Hmm, slightly new territory for me here; as I said we don't get involved with A/C much over here.
If the EER of the unit is not available, I would guess you would just have to resort to an estimate of a typical value to get a rough idea of the current.
I did a Google search on keywords "air condition efficiency," and came up with several links which seem to agree that around 10 is a reasonably good EER on modern A/C units.
If we plug that into the formula, it becomes (ignoring p.f.):
Amps = (BTU / 10) / voltage
That will simplify down to:
Amps = BTU / 1200 (for a 120V unit), or
Amps = BTU / 2400 (for a 240V unit)
Would any A/C experts agree with these figures?
