Overcharged minisplit condenser leads to higher electricity bills
I believe I have solved my problem of why my ductless minisplit system was performing so poorly. My condenser was overcharged with refrigerant by 3 lbs. I have attached a chart of my energy usage for the past few days. On the date of June 25th, the HVAC contractor came out and removed 3 lbs. of refrigerant from the system and thereafter, you can see that my energy usage dropped by 40-45%.
On the day the HVAC contractor came out, he hooked up an amp meter to the overcharged condenser and saw that it was pulling 24 amps with all of the 8 indoor units running full blast at 64 degrees. When he took out the 3 lbs of refrigerant the amps dropped to 12. Then when we set all of the indoor units to 75 degrees, the amps dropped further to 6 and then at one point it hit 4.5.
The contractor also mentioned something about the overcharged system hitting 500 psi or something and that it was really high.
Anyways, just thought I’d share this information with anyone who has an HVAC system that is performing poorly in terms of energy usage or if some of your units are short cycling. The only reason I stumbled upon this problem was because some of my indoor units were short cycling and on of the LG technicians suggested that my system might be overcharged with refrigerant. With excess refrigerant, it has to go somewhere and if it runs up into other units, it may cause the units to turn on when it senses the temperature difference in the line.
I’m still not 100% sure if this has solved my short cycling problem. I’ll have to wait until winter time to find out. But it sure has reduced my energy usage.
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