On 7/4/2022 at 9:14 AM, grain said:

I spoke with an AC installer a couple of years ago and he explained that an AC installed in my unit must run cables from the 5th floor down to the ground floor, where the meters and RCAs are. 

That depends largely on the size of the systems. location of the outdoor unit with respect to the fan coil unit and whether or not you require the system to be driven via a tarrif different to your power outlets.

Some installations will have sufficient capacity on the power outlet circuits to handle to extra loading.

Most installs these days are covered by combo circuit breaker elcb by law and maximum demand in final sub circuits is vastly different from a few years ago.

That plus the majority of the RAC systems are screw compressors (quieter) inverter type given the compressor ramps up and down in speed depending on the heat load.

Starting of these is much less demand on the cabling as opposed to the old problem when they were "bang" online run-of-the-mill compressors.

11 hours ago, bluejets said:

That depends largely on the size of the systems. location of the outdoor unit with respect to the fan coil unit and whether or not you require the system to be driven via a tarrif different to your power outlets.

Some installations will have sufficient capacity on the power outlet circuits to handle to extra loading.

Most installs these days are covered by combo circuit breaker elcb by law and maximum demand in final sub circuits is vastly different from a few years ago.

That plus the majority of the RAC systems are screw compressors (quieter) inverter type given the compressor ramps up and down in speed depending on the heat load.

Starting of these is much less demand on the cabling as opposed to the old problem when they were "bang" online run-of-the-mill compressors.

I think you meant to say scroll compressors not screw compressors.

23 hours ago, Hugh Cow said:

I think you meant to say scroll compressors not screw compressors.

No, screw compressor.

Like many things worldwide, some say pot-ar-to, some say pot-ate-o.

 

example to chew on........ https://www.compressorsunlimited.com/blog/carrier-screw-compressors-the-basics

On 7/11/2022 at 8:59 PM, sometimewoodworker said:

You get a gold star ⭐️ ???? 

Thank you, but working in the refrigeration and airconditioning industry as firstly a tech and later as an Engineer for 50 years probably helped.

22 hours ago, Hugh Cow said:

Thank you, but working in the refrigeration and airconditioning industry as firstly a tech and later as an Engineer for 50 years probably helped.

Yes, well same this end so as they say, there ya go.

On 7/13/2022 at 7:53 PM, bluejets said:

No, screw compressor.

Like many things worldwide, some say pot-ar-to, some say pot-ate-o.

 

example to chew on........ https://www.compressorsunlimited.com/blog/carrier-screw-compressors-the-basics

OK. I didnt realise you were talking about a large commercial system. As you'd be aware A/C screws start somewhere around 75 K/W nominal.