units are extremely quiet, much quieter than an equivalent RAC (Box-in-Wall Type)

6. Don't forget the drip pipe. MY 3.5 HP unit throws up to 3 litres of water an hour. so if you don't want your brick paving to turn green, then you'll need to install a proper drain.

A final thought to consider. In Perth (and presumably OZ generally) we have seen stacks of "No-Name" A/C splits advertised for bargain prices. Their problem is that they have very inefficient compressors, so you need to use a lot more power than "Brand Name" units. They may have a 5-Year warranty, but if you use 5 times as much powere, are they really that good a deal.

I recommend Mitsubishi, and I have no affiliation with them. My units work bloody good, and that is all that matters.

Hope that may help you a bit.

Harry72
19th January 2005, 05:10 PM
Lookup Actrol in Blackburn. They supply the refridgeration/airconditioning industry with all their bit and pieces.

For 1.5hp, it may need its own dedicated circuit due to drawing 15amps - added expense. Check manual closely. A 1.5hp shouldnt draw 15amps, a 10amp circuit will power up to a 3hp motor.

nt900
19th January 2005, 08:14 PM
Cannot help, but thought I would share my current situation.<O:p</O:p

Installation is expensive, maybe because of the time of year and maybe it would be cheaper during the cooler months when people think less of purchasing a AC and therefore less work around for installers.<O:p

I want to install a 3 head split system in a house. I prefer the Daiken system which is one of the more efficient, but expensive systems. Costing $4400, Mitsubishi would cost me $2800, others are even cheaper. Regardless of the system components, the installers want $3200 to install the equipment. For my system there is a lot of piping, but nothing especially difficult installing it. Considering I am making the job easy for them by not plastering up areas or removing plaster, and doing everything else to make it easier for them(objective is to make it cheaper for me). But still the ratio of installation to equipment cost is frustratingly high.<O:p

Another comment: When simply asking various companies to supply and install a system (sometimes I specify the equipment or brand I prefer, and sometimes I leave it up to them; I find that some companies do nice quotes where you know exactly what you are going to get, whilst some provide such vague quotes that I could end up with just about anything installed anyhow. Really poor effort, so I would hate to see their work.<O:p

I am up for suggestions or recommendations from anyone out there.

Wildman
20th January 2005, 08:52 AM
Thanks for the feedback.

I am currently trying to source "friends of friends" to do the hookup, I plan to mount the compressor and piping myself. The system wont be used much as it is only in the bedroom and wont be left on at night, basically enough to cool the room to get to sleep so efficiency is not critical. A number of installers will only do supply and install, probably to get the margin on the unit as well as being sure what they have to work with. I have all the gear I need to do the bulk of the work, flaring tools, oxy, cutters benders etc and the AC circuit has already been installed in the fuse box, I just need to run the wiring to wherever the unit requires it. I only need an installer to check for leaks and gas up the system and dont particularly want to spend $500 for one hour's work.

Good point about the drip pipe, I have a nearby Hydrangea that would appreciate a drip feed of water on hot days.

Cheers
Ben

Iain
20th January 2005, 09:22 AM
We have a 2.5hp Hitachi mounted on the wall in line with the internal unit and about 350mm lower. Minimal run of copper and no vibration.
Install took about 3 hours with new circuit into fuse box and vacuum took 30 minutes (actually less but sparky said he always leaves the compressor omn that long while he's doing something else).
3 hours labour + cabling + wall bracket ($60.00) + pretty plastic casing to hide cables and copper, shop around you can get it for a lot less than the $700 odd that a lot of places quote.

jimc
20th January 2005, 05:13 PM
The unit I just had installed new 5.5 star rated 1.5hp inverter unit and it needed a 15amp circuit. Its one of the new splits that uses R410A gas. Thus the need to look at the manual for power rating!

The total installation of unit plus dedicated circuit cost $850 included 4.5 metre run back to the compressor.

Harry72
20th January 2005, 10:41 PM
jimc, you might be right I just checked the kickout switch in the power box for my 3.5 mitsi its running a 32amp circuit! Thats as much as my shed will be running off, when I can get my sparky mate of his ass to finish the job!

Iain
21st January 2005, 08:03 AM
We must both have the same sparky mate, got a circuit breaker and two power points three months ago and still waiting for the full wire and lights :mad:

Fat Pat
21st January 2005, 01:01 PM
Sorry guys, forgot to mention it....

