Just got this quote for two 3 ton systems. This also includes the removal of all my current AC equipment. Does this seem high? Thank for looking guys, this seems like a great community! Quote Below Loop Field Drill 6 vertical bore holes 300 feet deep each. Install approximately 3600 feet of polyethylene pipe. Header the pipe together and connect to the pump kit. Perform all trenching, backfilling and smoothing the ground. Connect to pump kit to the unit with 250 psi rubber hose. Fill, purge and pressure test system. Ground level valve box(s) with three way brass three way purge vales. 2 TE038A (3 ton horizontal, two stage, R-410a, 29.6 EER) Provide 2 UPP26-116F 230V Gundfos circulating pump with isolation flanges 2 Electronic Air Cleaner (2 filters required for 5 ton and up) Add ($) included 2 Hot Water Recovery System Add ($) included Ductwork & Installation & Spray Foam Insulation Move both condensate drain over to the kitchen side of the house. Provide R-6 flex ductwork with duct board plenums where required Secondary drain pain(s) and float switch Included Spray foam insulation provided by Cooler Green Solutions Included ($) $10,107.00 TOTAL INSTALLATION OF GEOTHERMAL SYSTEM $57,382
no, it seems way too low given the amount of drilling they intend to do and the installation of 2 systems. The drilling seems excessive for 2 - 3 ton systems. It probably really ups the energy requirements to pump all that fluid around. I would avoid the UPP26-116F circulator pumps. they are energy hogs. I would have a single variable speed pump tied to the loop system and regulated/connected to both heat pumps to maximize efficiency. flex ductwork sucks - request rigid metal. Don't recognize the heat pump model numbers so can't help with that. There isn't a lot of details and not sure where this is located (montana?) but this quote wouldn't give me a warm and fuzzy feeling. Did anyone design anything or is the contractor just throwing stuff at your house and hoping in works?
This is in Central Texas. The designer seems extremely knowledgeable and is claiming our hot climate needs deeper holes. He did say the worst thing you can do is under size a ground loop and going a little bigger is not a bad thing.The Units are Climatemaster TE038A. He has come out 2 times spending about 3 hours total at my house. He has gone over the design in detail but it seems to exist in his head only but It does seem very well thought out. He seems to know what he is doing but I am no geothermal expert. He is the owner and operator, I've gone to view a completed job by him and it looks good. The ClimateMaster has options for built in variable pumps but he claims exterior pumps are better. He is also doing each unit to a separate geo field, he says it better to have 2 separate systems so if one goes down the other half of the house will still be able to cool. Each heat pump would get 3 300 foot wells each.
Deep ground temp is ~70 in central TX. For comparison, its 55 here in central NJ. There is basically no seasonal change in that once you get 25 to 30ft below grade - which is true everywhere not just in TX. yes its true that you don't want to undersize a ground loop, but your loops seems like they are probably on the order of 2x as big as needed. unless there is some very specific local geological thing that we are missing and he knows about. Unless there is some spacing/distance issue, both heat pumps should be put on the same combined loop system to take advantage of the likely different heat pump usage patterns. Its more efficient for heat transfer to/from ground. If anything, I could see ditching the internal pump in each unit to have a single variable speed pump on a combined loop system for loop pumping efficiency. I can't speak to ClimateMaster so maybe someone chimes in. It doesn't feel thought out to me unless there are details here you aren't describing well. Regardless, the numbers still feel too low for what he is quoting. 6 wells at 300ft each? are oil drillers looking to get into geo work and you are their test project? Seriously, the entire drilling budget would be $50k where I am at.
This is a house in Texas that has 8 tons total 2 HP's, he has 1 well @ 300' per ton. He was also sold the UP 26-116, he spoke at length with Pro's here about changing to the UP 26-99 because they use 30 or 40% more electricity with only 10% more pumping capacity. As I remember it changing after the fact was not worth it, the savings would take a long time to pay for new pumps. As gsmith22 said, it would be more efficient to use variable ECM pumps/pump. http://welserver.com/WEL0043/ Unfortunately the data logger is not working anymore. Are the HP's going in the attic? Hot water recovery, hopefully he is supplying a non-powered storage tank to go before your existing hot water tank. Both Desuperheater's can be connected to one storage tank. Did he figure HP sizing (heat gain) for after spray foam? Maybe get away with 2 @ 2 tons? The price doesn't look too high to me, though here in the north east our prices tend to be higher.
