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Type786 requires the same number of air flow rate steps for both heating and cooling performance data files. I have manufacturer data (Goodman) with 4 flow rate steps for cooling, but for heating the table provides only one flow rate.
What do you recommend?
-
Use only the cooling rating flow rate (1160 CFM) for both modes (single step each)?
-
Copy the single heating flow rate 4 times to match the 4 cooling steps?
Thanks.
Either of your proposed solutions would work. If you do not plan to change the air flow rate during your simulation then your first suggestion makes more sense to me. In the second solution I suspect that there would actually be a performance impact by changing the air flow rate that would not be captured.
One thing you could do is to plot the cooling COP and capacity of the device you're modeling from the data you have as a function of air flow rate. Compare that curve to the same plot of the sample data file that is provided with Type786. If the two curves are largely similar then you could take the shape of the heating COP and capacity curves as a function of air flow rate from the sample heating data that is provided with Type786 and apply that curve to your manufacturer's data.
~david
yalikara Topic starter
20/04/2026 4:39 pm
@davidbradley
Heating mode is out of scope for my project. I am using Type786 as an air conditioner. Although there are other types dedicated to air conditioning only, such as Types 921, 651, and 144, I preferred Type786 because it includes a variable-speed compressor model and also allows the user to specify the supply air delivery temperatures and heat sink temperature.
I copied the heating data for a one-step air flow rate and used them four times as placeholders to avoid an error message. It worked. I would like to share this for other users' knowledge.
Thank you for your response.
DavidBradley 20/04/2026 7:21 pm
@yalikara
yes, that solution is perfectly acceptable for your use case!
~david
