I'm posting my question here because I have no idea where else to post it.

We're looking at the IECC 2012 requirements for mechanical equipment and have stumbled upon something interesting. In achieving the High Performance HVAC requirement, a 90% AFUE burner is required. This isn't a problem for residential, but I didn't think this type of high efficiency burner was available in a packaged rooftop unit.

My question is, are there any packaged rooftop units out there that do reach the 90% rating?

This seems strange to me, and looking at some big names (York, Trane, Carrier) don't have literature for a 90% efficient heater.

I have been thru the Federal funded Training class and I do not see where the 90% is coming from. Table 6.8.1.E of the ANSI/ASHRAE/IES standard 90.1-2010 (IECC-2012) requires 78% to 81% depending on the equipment.

DrRTU
Table C406.2(4) is where you will find the 90% for heating. This is in IECC 2012. The standard table 403.2.3(4) of IECC 2012 shows the efficiency of 80%, which is what you would expect.

This is a glaring point when you are working with COMCheck. Very easy to see what is required when the Advanced HVAC option is selected.

I cited a non section 406.1 upgrade. This is the big fault I find with ICEE 2012 in a design build concept. We have been quoting new work with C406.1.2 as mandatory for the electrical system. My State is Illinois and we have not implemented it as yet. Permits at of 1/1/13 will be required to adhere to IECC 2012