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Parameter for rough computation of instantaneous heat transfer -- M:1.092
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One version of heat transfer is calculated as M * (TS - TR) * FCFM ) -- the difference between supply and return temperatures multiplied by the airflow multiplied by the constant M.
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The constant M combines factors for the density and specific heat of moist air and scales to an hourly rate for each minute (must divide by 60 after averaging rates)
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Alternatively, we can use ASHRAE Moist air property functions for more complex computation that turns out to yield the same result.
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See this post for explanation.
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Period start11/7/2023 0:00:00
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Period end3/14/2024 23:59:00
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Upstairs input assumptions
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 Baseline flow estimate for upstairs unit (CFM)575
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 Fan watts at baseline102
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Upstairs Results
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 Total minutes in time range185700
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 Minutes compressor active (see note 2) -- include these minutes in COP if have temps323210
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 % of time active17%
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 Average hours per 24 hours4.2
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 System active power use -- compressor (kwh)964
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 System active power use -- fan (kwh)51
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 Compressor standby power use (kwh)106
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 Fan standby power use108.2
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 Total minutes for which have both supply and return temperature122968
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 Active minutes for which have both supply and return temperature21933
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 Max temp split47.4
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 Average temp split while active24.0
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 Total BTU produced (active and have temp), using M factor above5407739.7
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 Total BTU heat converted to KWH1584.9
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 Corr. system power -- only while temp avail all compressor plus fan while active658.4
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 COP over season reported (including compressor standby but not fan standby)2.4
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 COP over season reported (excluding all standby)2.69
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Memo: ASHRAE Properties Library computed average values
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 Return Air W (moisture content)0.0000
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 Supply Air W (moisture content)0.0000
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 Return Air Density0.0000
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 Return Air Specific Heat0.0000
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Memo: Total heat produced estimate
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 Total compressor kwh while active964
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 Total therms heat produced 88
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 Check val: Number of zero value compressor minutes12698
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Compressor heating threshold60
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Fan on threshold2
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Conversions
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BTU to kwh -- 1/34120.0002930832356
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So, pound force per newton4.448221909
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Inches2 per meter 21550.0031
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PSI/millibar0.01450377281
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Notes on time consistency:
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The power sheets use time from Emporia downloads which shows EDST until November 5 at 2AM, then falls back (line 24963) and repeats.
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 The power sheets return to EDST on March 10 at 2AM, dropping the 2AM hour (line 206462).
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 Total time period, Nov 7, 00:00 EST to March 14, 23:59 EDST. Predicted row checks:185701129Days
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 For the TRH logging:
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 Govee is all EST
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 Hobo download from gateway is all EDST
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 Hobo data loggers transition back to EDST skipping an hour like Emporia
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Shifted from Gateway use to direct download from loggers on December 25 (see log line # on TRH sheets)
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 Missing Temp data is BLANK -- after interpolation, only gap is supply temp upstairs from 12/31 to 2/13
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 Logan data is GMT with appropriate shifts for matching to Emporia rows, Row count checks.3098
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 (Note that have extra row to match values that round to the missing EST to EDST hour.)
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