The start-up surge on these units is impressive. When I first fired my 3.5 HP unit up, the start current peaked around 25-30 amps!

That's why you have a 32 amp breaker....

Termite
21st January 2005, 01:18 PM
12 months ago had a 3hp Daikin split system installed. Dedicated 30amp circuit with powerbox at one corner of house and unit at the diagonal corner (long run). 5Metre piping, total install cost $500.00. This is a pretty standard charge in our area, so watch out for the bloody burglars out there.

tcns
21st January 2005, 08:00 PM
A 1.5hp shouldnt draw 15amps, a 10amp circuit will power up to a 3hp motor.Most 1.5Hp draw about 4a flatout, some even come with 3 pin plugs
on them so they can be plugged in.

A far classier way to do it is to get a sparky to pull the line through into the roof or wall and jumper it up with a new circuit.

To make an install cheaper do 90% of it yourself. I did all mine myself and paid a bloke to come and vac out the system and test it all up, check my work and sign the warranty card.

Mount up the internal unit first, cut the holes and attach the base plate the wall mount up the internal unit and feed the copper lines through. Buy an install kit with pipes in it from an AC supplier which has the longer pipes in it with the ends already flared etc.

Mount the outoor unit so it looks nice, mine is attached to the brick base of the house with brackets from the AC supplier, no vibrations all good.

Run the connecting electrial cable to the outdoor unit, ask the ac bloke to fix it up for you - in all honesty 240V wiring on terminal blocks like that are the most half assed thing I have seen, most installers don't crimp the ends they just strip the wires back and wind them together. The wiring I put in my car is 100 times safer and better designed/setup/executed.

Here is the breakdown of my cost.

Air Con unit 1.5 HP split system $499
Brackets $ 45
Plasterboard anchors $15
Pipe covering $80
AC bloke to come out and commission $88

Total $727

Cheapest install quote was $450+gst

Just ring around the installers and find out someone who will come out and have a look, vac it out and sign off on it, that might be a bit tricky but I found a crowd that were happy to do it

Tom

TheDad
22nd January 2005, 12:33 AM
as i sit in almost 40 degree heat at midnight I drool at this post.


ahhh cool air, but where to place one? in the lounge room, in our bedroom, in the kitchen????


to many unanswered questions. i now must sleep


if I can

nt900
22nd January 2005, 09:00 AM
Multi (3) head split system.....done.....go to sleep now.

jolybean
20th January 2006, 10:55 PM
Wildman, I had a mate instal 2 units at my place, with me providing "Gofer" duties, here are my thoughts on the matter....

1. Read the instruction manual that comes with the unit, it should give you the size of the pipes required. Remember that there are two sizes, one for the "Go" gas, and one for the "Return". If you get the flexible copper pipe, it is pretty simple to route it as you want, the rigid stuff will require gas burner and bending tools. Plus you need pipe flaring tools for the joins etc.

2. You will need pipe insulation to suit the lengths you require.

3. Depending upon power requirements all you may need is a power point adjacent to the head unit (and a single 3-core run to the external unit) or the more complicated (and expensive) fixed install with isolation switch to the external unit. If it is the simple set-up, then anyone can run the power cable, as long as a "Licensed" person does the connections.

4. The instruction manual will give pipe-length guidelines, if you have a longer "throw" then you may need to top-up extra refridgerent, as there may not be sufficient pressure to maintain cooling. Plus a longer run will result in the compressor having to use more of its power to push the gas - leaving less for actual cooling. My 1 HP unit has a 7 metre run each way, and my 3.5 HP unit has about 15 metres in each direction - neither unit has any trouble keeping the place cool (in fact I generally have 10-15 degrees in excess cooling capacity)

5. You can mount the compressor from a rack on a wall, but I don't recommend it, as you can get some funny vibratory type noises coming through the house. Placing the unit a couple of concrete slabs or brick paving is more than adequate. GENERALLY, the units are extremely quiet, much quieter than an equivalent RAC (Box-in-Wall Type)

6. Don't forget the drip pipe. MY 3.5 HP unit throws up to 3 litres of water an hour. so if you don't want your brick paving to turn green, then you'll need to install a proper drain.

A final thought to consider. In Perth (and presumably OZ generally) we have seen stacks of "No-Name" A/C splits advertised for bargain prices. Their problem is that they have very inefficient compressors, so you need to use a lot more power than "Brand Name" units. They may have a 5-Year warranty, but if you use 5 times as much powere, are they really that good a deal.

