7.5Kw Single Phase Aircon Unit , Have I Calculated Correctly ?

[Bacon]

We install a lot of of aircon units and i've never had to put a bigger cable than 2.5mm,As has been said above it's the heating and cooling that is usually assoicated with the KW.

Take today for instance install a 35KW warm air heater thats the output.Supply 2.5mm via 5amp spur with an internal 3.15 fuse. 

 

[kme]

WSoppitt, do you have the manufacturers name and model number for the A. C. unit at all? I could be wrong here ( I haven't seen the spec of the unit, hence why I have asked) but could a type D breaker be needed due to the initial in rush current of the A. C. units?

I could, and probably am, well wrong with My thoughts. :innocent

Andy Guinness

Zee:

Most of the units now are inverter drive; so there isn`t a huge inrush, the way they used to be when the fans kicked in.

If its very, very quiet, when I turn mine on in a morning - two minutes after it comes on, the fan starts winding up - sounds like a turbine slowly spinning up, but faintly, if you know what I mean? "D" curves aren`t required for the newer, incredibly efficient units.

 

[Zeespark]

I apologise for the inaccuracy KME, I only have very limited knowledge of A. C. units, which shows, I will keep schtoom on this subject from now on.

Andy Guinness

 

[steptoe]

I fitted a couple of aircon last year, running off 25A type C's 

 

[batty]

The air source jobbies I did a couple of years back manufacturer recommended they were on 40 amp type D's which as it was domestic the loop on the 10mm cable only just was low enough to pass.

 

[kme]

Zee - see, the above comments show you weren`t wrong to make the suggestion

You don`t have to "keep schtum" - we`re all riding the learning curve rollercoaster everyday

Monday, I was at the Justice Dept - had to replace a 20A TP C curve with a 32A C, `cos the original installer didn`t follow manufacturers spec- so Zs the cable to ensure disconnection, verify c.c.c., and swap breaker. 4 hrs work ( 3 hrs travelling!)

 

[SPECIAL LOCATION]

I apologise for the inaccuracy KME, I only have very limited knowledge of A. C. units, which shows, I will keep schtoom on this subject from now on.

Andy Guinness

Keep your scrotum where?????????????????????????

:|