How Much for a Single Phase 40 amp Isolator for Air Con

Just about to start building. Plans and bank approval are all done. Just making the final decision on AirCon. Were originally looking at a 3 phase system. Builder was going to charge $615 for the 3 phase connection to the house and another $590 to run a 3 phase 32 amp isolator for the air con system.

Have just about decided on a single phase system. Approached the builder. They are saying an additional $110 for a single phase 40 amp isolator for the air con (so $700 in total - $590 + $110). Given their standard price for an extra standard power circuit & safety switch is $258, can a 40 amp power circuit for the aircon really cost $700...???

We get 32amp circuits put in for the majority of our ducted systems at a cost of $290+GST

You will also need to check on your single phase supply. Have been told you only get a 40 amp supply on a single phase circuit which is very low if you intend on running a large a/c and lights etc. not sure if this is correct. I had 3 phase installed during our build at a cost of $180 get a breakdown on the extra costs should only be extra for upgraded cable and larger conduit as there is normally no extra charge from electricity retailer for meter and connection

New builds should get at least 100amps single phase now...

Finally convinced them they had made a mistake. They were adding the extra for the 40 amp circuit to the 3 phase price, rather than the singe phase price. So the cost of the 40 amp single phase isolator is now $430.

Still sounds expensive for a single c/b and single phase run of tps cable . ask for a breakdown of cost a c/b cant be worth more than $30 and even a long run 20 meters of 6mmTPS wouldnt bring costs anywhere near this amount.

Well it may seem expensive, but it seems to come with the territory of building a house. You sometimes just have to pay that little extra to have it done by the builder. And they know it.

For what it is worth, this is the approx price list for aircon isolators with the builder:

1 Phase 20amp $280.00
1 Phase 32amp $330.00
3 Phase 20amp $380.00
3 Phase 32amp $580.00

So $430 for the 40 amp single phase seems to more or less fit.

The aircon people would have done the 40 amp single for around $320, but the builder won't let anyone else touch the wiring. And to do it after handover in a 2 story house is way too much trouble.

Talk to your electrician rather than the builder. 20amp isolator for air con (wiring from unit to switchboard as well) cost me $100 cash (with invoice though) at build time. Got him to come back when house was completed to do the same in another room for $180.