Hi - this is my first post here - I apologize in advance for the lengthy post, but I want to ensure I give all the details. I could really use your help and advice. I am a "DIY" homeowner who is new to Geothermal. We had our home built in 2019 - 3250 sq ft in the metro-Detroit, MI area. House is well insulated - spray foam interior, 1" foam exterior. We keep the house at a constant 70*. We've had some significant issues with our builder, and although his HVAC subcontractor seems like a good and knowledgeable guy, I can't help but have some skepticism when my gut is telling me something is wrong with our system. I'd like really like to learn so I am able to troubleshoot and potentially repair/maintain simple items going forward. I don't want to have a service call every time I feel something may be "off". I do plan on having another company come out to inspect it soon but want to have some base line understanding on things. The system is Bosch SM060 on a horizontal closed loop system. Unfortunately, I don't know the length of the loop. From what I can tell, he did install the loops at a good depth - allegedly 6' and from what I saw, I believe it was at least 5' if not 6'. The flow center is a Geo-Flow, model 1333-1391, produced August 2018. It has 2 Grundfos pumps, UP26-116U. The installer used alcohol (methonal?) as antifreeze - I saw him fill the system with it in his flush cart. It should be noted, I am on a well and he filled with unsoftened well water. I have 3 concerns I was hoping this community could help with: 1) We've always been disappointed with the cost to run this thing. I have nothing to compare it to, as this house was never on propane or natural gas. I have a reduced rate dedicated meter and panel for the geothermal. It literally only has the geothermal and the hot water heater on that entire 200 amp panel. I can share a detailed breakdown of run times and energy usage by month. Here's a brief breakdown of our last 6 months of costs and usage (costs are JUST for geo and hot water panel) - does this seem normal? - Jan 2022: $424 / 3,137kw / 648 hours total heating run time, 3 hours on Aux heat - Dec 2021: $270 / 2,021kw / 357 hours total heating run time, no Aux heat - Nov 2021: $257 / 1,922kw / 260 hours total heating, 1 hour on Aux heat - Oct 2021: $157 / 1,166kw /11 hours total heat, 61 hours total cooling - Sep 2021: $157 / 997kw / 11 hours total heat, 88 hours total cooling - Aug 2021: $281 / 1,800kw / 297 hours total cooling 2) One of the flow pumps seized. I noticed last month, in Dec - it was very hot to the touch. I pulled the bleeder screw and the rotor is totally locked up and not spinning. I tried to free it, but it's definitely locked up...bent the flat screwdriver trying to break it loose. Additionally there appears to be a lot of white "scale" on the outside of the working pump. Interestingly, I don't see this on the side of the non-working pump. I've attached a picture below- pump on the left is seized (and now disconnected), pump on the right is functioning and shows the white "scale". Is that anything to be very concerned with? In retrospect I realize this was probably a major misjudgement, but I had disconnected the bad pump and noticed my lights don't dim nearly as much when the unit fires up with it disconnected. Reading a few older threads on here, I got the impression that these are fairly large pumps and some folks have found that running 1 or downsizing actually yields some operating savings. I think I've proven, via #1 above, that isn't the case for me. I'd like to replace it and it seems like something I can do myself. Is this as easy as turning the 2 way valves, unbolting the bad pump, and bolting in a new? I found the same pump online for just over $300 and can order and replace it if it's that straightforward. If it is, can anyone give me the step by step on which direction to turn the valves (they are on the sides of that flow center) to ensure I don't screw anything up? 3) I've had the ground loop topped off once before, by the original installer, sometime during the 1st year it was installed (2019). I recall him saying it was a little low (I had the impression it was marginal) and he topped it off while he was here - didn't indicate it was critically low. I wanted to be able to monitor it, so I bought a loop gooser and just checked it today. While running, on a 20* day here in MI, I am getting 8 PSI on one port (lower) and about 5 PSI on the other (upper). Also, the upper port had a thin layer of ice (frozen condensation) on it. I had to use pliers to loosen the cap to check the pressure because of the ice. To add - I have no expansion tank, just the piping to/from the unit with the flow center plumbed in. Low pressure concerns me greatly - I understand pressures can vary depending on the time of the year, but should it drop this low or does this indicate a leak? Should I boost this up right now with the gooser? My concern there is, aren't I slowly diluting the concentration of antifreeze in the system each time I add? Thanks in advance - I'm hoping with this forum's help I will learn more and become more comfortable and capable with my Geo system.