danski0224
Well-known member
Interesting analysis from duty cycle perspective.
23.45/23.60/23.86 MBtuh at 700/780/900 CFM respectively. (yours may be a little different).
Your 700 CFM spec in first post results in a spec sheet capacity of 23,450 heating btu's at 47º F outdoors and 70º F indoors.
Note that capacity goes down as airflow is reduced. Airflow reduction can be from a restrictive air filter or ****** ductwork or both.
Same pieces of equipment, 27º F outdoors, 70º F indoors, 700 cfm, minus defrost time capacity (Net Integrated) = 15.39 MBtuh.
OP could do an AHRI certificate search for the specific installed equipment, which will give actual installed capacities. Do note that this can be quite the pain in the *** to do.
Rule of thumb heating load, for my location, with "average" construction is 24,000 btu for OP square footage. Not that I recommend this without knowing what "average" means... or without an actual load calc to back up an assumption.
Circling back to the "Did anyone do a load calculation?" question. That no one in this forum likes... except me.
I do not have an internet observer explanation for the claimed temperature rise as the equipment "on" time lengthens. Could be warming up the ductwork. Could be reduction of airflow at the condensing unit if the coil is freezing, which can be normal... or maybe there's electric heat strips.
Basic single stage, non-inverter R410 heat pump capacity direct from manufacturer table, 47º F outdoors, 70º F indoors:
23.45/23.60/23.86 MBtuh at 700/780/900 CFM respectively. (yours may be a little different).
Your 700 CFM spec in first post results in a spec sheet capacity of 23,450 heating btu's at 47º F outdoors and 70º F indoors.
Note that capacity goes down as airflow is reduced. Airflow reduction can be from a restrictive air filter or ****** ductwork or both.
Same pieces of equipment, 27º F outdoors, 70º F indoors, 700 cfm, minus defrost time capacity (Net Integrated) = 15.39 MBtuh.
OP could do an AHRI certificate search for the specific installed equipment, which will give actual installed capacities. Do note that this can be quite the pain in the *** to do.
Rule of thumb heating load, for my location, with "average" construction is 24,000 btu for OP square footage. Not that I recommend this without knowing what "average" means... or without an actual load calc to back up an assumption.
Circling back to the "Did anyone do a load calculation?" question. That no one in this forum likes... except me.
I do not have an internet observer explanation for the claimed temperature rise as the equipment "on" time lengthens. Could be warming up the ductwork. Could be reduction of airflow at the condensing unit if the coil is freezing, which can be normal... or maybe there's electric heat strips.
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