Question: 1. Would low loop pressure cause excessive electricity? 2. Would low ethanol in the loop also be a cause for excessive electricity consumption? We had our waterfurnace system installed in 2016, about 9 months after we moved into our 2100 sq. ft house. We are searching for the cause for why we have not only received savings switching to geothermal but have had our costs 25-40% higher. We have been back and forth with the installer who has found all sorts of reasons for this problem over the years -- user error is the main one but more recently they have conceded that there is a problem. They blame the drilling company and the drilling company blames the geothermal company. Getting an answer to these two questions will help us with where we are at the moment... maybe more questions to follow. Thanks so much!
Yes if those conditions cause the compressor to shut off for safety reasons and aux/emergency to take over. Why does the loop lose pressure? Could change to a non-pressurized flow center. Why not add more anti-freeze?
Forget pre-install to post install costs ($). Costs vary too much by energy source and even regional variations in energy source. Focus on electric use to see if there is something amiss. If you are strictly comparing electric use (kWh) now vs electric use pre-geo install, then I would have fully expected your electric use to rise. Whether that offsets costs is entirely different matter. my geothermal system uses something on the order of 80% of the electric running the heat pump compressors and something like 10% of energy in the loop pumps (moves fluid around closed ground loop) and 10% in the unit fans to move air around the house. Electric use increased by 7000kWh/year with the geo versus our pre-geo electric use (with propane furnace and traditional air conditioning system). So, absolutely, electric use had to go up but we don't pay for propane anymore so our overall cost dropped dramatically. What ChrisJ is alluding to is that potentially your electric use went up wayyyyy more than anticipated which is almost always the result of electric resistance backup/emergency heat coming on (assuming it was optionally installed) rather than your heat pump's compressor/refrigeration system producing all or most of your heat. First figure out if electric heat is the consumer of the electric. Then figure out why the electric heat is on versus your heat pump compressor.