I recommend Mitsubishi, and I have no affiliation with them. My units work bloody good, and that is all that matters.

Hope that may help you a bit.
Pls let me know which pipe is the "go" , is it the bigger one ? in my installation manual they call them " gas" and "liqid" pipe so pls explain for me.

Dan_574
20th January 2006, 11:05 PM
3.5hp Airwell system installed for $650 that I bought from Harvey Norman, I was thinking of doing just what you guys are mentioning about doing most of it yourselves. Thank god I didnt because a month after it went in I had to get the whole unit replaced because of faulty pipes in the head unit. If I had of done it myself I wouldnt have been covered by warranty because it must be installed by a qualified installer.

Markw
23rd January 2006, 10:25 AM
Pls let me know which pipe is the "go" , is it the bigger one ? in my installation manual they call them " gas" and "liqid" pipe so pls explain for me.

In A/C systems on cars, the liquid pipe is always the smaller pipe (compressed gas as a liquid to the TX valve), whilst the gas return pipe (liquid back to gas from evaporator) is the larger pipe. In recent made vehicles they quite often use the same diameter hard piping for both, probably to save the few cents in manufacture.

But then again if you have to ask which is which, then your understanding of this complex piece of machinery may not be sufficient to do the install. Maybe you should get it installed by a professional.

tcns
23rd January 2006, 11:04 AM
3.5hp Airwell system installed for $650 that I bought from Harvey Norman, I was thinking of doing just what you guys are mentioning about doing most of it yourselves. Thank god I didnt because a month after it went in I had to get the whole unit replaced because of faulty pipes in the head unit. If I had of done it myself I wouldnt have been covered by warranty because it must be installed by a qualified installer.

Dan,

Read the posts above mate - I have my warranty card signed so mine has been installed by a professional. Just because I did the grunt work myself doesn't make ANY difference i.e. Mount the inside and outside units run the pipes and wiring and have it finished off by a fridgie and sparky.
Read the whole thread before you have a bit of a sledge

Faulty pipes in the head unit ususally mean old mate the installer has overtightened them and caused the fixed copper pipe in the head unit to fail.

Tom

Dan_574
23rd January 2006, 05:14 PM
hey tcns I cant see where Im having a sledge, far from it just making people aware of the dangers of not getting it done properly, if yours was signed off well and good.

tban
13th March 2006, 07:10 PM
Just had one 3.5 and two 1HP units installed. Done for $360 each, I'm told the standard price would have been $500 each. Reduction due to electrics; already had a 32 amp circuit in place for the big fella (replacing a weatherwall unit), and 'conveniently located GPO's' on a standard 16 amp circuit for the two 1HP's. Suspect that it might cause some grief if both the 1HP's were started up at the same time, but once running they live happily enough on the same circuit.

Could have saved more by mounting the internal units. Just read the manual and make sure you have the clearances around the unit, and locate it so that it's in (vertical) line with the 'desired' location of the external unit. If you do it yourself you can spend some time thinking about where the vents will blow. To mount the internal unit you (generally) drill a steel plate to the wall (five or six light duty plugs seem to do ok). Then you need a hole through the wall. The manual will indicate where (generally you get a choice of left or right). My guy just buzzed a circle of 6 or 7 holes through with a 15mm or so masonry drill, and then hammered out the waste. Did the inside first, then the outside (double brick) working back in. A bit of thought should ensure the holes line up (dipping slightly towards the exterior, say 10mm). I could easily have done as good (in fact better) job than the air con guy. It looked like his least favourite part of the job.

Pull the unit back off the wall (leave the wall plate) and at that point call in the air conditioning guy. If he's dubious (or if you're dubious) about the quality of the work, tell him that there used to be a unit in the same location (but clear up the brick rubble before he arrives). He probably knows that you know that he knows it's a 'bodgy job', but everyone saves face. Ultimately the hole was about 60mm diameter. Should be large enough to take the pipe 'cluster' that's fitted to the back of the internal unit. Theoretically the hole through the wall should be sleeved, but I didn't see this done.

In WA any further work (eg pipework) would be running close to the wind in terms of regulation, they've got a bit more antsy with airconditioning gas issue. For the amount of work involved in pipe bending and flaring (I've got the tools) I figured paying $280-$300 each would be worth the air conditioning guys time (and mine) - given that I'd still have to get him to come in and do the pressure testing and sign the chit.

