DIY self install Aircon?

[tony sayer]

Anyone ever done one of these at all, the wall mount split system ones?

Be interested to know of what experiences anyone has had.

Cheers...

[T i m]

Well, it was pretty straightforward really (but that may depend on the make and model etc).

As it happened I had a hole though the outside wall that was there for a wall mounted gas heater flue and the hoses came with isolation valves and quick connects that made splitting the hoses easy.

I mounted the external unit on the outside wall (I think I 'hangs' from two screws first then held down with one or two more), poked the two gas hoses, one condensate drain hose and one cable (to power the fan, from memory) back though the hole and hooked them up to the floor standing unit inside.

As an aside ... a mate had one of the low level wall mounted units fitted and has since remove and re-fitted it himself but it wasn't a split unit but one with a through wall hose.

Yesterday I *fixed* [1] the small exhaust hose though wall unit he picked up a couple of years ago for his shop by cleaning the main filter and stripping the panels and cleaning the dust from the hot side rad (that didn't have a filter for some reason).

Cheers, T i m

[1] It also involved 3D printing an adaptor plate to convert the large hole on the output to the smaller hose he had though the wall to minimise the leakage of hot air back into the system and causing it to shut the compressor down. He has a bigger unit on it's way tomorrow so I can see my core drill being required again. ;-)

[Capitol]

I've fitted 3. All 1200BTHU. I first mount the outside unit on a wooden platform from 50mm thick timbers about 1 to 2.5 ft above the ground. The unit is heavy! The robust wall brackets come from Toolstation or Wickes. As the unit needs to pull air through the fan I space the units 75mm+ from the wall for ventilation. The exact position is determined by local obstructions. Remove the indoor unit housing at this tage. I very carefully work out the indoor unit location and mark it up, I drill a 60mm approx hole in 3 stages(6mm pilot through the wall from inside and then 60mm core drill from each side of the cavity to reduce spalling at breakthrough) where I want the indoor copper pipework to come through the wall, position the indoor unit mounting frame where I need it to be to allow the pipes on the indoor to pass through the wall after being carefully bent to be at right angles to the indoor unit. The pipes will pass easily through a cavity wall IME, allowing the copper connections to be made outside. The large hole will also allow the electrical cable to pass through to the outside unit. Having given the indoor unit a first trial fit, I then determine where the condensate tube pass through hole needs to be at the other end of the unit and drill a 20mm approx hole for this. At this stage, I mount the indoor unit with all the wires and condensate tube attached and passed through the wall. You may have to take more of the housing off the indoor unit to connect the wires. The coupling copper pipework supplied coiled IME is a pain to unbend, rebend without kinking. Care is required and it is usually too long. As the coupling flares are critical to getting a fully gas tight seal I've never cut the pipework back. Aircon pipe work is brazed, not soldered IME. The next stage is to determine how the bent pipework is going to run and where the spare pipework is going to be lost! Think long and hard before this stage as mistakes are painful! Then very carefully bend/unbend and connect the pipework, temporarily, fixing the external unit end first as it gives a rigid mounting. Keep bends as shallow as possible. The foam insulation on the copper pipework is not bird claw proof so it needs covering either with the tape supplied or a quick and dirty wooden preservative coated piece of fabricated trunking. Before the covering stage, loosen the pipe connections and apply minimal quantities of refrigerant sealing compound to the connections before tightening the pipework up. At this stage offer up a couple of prayers and release the gas stored in the outside unit into the indoor unit. Do not run off too much gas or cooling/heating will not be effective. Switch on the unit and you should be in business. Fix the electrical cables as desired. Decide where you want the condensate tube to run and fix it, cutting it back as required. Give it a day or 2 then fix the trunking if required. Mine are all still running OK, the oldest in the garage is 8 years. I mainly use them for heating. Probably missed out a bit of experience as I did the last one about 3 years ago and the memory is failing a bit these days! As they will probably need regassing after 10 years make sure that the engineer can easily access the gas connections with his regas pipe connections. He might be a large individual so access space is advisable!

[dennis]

Yes. I fitted one from vyair but they don't appear to do them anymore.

It was one where the compressor is out side and the inside unit is a fan and a big radiator.

Easy to do..

put wall plate on wall, core drill for the hoses poke hoses through and multi-core lead for the compressor (the controls are in the internal unit) connect the quick connect connectors and the power plug to the outside unit connect the inside unit to a 20A feed (that's what it said even though draws less than 2kW) Turn it on.

Gives ~5k of cooling or heat.

[Graham Nye]

Most of that ~2 kW is motor => big start-up surge.

A modern unit might have an electronic motor controller (VFD) which can reduce the surge.