Aircon pipes spanner size

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I think an important point here is experience and feel, if you have these then there is a good chance you will get the torque in the right ball park, get a 20 stone gorilla of a fitter tightening down a 4BA brass nut and bolt then be ready to replace it as it has stripped, on the the other get some gamer who has never been out of his bedroom tightening down the 32mm nuts on the back actor of a JCB then there is a fair chance it will not be tight enough.
 
I think an important point here is experience and feel, if you have these then there is a good chance you will get the torque in the right ball park, get a 20 stone gorilla of a fitter tightening down a 4BA brass nut and bolt then be ready to replace it as it has stripped, on the the other get some gamer who has never been out of his bedroom tightening down the 32mm nuts on the back actor of a JCB then there is a fair chance it will not be tight enough.
Totally agree.
 
Coincidently a recent MOT suggested I should change the front brake pads on my car.
Tried to loosen the wheel nuts with the 12" long wrench in the toolkit.
No go, even jumping on it.
In the end it required a socket and a 3 foot extension, and jumping on it .
Went around all four wheels and loosened them and retightened with the tool.
The wheel nuts had been "torqued" by the "professionals" at the tyre depot.
What hope would I have had of changing a flat on the road ?
 
I’m sure all of what you say is theoretically true, in practice however not really needed. I’ve just had £28,000 of AC installed in my commercial premises and all of the joints were tightened by the Armstrong method and an adjustable spanner. This was installed by an AC engineer who I have used over the last 30 years, not once has a pipe joint ever leaked or failed. My home installation consists of some 13 split Mitsubishi Heavy Industry units, again I only used an adjustable spanner and arm power.
The same style of connection is used on car brake lines where pressures of 10,000 psi and above are easily achieved, I don’t feel refrigerant gasses getting to the dizzy heights of 400 psi max are really going to test the materials or joint integrity to any great degree.
Only my viewpoint, I am an engineer but not an AC engineer and call on practical experience rather than a university theory book.
Car brake lines use a 'bubble flare' on steel lines which is different to a HVAC 45° flare with an acme threaded brass nut on soft drawn copper lines. Occasionally you'll see 'double flares' used in HVAC as well. As far as torque settings go it's the same debate as it is in the electrical industry... is it necessary to use a torque calibrated tool or is experience and feel sufficient.

The manufacturers go to great lengths to test the ideal torque and if you follow their recommendations you're covered if a correctly made flare or wire termination fails. I generally make a point of using torque tools just because it's almost no extra work and if there is a leak or burned termination I know there was nothing extra I could have done to prevent it.
 
Hey! I had the same issue when I was setting up my DIY split aircon. For the 1/4" and 3/8" fittings, you’ll need a 5/16" spanner for the 1/4" one, and a 7/16" spanner for the 3/8" one. I ended up getting a basic spanner set from the local hardware store, and that worked perfectly.
 
Thanks Dricah.
But earlier posts suggest that the brass fittings may be 1/4" and 3/8" inside, but the compression nuts may be various sizes depending on the manufacturer.
I'll wait until the aircon arrives.
Re torquing.
So in what situations do you agree that torquing is necessary ?
Do you tighten up your big-end bearings and cylinder head by "feel" ?
 
What hope would I have had of changing a flat on the road ?
Doesn't sound very high for you, but If it was me, I'd have every confidence I'd have got the wheel off. Brute force. Use the jack under the wheel brace. You can even place the brace and drive in the correct direction to loosen, using the road.
So in what situations do you agree that torquing is necessary ?
Do you tighten up your big-end bearings and cylinder head by "feel" ?

Critical components, so realistically all I use a torque wrench for would be engine components or road wheels. Even trust the electric impact on driveshafts, brakes etc. No way would I consider in this case, I even own crows foot wrenches (metric) and a selection of torque wrenches.......

I like the Knipex plier-wrench and would probably reach for them in your case. A pair of decent quality adjustable spanners would also be fine. If you have spanners that fit - lovely. I have a set of imperial flare nut spanners and might look to see if they go small enough.

Not done any AC like this, but done lots of car brakes and tighten until resistance significantly builds then stop - don't give it everything you have. That said your wheel nut anecdote makes me think you may be less likely to over-tighten than some ;)
 
"Use the jack under the wheel brace. "
Great idea, wish I'd been able to try that on the overtight bolts.
My 500ft/lbs fix versus the corner weight of the car on the 1ft brace.
Not sure I need to get imperial spanners, a decent adjustable wrench would do.
That's what I use on 15mm and 22mm compression fittings for water pipes.
I wonder what the torque sped is for those :)
 
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wonder what the torque sped is for those
My rule of thumb is , for most things, finger tight then nip it up. If it’s carrying any great load ( mechanical or electrical ) then it gets a grunt as well. If really critical I have torque wrenches including a 1000V VDE one, torque drivers 1/4” and 3/8” from my days of servicing diving equipment, and a Wera and Wiha torque driver. Probably got too many….oh, and a torque calibration tester as well
 
Hi all

I'm getting the tools together to install an ElectriQ 12000BTU DIY Split Aircon, delivery in 5 weeks time.

What size spanners do I need for the 1/4" and 3/8" flanged copper "compression" fittings ?

A simple enough question for google, but zero correct results, just loads of results for 15mm and 22mm fittings :-(
Where do you live as I do not know of any DIY install aircon in the UK due F-Gas regulations?
 

for sale doesn't mean they are DIY install (even though they often advertise it as that). same as many shop sell electrical stuff, doesn't mean they are designed for DIY installation

i think there are some that are designed that you don't need f-gas. the pipes have a plug/socket type connector (also means you can't shorten the pipe). almost all do state in the manual that you need fgas to install, even the 'DIY' ones
 
for sale doesn't mean they are DIY install (even though they often advertise it as that). same as many shop sell electrical stuff, doesn't mean they are designed for DIY installation

i think there are some that are designed that you don't need f-gas. the pipes have a plug/socket type connector (also means you can't shorten the pipe). almost all do state in the manual that you need fgas to install, even the 'DIY' ones
I'm told there are a few around using propane as a refrigerant and you don't need F-Gas for that?
 
yep, probably sould have googled that earlier... for some reason i thought mine was r290 and i know its not propane... quick look and mines r410a....
Im sure some of my newer ones are 410a too. I definitely have a bottle/cask of it ;)
 
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