Wood fueled furnaces cannot be 100% of load for HES jobs.
You can use 5% electric resistance to make it pass HES.
Also, a 100% pellet stove will pass HES without errors.

HVAC system types: Direct Heaters can now be used as a HVAC option.
However a direct heater must not be electric. An electric heater must be shown as electric resistance.

Conditioned Area: Be sure that the length x width x number of floors adds up to at least the total conditioned space entered in the building data. It would be best to be a couple sqft over than under. This sometimes causes HES errors for the foundation if the numbers are not in sync.

Floors above grade: DOE doesn't support partial floors above grade (1.5 stories). They just round up to the next full number. This can throw the dimensions of the house off because of the foundation. If you have a 2000 sqft home that is 2 stories, the full basement would be 1,000 sqft (the same size as the main floor). A 2000 sqft home that is 1.5 stories would have a 1500 sqft basement. You can compensate DOE and correct the job by manually entering the sqft of the basement (or crawl) in detail page. Now, if you leave the Snugg Pro job as showing a partial floor, DOE will accept the job and adjust on their end.

Foundation walls: The DOE limits of the improved R value of basement and crawl walls to R 19.

HVAC distribution systems: DOE will not accept different heating and cooling percent of loads for a shared duct systems. They indicate they will accept up to a 5% difference in loads, but that usually also gets an error. If you encounter a home that has (for example) 100% heating and 50% cooling on the same shared duct system, then you will need to enter those systems separately.

Multi-family: The only type of multi-family homes that are allowed (at this time) are side-by-side units with shared walls, like duplex, or townhomes. They will not accept units that have shared ceilings or foundations. Also, see Shared Walls below.

Shared walls: A shared wall cannot be the front or the back of a townhome. Shared walls can only be the side walls, as determined by the direction the house faces. It can only be the right, left (or both right & left). So be cautious when indicating the orientation of the home, making sure that it is showing correctly for shared walls. Also, you must specify a shared wall as being 51% or more if you're going to call it a shared wall. The DOE makes it an all or nothing situation. If you're less than 50% shared, you can either call it 51% shared and still call it Single Family Attached, or change the home to Single Family Detached where there will be no shared walls.

Shared walls with windows: at this time DOE will not accept any windows on a shared wall even if it is only partially shared. Example: A 50% shared wall cannot show any windows so you might want to include the glass sqft on a different wall.

Skylights: The DOE limits the size of skylights to 300 sqft.

Solar water heaters: are not accepted by DOE at this time.

Wall height: DOE restrictions for wall height Min 6’, Max 12’.

Wall siding types: DOE will not accept "other" or "stone veneer" as a siding type. They do accept 'brick veneer'.

Propane (LPG) wall furnace (direct heater)

Tankless water heaters, expanded fuels to include Electric, Gas, Propane.

The UEF energy standards for water heaters.

Solar Screens for Windows

Electric boilers (which have to be shown as electric furnace in Snugg)