Prosecution Insights
Last updated: April 19, 2026
Application No. 18/757,791

Methods for Defrosting a Heat Pump and Heat Pumps Comprising a Defrost System

Non-Final OA §112
Filed
Jun 28, 2024
Examiner
BRADFORD, JONATHAN
Art Unit
3763
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Fenagy A/S
OA Round
1 (Non-Final)
76%
Grant Probability
Favorable
1-2
OA Rounds
2y 9m
To Grant
97%
With Interview

Examiner Intelligence

Grants 76% — above average
76%
Career Allow Rate
880 granted / 1159 resolved
+5.9% vs TC avg
Strong +21% interview lift
Without
With
+21.3%
Interview Lift
resolved cases with interview
Typical timeline
2y 9m
Avg Prosecution
26 currently pending
Career history
1185
Total Applications
across all art units

Statute-Specific Performance

§101
1.2%
-38.8% vs TC avg
§103
48.5%
+8.5% vs TC avg
§102
19.3%
-20.7% vs TC avg
§112
25.3%
-14.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1159 resolved cases

Office Action

§112
DETAILED ACTION Notice of Pre-AIA or AIA Status The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Drawings The drawings are objected to as failing to comply with 37 CFR 1.84(p)(5) because they do not include the reference sign 20” mentioned in the description. Additionally, in Fig. 6 the arrow pointing to the left to box labeled “Defrost process continues” appears to be backwards, and should instead point to the right. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance. Specification Applicant is reminded of the proper language and format for an abstract of the disclosure. The abstract should be in narrative form and generally limited to a single paragraph on a separate sheet within the range of 50 to 150 words in length. The abstract should describe the disclosure sufficiently to assist readers in deciding whether there is a need for consulting the full patent text for details. The language should be clear and concise and should not repeat information given in the title. It should avoid using phrases which can be implied, such as, “The disclosure concerns,” “The disclosure defined by this invention,” “The disclosure describes,” etc. In addition, the form and legal phraseology often used in patent claims, such as “means” and “said,” should be avoided. The abstract of the disclosure is objected to because it includes the implied phrase “Methods are disclosed”. A corrected abstract of the disclosure is required and must be presented on a separate sheet, apart from any other text. See MPEP § 608.01(b). The disclosure is objected to because of the following informalities: line 2 of paragraph [00106] recites “forward line 48 that is connected” but should instead read “forward line 48” that is connected”. Appropriate correction is required. Claim Objections Claim 3, 5, 7, 9, 14, and 15 are objected to because of the following informalities: Claim 3, at line 4, recites “a maximum” but should instead read “the maximum”. Claim 5, at line 4, recites “a maximum” but should instead read “the maximum”. Claim 7 should have line 2 deleted because the step of “determining a maximum allowable pause time” is already recited in claim 1. Claim 9, at line 2, recites “a defrosting medium” but should instead read “the defrosting medium”. Claim 14, at line 5, recites “a maximum” but should instead read “the maximum”. Claim 15, at line 5, recites “a maximum” but should instead read “the maximum”. Appropriate correction is required. Claim Rejections - 35 USC § 112 The following is a quotation of the first paragraph of 35 U.S.C. 112(a): (a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention. The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112: The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention. The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. Claims 1-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Regarding claims 1 and 12, each claim recites “a plurality of outdoor evaporators each comprising a number of fans”. However, this configuration does not appear to be included in the original disclosure. Instead, each evaporator is disclosed as having a single fan 42 (for example see Fig. 1). Regarding claims 2-11 and 13-20, the claims are rejected due to dependence from claims 1 and 12. Claims 1-20 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Regarding claims 1 and 12, the terms “a number” and “several” in each claim are relative terms which render the claim indefinite. The terms are not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. Specifically, one of ordinary skill in the art would not readily recognize what amount of fans and coils would constitute “a number of fans and a number of coils”, or what amount of defrost processes would constitute “several defrost processes”. For examination purposes the claims are presumed to mean that the terms “number” and “several” constitute at least two of something. Regarding claims 2-11 and 13-20, the claims are rejected due to dependence from claims 1 and 12. Further regarding claims 12-20, the claims refer to the “defrost system” performing operational steps. This limitation is indefinite as it is unclear how the claimed system performs the steps. For examination purposes the claims are presumed to mean that the system includes a controller configured to perform the operational steps. Examiner Note Claims 1-20 are considered to read over the prior art of record because the prior art of record does not teach or suggest the claimed combination of features including performing several defrost processes each having a duration separated by a pause without defrosting when an evaporator coil temperature is below a value, wherein a maximum pause time is determined depending on an ambient outdoor temperature. For example, while Lee (US 2012/0266616; see paragraph 47) and Yoshimoto (US 2022/0214091; see paragraph 192) teach performing a plurality of defrosting operations for multiple outdoor heat exchanger coils, there is nothing in the prior art of record that would, reasonably and absent impermissible hindsight, lead one of ordinary skill in the art to modify the operation of the cited references to include determining a pause between several defrost operations based on an ambient temperature in the manner as required by the claims. However, these claims cannot be considered to be "allowable” at this time due to the rejection(s) under 35 U.S.C. 112 set forth in this Office Action. Therefore, upon the claims being rewritten or amended to overcome the rejection(s) under 35 U.S.C. 112 set forth in this Office Action, further consideration of these claims with respect to the prior art will be necessary. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to JONATHAN BRADFORD whose telephone number is (571)270-5199. The examiner can normally be reached Monday-Friday 8:00 - 4:00 ET. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Jerry-Daryl Fletcher can be reached at (571)270-5054. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /JONATHAN BRADFORD/ Primary Examiner, Art Unit 3763
Read full office action

Prosecution Timeline

Jun 28, 2024
Application Filed
Jan 11, 2026
Non-Final Rejection — §112 (current)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

1-2
Expected OA Rounds
76%
Grant Probability
97%
With Interview (+21.3%)
2y 9m
Median Time to Grant
Low
PTA Risk
Based on 1159 resolved cases by this examiner. Grant probability derived from career allow rate.

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