So I just built a 30x54x16 shop and I installed a 36k Mr. Cool DIY minisplit. I live in Boise, Idaho and so far it seems to be heating it ok but my question is about how much it is running. It seems like the condenser is running almost constantly. It does seem to have a low and high mode and most of the time it seems to be in low mode but should it be running this much? I've considered getting a wall mounted electric heater to supplement it but I don't know if it's needed. The temps here are around 25 at night and 43 during the day and like I said, it seems to be able to keep it at 65 but it just runs a lot and I don't want to burn it up prematurely.
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Is my Mr. Cool mini split running too much?
- Thread starter ebridges
- Start date
ipdaley
Active member
The starts and stops is what wears out the compressor. Long run times is GOOD (assuming the system is installed correctly). On the hottest day of the year if your system is cycling, it is oversized. In Idaho I would expect long run times with a heat pump in winter. There are a lot of variables I am leaving out. I’ll close with this analogy:
Ever push a car from a dead stop across a parking lot? It takes a lots of force to get the car rolling. Once the car is moving, it takes much LESS energy to keep it moving. Your heat pump is the same. It takes time and energy for the compressor to start and get the system to a steady state. Once those temps and pressures have stabilized, it takes less electricity to keep it running.
I purchased a two year old Silverado with 140k miles... at a steal! Those miles were from commuting in and out of Houston, TX, 140 miles round trip. Truck was like new. Runs great at 190k today. My brother had a 73 Chevelle in 1992. His wife’s grandmother’s car 20k miles (yes 19 years old). Like new. She drove it to church, twice a week, less than a mile away. Also drove to grocery store about a mile away. Was like new BUT it smoked. Reason: car never got warm and that wore the valve guides.
On HVAC, long run times are GOOD (assuming equipment is working correctly). I DESIGN split systems. short cycling KILLS equipment.
Ever push a car from a dead stop across a parking lot? It takes a lots of force to get the car rolling. Once the car is moving, it takes much LESS energy to keep it moving. Your heat pump is the same. It takes time and energy for the compressor to start and get the system to a steady state. Once those temps and pressures have stabilized, it takes less electricity to keep it running.
I purchased a two year old Silverado with 140k miles... at a steal! Those miles were from commuting in and out of Houston, TX, 140 miles round trip. Truck was like new. Runs great at 190k today. My brother had a 73 Chevelle in 1992. His wife’s grandmother’s car 20k miles (yes 19 years old). Like new. She drove it to church, twice a week, less than a mile away. Also drove to grocery store about a mile away. Was like new BUT it smoked. Reason: car never got warm and that wore the valve guides.
On HVAC, long run times are GOOD (assuming equipment is working correctly). I DESIGN split systems. short cycling KILLS equipment.
fitter30
Well-known member
Minis with a inverter compressor run 24/7 unless thermostat is satisfied by 2-4* then just the condenser shuts down not the wall unit.