We rent a unit in a commercial plaza since 2005. We have 2 small saunas that draw about 20-25 amps, frig, freezer, washer, dryer and 2 computers. We have a 100amp service. In 2007, heat/air unit broke down and landlord installed a 480 volt roof top unit and attached a very noisy transformer ( in our unit)and attached to our panel as it needed to be modified for canadian codes. We immediately noticed an increase in electricity costs, but he had sold building. We advised new owners to removed transformer from our unit as it was soooo noisy and also talked about unit on roof and our concerns. Finally when it was time to re-sign lease... transformer moved out of unit but remained on panel. Last month, one of the fuses blew and we were advised that they is a lot of wear and tear on the panel due to the load being above 100 amps. @ electricians have advised that we are personally drawing approx. 45 amps. How many amps would this roof top unit and how many amps for the transformer. We have been forced by our landlord to upgrade to a 200amp service as it is now a fire risk and low and behold he has building for sale again... Electricians have both said roof top unit is old model and not energy efficient and looks tired too and when it dies, a newer unit will most likely be used and we will again be way below our 80% usage as new models only draw about 20 amps... is this also correct? Looking for information that might help us to defend our position. Thank you in advance.

Without knowing any details of the roof top unit, either exisitng or the proposed new, we have no idea how many amps it draws.

Transformers draw a small amount, but negligible, of current.

I think you need to consult with an attorney.