Correction on my previous comments...
Okay, with all that was written, I felt the need to clarify what was said before by having a direct conversation with the test lab people at the manufacturer. They work on various industry committees, including the one involving the new NSPS. So here it is:
1) The PSG Caddy is certified to EPA Wood stove standard ie below 7.5 gr/hr. This is listed on the EPA web site page 12.
http://www.epa.gov/compliance/resour...tifiedwood.pdf
2) Since the Tundra and Heatmax use the same firebox (with a different aesthetic), the manufacturer filed for EPA certification on those two models and submitted the paperwork. They are awaiting certification (i.e. addition of those two models on their existing Caddy certificate). In the meantime, they have agreed to remove claims regarding EPA certification. Such claims can only be made when the actual EPA updated certificate has been re-issued. The manufacturer expects the new certificate to be re-issued soon.
3)
EPA certification applies to wood heaters. However, it does not restrict the type of wood heater to which the standard is applied. EPA Method 28 is an 'emissions' standard that was created initially for freestanding wood stoves. Nevertheless, nothing prevents a manufacturer to test a wood furnace to the wood heater standard and obtain EPA certification. The same goes for fireplaces. There are many EPA-certified wood fireplaces on the market (BIS, RSF, etc.). In other words, one needs to see EPA-certified fireplaces as wood heaters “designed” as a fireplace.
4) EPA’s decision to remove exemption on furnaces in the upcoming NSPS was in part influenced by the fact that some manufacturers were already able to make clean-burning, EPA-certified wood furnaces. Some EPA representatives have visited the PSG booth during the HPBA Show at more than one occasion to take a closer look at the technology and they have praised the initiative by some manufacturers to clean their combustion even though they were not obligated to do so.
So if I can sum up:
1) There are currently no EPA emissions standard specific to central systems. However, manufacturers can chose to have their central systems (furnaces, boilers) certified to the "wood heater standard" which requires emissions below 7.5 gr/hr. Same logic applies to wood fireplaces.
2) In the new NSPS, EPA is likely to introduce an emissions standard similar to CSA B415.1-10 which will be around 0.40 gr/MJ of heat output. This is subject to review, but it is consistent with the comments Gil Wood made at a presentation to the industry at the 2013 HPBA Show in Orlando.