In the end my guy charged $20 for nearly a metre of extra vertical piping on each machine. Assuming that you pick the units up from the shop, doesn't hurt to put them where they need to go (internal and external units). Easier for him than manouvering them around your house. Not something that he'd bill you for, but something that puts him in a good frame of mind when he's contemplating a reduction on something else. Last thing - since it's nearly always a blistering hot day when you've got him coming in, rig up a bit of shade over the area where he's working outside - if you can without it getting in the way of ladders. For my guy it was an all day job.

digger12
12th May 2006, 12:58 PM
Just my 2c worth..

I bought the unit at cost through my mate who works for Daikin. He also installed it with my help. (only charged for materials for the install. Concrete slabs, copper pipe, ducting etc.)

The whole install was fairly easy, after seeing how it was done. First mount the plate for the indoor unit, put a hole saw through the plasterboard for the pipework and cables then hammer drill out half a brick slightly lower than the inside hole. Next run a new 20A circuit from the meter board above the ceiling down the wall and out the hole in the bricks for the outdoor unit then the interconnecting power and communication cable to the indoor unit. Next mount the indoor unit to the base plate, making sure all 3 pipes pass through the hole in the bricks (liquid small, gas-big, and drain.

Next set the outdoor unit on the slabs and level it. Then connect the pipe work from the units. **Note my mate told me that the R410a gas runs at a higher pressure than R22 and so needs special copper pipe.

Next vac out the system for 20min or so. Do the electrical connections and putting the pipework and cables in ducting whilst waiting for the vac. I didnt know before hand but my unit came pre-charged with enough gas for a certain max length of copper run. So all there was left to do was make sure the system had held vacuume for some time (no leaks) then remove the vac pump and let the gas into the pipework through the service ports.

Next the exiting bit. Turn on the breaker and get the missus to hit the on button on the unit so we can enjoy the sound of an inverter compressor starting up. (quite nice really, if you are into that type of thing....)

All that was left to do was some cleaning up.

Now my point is this. I think the actual install was quite easy. If I did one again I would definately do the same and employ/con a fridgie mate to flare and connect the copper and vac out and charge the system. All my fridgie mates swear by vacuuming out the system first. Also by the time you buy flaring tools and do some practice flares it is probably just as cheap to have someone do them.

Hope that helps someone. Any questions feel free to ask.

thedoctor_74
6th July 2006, 08:29 PM
Hi I am an electrician and refrigeration mechanic....just reading through these posts and sure i can respect that most people want to do things as cheap as possible but by not using licenced tradespeople for this kind of work you are breaking the law. Electrical work on fixed wiring of any kind and refrigerant work require "Licences" and to perform this work without one is an offence.

Remember if you have a fire in your house or an accident of any kind due to any of this work you will "NOT" be insured..... that extra few hundred bucks soon becomes worth it... so for all you guys using a tradesmen good luck, all you who dont think twice about the long term out comes first insurance warrantys etc.

kompsj
10th October 2006, 01:43 PM
I am a licensed fridgy, quite happy to sign of self installs if they are installed properly. This is not illegal. However, conditions, are :-

1) Install is done well, indoor unit/outdoor unit is level and correct clearances to walls, refer to installation manual for these, simple really.
2) Correct copper used for gas type, I am finding many of the cheaper types are coming with the copper pipe supplied. The cheaper units seem to work fine. I have one at home and love it. Simple really.
3) Only I flair the copper, I will bend the copper as this must be done correctly with the correct tools, and you need to make oil traps sometimes and sometimes not, depending on install. Most back to back systems are quite simple.
4) I weld the copper joins if required as you have to use the correct silver content rods depending on the type and run dry nitrogen throught the pipes in order to comply.
5) I vac the unit and check for leaks, as I have the latest tools, including leak detectors, and gauges.
6) I put more gas if needed due to extended runs. Although rare on installs. You pay for the extra gas, fair enough.

Price = $120-$140 depending on location. This buys 1-2 hours of my time. I'm in Preston, Vic,close to Melbourne CBD and do these on weekends or weekday evenings. Call me on 0417 209 552 or email me. Always happy to help a DIY person (me being one). Will do full installs as well and teach you for next time.

Pulse
10th October 2006, 08:02 PM
Kompsj, welcome to the forum and thanks for your offer. Its good to see tradies who are open to the DIY spirit.

Cheers
Pulse