We are on building a light wieght well insulated house on the SE coast of Victoria. We chose Daikin reverse cycle air conditioners for heating / cooling as we understand that they are energy efficient. The local Daikin dealer recommended a 10KW system with 4x2.5KW room outlets PLUS a 9.5KW unit for the main living area. We were keen to use the very efficient US7 units but they advised this would involve 4x2.5 kW US7 units PLUS 2x3KW US7 units for the main living area.
- This seems an awful lot of heating / cooling. Do the companies tend to overestimate the heating / cooling requirements? Is there a way for us to estimate this ourselves? The formula given by choice is vague about cold climates.
- The US7 option is more expensive and less convenient with 2 units in the main living area and in all resulting in 6 separate heat pumps. How much more efficient that the recommended 2 larger units are they likely to be? They assure us that we can zone control and heat/cool only required areas at any time.
We will probably use the units mostly for heating, and just occupied rooms at any one time.