You can get the Climatemaster TE038 with the internal variable speed loop pump (vFlow). It costs a little more than the unit without the internal pump, but the variable speed pump will save you money in the long run. With that much loop pipe, you would want the optional high head loop pump (Magna Geo 25-140 High Head Variable Speed Pump). 1 well x 300' deep per ton of heating/cooling seems about right for your geographic area. https://www.climatemaster.com/downl...-water-source-heat-pump-submittal-set (3).pdf
Due to long hot summer demands for cooling with little demand for heating in Texas (not much opportunity for loop field temperature recovery), 1 well x 250' deep per ton would be a minimum recommendation. I'm a little farther north in central Arkansas (deep earth temp ~62F) and I had my geo wells (3 x 225' deep) drilled and grouted for a little over $7/ft (~$5k for the three wells). I paid for the loop pipes separately, but they were only a few hundred bucks per well.
One thing is certain: (2) 26-116 will not only cost you about 800 watts when running, but all that energy will go into the loop field, further heating it up. If someone is using 26-116 in a geo system, do not walk away....run away! One way to cool the loop down in the summer is making your domestic hot water with a water-water heat pump,
Ha! exactly. no one doing "well thought-out" geo uses a 26-116. It screams I don't really care about how this works so long as it moves water around. For what its worth, my installer tried to push on me a geo-flo two pump flow center using a variable speed and 26-99 in series for a 4T unit I have. Separately, I have a variable speed flow center on a 3T unit. Both units are on a combined ground loop. I questioned the 2 pump flow center decision for the 4T unit especially since the variable speed comes on AFTER the 26-99 (thanks to WF's programming) negating the efficiency of the variable speed use at low flow. They told me that "waterfurnace recommended the 2 pump flow center to us for units 4T and larger". This to me is incredible that no one did any calculations (not even WF) to determine what was actually needed and just based flow center pumping on size of unit. So I sent them friction loss calcs for the ground loop piping showing them that both heat pumps at full capacity could be handled by 1 variable speed pump. I'm quite sure the contractor didn't even no what it all meant. Needless to say, since I was paying for it, I had them pull the 26-99 out of the double pump flow center and put a plate over it leaving the variable speed. It works fine (as predicted by actual engineering calculations). OP, I recount this story only because in my experience, there is little to no thought put into the vast majority of residential systems. Read this board for a while and you will be convinced of it too. Its all rules of thumb, what I did on the last project and it happens to function, etc. The long term costs of having an efficient system can dwarf the upfront install costs if people aren't careful. The industry has a bad rap because of it. Edit: Arkie6 I hadn't seen your reply regarding well depth/one way heat drive to ground from long summer. Makes sense. I'm a little surprised TX has that little winter. docjenser had a good solution with hot water heating using geo preventing some of that heat from going to the ground. The well drilling costs are shockingly low. I'm guessing this has to do with all of the drill rigs and drilling labor in that area. I was more than 3x that cost of $/ft drilling - is this all mud rotary or would you hit rock? Mine was all consolidated diabase for 3 wells at 400' each so that may have factored in too. They actually changed bits after the first hole the rock was so tough. My yard looked like a volcano had erupted with all of the rock dust from the air rotary process.
You are correct, one has to do the pressure drop calculations, and one can increase the pipe sizes to lower the pressure drop, to save the extra pump. I would never put the 26-99 on a variable speed pump. WF now has a different solution, running the 26-99 as the second stage, which is rarely needed. So the solution is better, but not really great. I rather starve the heat pump a bit of the optimal flow in the higher stages, going down to 2.25 gpm/ton. Reducing pumping power is the holy grail of geo design, not many people master it.
My driller used an air rotary machine also. My home is located on the high bank side of the Arkansas River. In my case, I have ~30' of red clay over water saturated black / gray shale primarily with some layers of relatively soft mudstone, siltstone, and sandstone (Atoka Formation in the Arkoma Basin). It was quick and easy drilling. After drilling through the red clay cap on top of the shale, water rose to within ~10' of the surface.
that is amazing about the water rise. I had 400' deep dry holes. the diabase doesn't really fracture so there is limited water movement through it. its not really a problem for the geo because I have extended the bore length to take it into account but its an issue for potable well water. I'm not the original owner of the home, but the original owner told me he had a water witcher come out to site a location for drilling the domestic water well. where he located water they ended up drilling a 590' well that provides only 3gpm. in talking to my neighbors, that is considered fantastic (incredibly). I haven't had an issue, but you are literally sitting on an ocean compared to my desert!
