Competition Advocates, LLC 

February 21, 2012 

Response to EPA Questions Dated February 7, 2012 Relating to Pending R32 SNAP Petition 

TO: Dave Godwin, EPA Alternatives & Emission Reductions Branch 

CC: Melissa Fiffer, Margaret Sheppard 

Thank you for your additional questions regarding Daikin’s pending R-32 SNAP application. I have consulted 

with the engineers at Daikin U.S. Corporation and with Daikin Industries Ltd.’s Chief Engineer Mr. Tsujii in 

Osaka, and based on the information I received from them Daikin is providing the following answers to your 

questions below (I have extracted the questions from your February 7, 2012 email and edited them for clarity, 

with questions in blue font and answers in red font). 

Question 1: How were these maximum charge sizes in the chart under item 3 in Daikin’s December 6, 2011 

submittal determined? For instance, do they assume a large number of indoor units or very long refrigerant 

lines from the outdoor unit to the indoor unit(s)? 

Answer 1: These maximum charge sizes were calculated based on the assumption that the R-410a and R-32 

systems are using the longest factory-recommended refrigerant pipe run for these systems from the outdoor 

unit to the indoor unit, a distance of 165 feet. This may account for the larger refrigerant charge than you 

expected. We used the maximum feasible pipe run in our calculation because this analysis is being done for a 

risk assessment, and we assumed the largest possible volume of refrigerant in the system for that purpose to 

simulate the worst-case scenario. In contrast, the Trane presenter who you mentioned at the recent UL 

working group meeting was probably using the shortest feasible pipe run and the smallest possible volume of 

refrigerant in the system that he was describing. 

Question 2: If so, how often would one likely see these maximum values? 

Answer 2: Based on the sales experience of Daikin AC (Americas), Inc., our U.S. equipment sales subsidiary, 

the typical length of the pipe run between the indoor and outdoor unit is approximately 50 ft. Longer pipe runs 

than 50 feet are unusual. 

Question 3: What would be a "typical" charge size for these units? 

Answer 3: The charge of a SEER 18 2-ton R-32 ducted split system with a 50-foot pipe run between the 

indoor and outdoor units would be 10.0 lbs. of R-32. The comparable amount of refrigerant for a SEER 18 R410a 2-ton ducted split system with a 50-foot pipe run between the indoor and outdoor units would be 11.8 lbs.

Question 4: Does the calculation of 425 square feet per pound / 850 square feet per ton sound 

reasonable to you for Daikin equipment? 

Answer 4: Regardless of manufacturers or systems, the floor area (space) per ton should be same. Daikin 

AC (Americas), Inc.’s experience in the U.S. market indicates that the average square fee per ton amount 

ranges between 400 and 500 square feet.

Question 5: Does your table assume a particular type of space or load? 

Answer 5: Our table assumes that the systems are operating in residential-type space in Japan.

Question 6: Also, does your current submission anticipate R-32 equipment being used in 

restaurant or kitchen applications? 

3188 Key Boulevard, Arlington, Virginia 22201, 202-669-2002, mstanga@verizon.net 
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Answer 6: Yes, our current SNAP submission anticipates that R-32 equipment would be used in restaurant or 

kitchen applications as well as in residential applications.

Question 7: Regarding your response 2.b. in Daikin’s January 25, 2012 submittal, did you mean the reverse? 

For example, in the summertime, wouldn't the high-temperature part be the unit in the outdoor ambient, rather 

than the unit inside the cooled space? 

Answer 8: We apologize that the previous answer was incorrect. As you speculated, we inadvertently 

reversed the parts of our previous response 2.b. in our January 25 submittal. The high-temperature part of the 

system will be the outdoor units in the summertime, and the indoor units in the wintertime.

Thanks again, let me know if you have any more questions. 

Sincerely,

Mark Stanga 

For Daikin U.S. Corporation