inverter air con

[Busman]

Thats pretty close Martin, when we first start one of the aircons we pull about 60 amps for a couple of mins, then very quickly down to 40 amps, then as soon as set temperature gets close, around 20, dips lower if fan speed slow.
Thats on a 24 v system of course, the 240 volt draw is 6, 4 and 2 respectively (divide by 10)

We routinely see 100+ amps at 24 volts coming in, just for fun once I dropped the 24 v bank to 24 volts and then enabled the 3 solar regs and the 2 chargers (1 in each inverter charger at 70 amps each) So, around 240 amps pouring in but then I went and felt the 70mm square battery cables and they were getting way too warm, so stopped that little experiment quickly. Liths were fine though no heating there.

[Barboots]

I was just out in the van running our late model (and reasonably quiet BTW) Cormorant on heat for free. Ignoring the fan-only start routine, it commenced heating at 95A. Once well underway and getting quite hot it had come up to just under 115A maximum (at ~13V indicated). Supply was a 400Ah lithium pack of T1 goodness via a cheapo BitDeals 2016 model W7.

I realise this thread is about inverter systems, but thought some comparative data might be of interest.

Cheers,
Steve

[Riverlander]

Hi. I am fitting a domestic air con. on the back bar on our caravan. Should it be mounted solid on the bar or on rubber mounts. Was going to put it on rubber blocks but wondered if that may cause problems as it would tend to move more than the van.
Cheers John

[jon_d]

Rubber.

Otherwise the vibrations of the compressor/fan may be felt in the van when running.

[T1 Terry]

Hi. I am fitting a domestic air con. on the back bar on our caravan. Should it be mounted solid on the bar or on rubber mounts. Was going to put it on rubber blocks but wondered if that may cause problems as it would tend to move more than the van.
Cheers John

The type of pipework needs to be considered as well, constant working (bending movement) of copper pipes results in work hardening followed by fracturing, so the movement of the unit on rubber mounts could cause problems later on. I mounted our unit on rubber but used flexible hoses rather than the rigid copper tubing. This has its own problems, the hoses leak over an extended period resulting in regassing more frequently than solid copper piping systems. I'm planning to switch to butane as the refrigerant so the regassing costs are trivial and the energy efficiency of the whole system improves by better than 20% apparently along with quieter running as the head pressures are lower. Can't confirm or deny these improvements cause it's still on the "to do one day" list

[native pepper]

I'm in the process of putting a split inverter A/C on the bus and was wondering about flexing popes from vibration, yet to decide on what type of piping to use. Actually haven't got a clue what types of pipe there are and was going to ask the advice of the bloke who I'd get to connect and charge the system.

Is there a specific type of butane to use Terry, have heard from others that it's cheaper and easier to use that refrigerant, don't have a clue about it.

[BernieQ2]

My split system has the pump unit bolted directly to the floor . The head is about 4 feet above , only copper pipe . No problem with using it over the last 3 years .
About a year ago I had the opportunity of buying a lpg gassing unit kicking myself since...I should have bought it.
Bernie

[T1 Terry]

I'm in the process of putting a split inverter A/C on the bus and was wondering about flexing popes from vibration, yet to decide on what type of piping to use. Actually haven't got a clue what types of pipe there are and was going to ask the advice of the bloke who I'd get to connect and charge the system.

Is there a specific type of butane to use Terry, have heard from others that it's cheaper and easier to use that refrigerant, don't have a clue about it.

Isobutane is the most suitable although I plan to experiment using the butane in the gas stove cans, but don't take this as a recommendation or a qualifier that it is suitable for the job.
The use of HC gases in the refrigeration industry has the same absurd reactions as lithium batteries for house battery use, a few understand and embrace the move while the majority follow the "it will explode and kill everyone" spread by those who will loose their grip and $$ extortion if there is a move away from HFC gasses.
There is a company Hi Chill that blend gasses for different refrigeration purposes and I am lead to believe they include a flame retardant to settle the nerves of the doubters. Bob (BobnBev) has far more experience with this stuff and uses it in the RV fridges he repairs as a hobby.

T1 Terry

[native pepper]

Sounds like a job for someone who knows and that's not me. Thanks Terry will see what happens when ready to get it done and what the bloke says about using lpg.

[bagmaker]

the copper TUBING (pipe is measured on the inside diameter, tubing on the outside) is readily available for refridgeration stuff pre-covered in an soft foam insulation which gives excellent support and vibration insulation as well as thermal insulation. Simply use large enough supports/clamps/ cable ties to go around the outside of the insulation instead of the tube.
Check with your A/C system supplier for the tubing supply as well, they generally have the right diameters for the system you are purchasing. Figure where the big bits will be mounted first though, so you know how much tubing to get.
Once completed (its not hard, purchase some tubing cutters and benders for the job, you will still be way in front of paying for a bloke to do it, some youtube time prior will help) get a fridgy to vac it down and gas it.