Hello, My first post, and I hope I can fill in enough information to get some serious answers from informed people (I've been reading posts all evening and know that this is the place to be). My geothermal system is based on Carrier system 50YEV (http://www.carrier.com/homecomfort/...umps/product---geothermal-heat-pumps---50yev/) and is a closed loop system which stretches horizontally across our yard. We built our 2200 sq. ft. home 2 yrs ago, and when first moved in, the contractor for our geothermal system failed to cut the jumper so the system would work in less than 30° temperatures (closed loop but was setup as open loop). It took me arguing until I was blue in the face before they would send someone to check it. Finally they found the jumper and fixed it, and we've had no problems out of the system during the summer months (The Mrs likes the temp set to 86 in the summer and and 73 in the winter). The problems we currently have is not enough output at the vents, and not enough savings. Currently, our geothermal loop seems like it's frozen (frost build up on the piping in the basement, and furnace keeps kicking over to Aux Heat). The air returns are about 8 ft high and take up 2 stud cavitys in the living room, 2 stud cavitys in the dining room, and then one stud cavity in each bedroom (3 bedrooms) and there is a small return in the basement. If I close the vents in the house in a strategeried fashion, I can get decent air flow to the kids bedroom and to our bedroom, althought other vents in the house whistle. If I open all the vents, we really don't notice feeling "warm" the way we do when they're strategeried. We have two water heaters (one thats wired up and one that isn't) and the one that has no wire to it is suppose to be taking on hot water from the geothermal system, and dumping into a holding tank to be heated again before we shower (I say suppose to because touching the piping from this over to the water heater shell doesn't feel hot at all). I do not currently have the means to take temperatures of air or water and know you're about to ask for them, but I'm hoping to get a couple simple answers on my journey to find the truth about my problems, and their solutions (I will work on getting temperature probes and maybe buy some pete-port guages from internet). 1) I've read a 5 ton system requires 300"cu of return to run properly. I'm told I have a 3 ton unit, does that mean I need 180"cu of return to work properly? From my sorry description, does that sound like proper returns (I had never heard of anyone using wall cavitys as returns, I mean the vent covers are screwed onto the drywall with no ducting whatsoever)? Would improving these returns produce more air at the vents or is my system producing as much airflow as it should? 2) Is the geothermal loop buried deep enough if it's producing frost and ice in the basement? I live in Indiana and today it was a -7° out I know, but I thought if the geothermal loop had been buried deep enough the temperature coming in would have been somewhere in the 40s or 50s and not feel like a creamsicle. Is there anyway to know for sure before calling my contractor and exclaiming "Shenanigans!"? 3) Do you see anything immediately wrong with my setup from the pictures? Our thermostat Unit, water heaters, misc junk Pump Water and Ice built up on pump More water and ice Peeled back the insulation on the top to find frost and water there too! Place where geothermal loops poke through the basement wall and out into the world. More ice here... Wonderful wrapping, insulation job eh (not how I'd do it but they're professionales)? Touching the middle here feels like a nice frosty beer and is slightly wet (followed by the insulation that was touching it). Any information or guidance would be greatly appreciated! Thanks, J
My advice would be to tell your wife to put a sweater on and get a blanket. Turn your thermostat down! Unless your contractor sized the system and loop for 74 degree internal temperature you're going beyond the design parameters by setting it that high. Not enough heat the vents? Well, that's because your loop is too cold. Your loop is too cold because you're extracting too much heat from it. I would set back to 70 degrees (commonly used for design purposes) and see how things progress.
Your moisture is just condensation. You can verify the loop is still pressurized. But you are just looking at condensation. You get more as the water gets cooler. The insulation is to keep the moisture off the pipes. So a bit of housekeeping with tape and insulation will take care of that. Does your system "kick over to auxiliary heat" or add auxiliary heat as a stage of heating? Heat pump + electric plenum heater? If your system can not meet thermostat set temperature within a time frame, it will generally call for additional stages of heat to get there. If it is locking out, and emergency heat is coming on, then that is a different matter.
Thanks for your replies: We turned the thermostat down to 70, but it seems since it's warmed up to not have any problems keeping up on the loop with it set to 73 since it got warmer. I also had others verify the condensation is normal (not that I didn't trust you guys, I just didn't see the replies until just now). Okay, so more digging and more information: We've had problems since we built the house, and couldn't figure out what was wrong. The people who put it in came in and cut the jumper allowing the system to operate on lower temperatures in the loop (we thought it was an open loop versus closed loop thing but I think otherwise now). I spoke to someone who owns an HVAC shop here locally and they were pretty informative about alot of things on our setup. 1) The rough drawing and measurements we did says that my loop is about 300 ft out before it loops over and comes back towards the house. 2) The type of soil our land is sand/gravel and not moist clay. His calculations using the manufacturer supplied planning program says for our soil type the geothermal loop should be a distance of 645ft before it loops back towards the house. It also states the loop temperature should be between 28degrees and 95degrees after it's run through the yard without glycol, and slightly lower with glycol in it. His estimation is that the builder cheaped out and ran 300ft of loop to save money, and that the glycol isn't touching enough of the ground at our pump speed to properly exchange heat. This got me thinking... Was the builder fine in the beginning without cutting the jumper allowing the loop to run colder than 30degrees and the problem is that the loop isn't long enough? The people that the loop was subcontracted to screwed up, and cheaped out and caused us all these problems. Is this HVAC Owner accurate with his information? I've called the loop people and was very friendly, stated we're having yard work done soon and need to know our soil type and how long of pipe they put into the ground and whether it is 2-pipe or 3-pipe. Their initial response was they use 3-pipe (6-pipe total) and bury it below the surface at 3 feet, and then the other run below that 3 feet, but they weren't anywhere near records of our length. I'm going to call the builder today and apologize for giving them the what-for back when and see if I can get them on my side, if someone can confirm I'm not completely off on my estimations. Thanks for the all the help! J