calculating energy usage

[native pepper]

Sadly JohnM, 1978 Bedford buses don't come with a/c.

Triptracks, how much lifepo4 do you have. Still thinking of a 5kw, the problem most have is there is no example for us to follow, unless we run across someone with the same rig and setup. Ours will be a split system, not a wall unit and will be situated in the middle of the bus. Cassettes are very expensive compared to split systems I've found, so out of our budget, is yours an inverter a/c or standard.

[BernieQ2]

Re Peter & Sandra's post about the same head but different outside units . Question? can I change my outside unit to a larger one without changing the inside unit...or would there be a problem re the remote not working or does the remote only work on the inside unit if its the same brand or would it work on a different brand ??
Bernie .

[bagmaker]

you could search the A/C unit technical details for the "C.O.P" and pick the highest value. The little units will struggle compared to the big units, the inefficient units will pull too much load for the same output as a decent unit. As long as you have a high COP rating then its as good as you can get. Ultimately the input power will depend on your required level of comfort. Ensure the one you pick is "inverter" technology to limit cycling once the setpoint is reached -important if the unit is overspecced for your size M/H- and keep to big brand names.
Nothing from a large german supermarket (like I have got )

[triptracks]

Sadly JohnM, 1978 Bedford buses don't come with a/c.

Triptracks, how much lifepo4 do you have. Still thinking of a 5kw, the problem most have is there is no example for us to follow, unless we run across someone with the same rig and setup. Ours will be a split system, not a wall unit and will be situated in the middle of the bus. Cassettes are very expensive compared to split systems I've found, so out of our budget, is yours an inverter a/c or standard.

I have an inverter split with a ceiling cassette - Daikin.
I did I write-up here:
http://caravanersforum.com/viewtopic.php?f=73&t=62832

The ceiling cassette is a very neat solution that uses no wall space. Yes, they are a little more expensive than a wall mount.
The outside unit is larger than the 3.5kW, so you need to allow for this. The ceiling cassette sizes are the same.

[jon_d]

Pepper,

Some photo's of my split in a 72 Bedford.

$600 for the split
$150 for the A/C tech to check it over and gas.
$50 for copper and my time to get it ready



jd

[native pepper]

Thanks Jon, what length is your bus and a/c capacity. The one I'm thinking of buying comes with copper pipe and is fully charged they say.

[jon_d]

9 meters, the AC is about 2.5/2.6 kw.

Even though it's fully charged, the copper pipe needs to be flushed with nitrogen. pressure tested and then vacuumed down. Then the charge is released into the piping.

[native pepper]

Thanks Jon, believe the copper is already primed for the install, connected one end and sealed the other. Will take it to an a/c bloke I know for him to check it out before firing it up. Siting the internal section will be my biggest challenge, not sure where it will go until I see it's physical size. Will have to redesign one of the engine bay lift up doors to provide good air movement and protection from road junk thrown up for the main unit, that will be the easy part.

The rain is back down here, being coming down all night so looks like won't get much done today until it stops.

[jon_d]

ok, it must have taps on the head and the outdoor unit to hold the charge/vacuum and then the air in the copper pipe is just merged.

Mine had plastic dust caps over the head. I made the copper pipes and joined everything up. Then copper and head were vacated after being connected to the outdoor unit.

When he was happy that there was no leak (under nitrogen pressure and then vacuum), he released the charge from the outdoor unit into the head.

The better the vacuum before releasing the charge, the better efficiency

[BruceS]

I read somewhere that most of the pre-charged ones actually have a little extra gas in them that allows the initial install plus one relocation without more gas. I just assumed no vacuum needed but I don't know about that.
If Jamglor is around he might know more?? Jamie?