Hi all, Last year around this time we had our oil boiler removed, radiators removed, duct work installed, and Geothermal put in. Without going into too many details about the install quality -lack thereof- I've had questions from the start as to the power consumption, airflow, water intake temperatures and size of my system. It may be all a/ok but my gut is telling me something isn't quite right. Per the tagged thread here is some of the info I do have to start. Apologies for the long read, any help or opinions would be appreciated. 1) Where you live : Allentown, PA 2) Heat loss/gain calculations for your home: No idea, installer may have those? I believe they were based off the BTU# on my oil boiler (50,000BTU). 3) Brand, size (model) and type of heat pump: Climate Master Tranquility 27. Two 2 Ton units one combined air handler & pump for first floor and one compressor with lines leading to air handler for second floor. 4) Type of loop field (open/closed/vertical/horizontal) size and design parameters: Closed loop, Vertical, 4 holes appx 280 feet deep each. 5) Average cost/Kwh of electricity and consumption: Impossible to calculate as a 15.86kW solar array was installed a few months later and two electric vehicles were purchased. (I did not have a comparison year-year vs the oil boiler) 6) Entering and leaving air temperatures (EAT, LAT) measured immediately upstream and downstream of the heat pump: Varies but I am seeing a 20 degree rise when heating intake vs output. 7) Entering and leaving water temperatures (EWT, LWT) measured at the heat pump(s): Also varies but usually a 5 degree difference between EWT and LWT. Lowest temperature measured 30 EWT, highest LWT in the summer was 80. 8) Percent of load to be covered by geo and balance point: Expected 100% by Geo, occasional but rare instances when AUX needed due to old construction, wind. 9) Installers assessment of your systems operation.: Claims everything is A-ok 10) Projected operating costs, actual operating cost and previous heating and cooling costs: Unknown My main gripe is with the water temperatures mainly the way the loops were done. Obviously the lower the EWT when heating the less efficient the system is and inversely when cooling. In my area the water table is at 110 feet down (verified by my well head which is only 50 feet away). This should mean that the system is in contact with at least 170 feet of liquid saturated earth. My concern is that due to the design of the manifold the vertical loops are not being used equally causing one to be utilized more than the others. Also the entry location is only about 2 feet or less below ground level. I've attached a pic showing the field entry point. Note the basement window in the upper left corner (it is in a window well appx 1 feet deep). To the right is a self purging flow center with separate pumps for each heat pump. I do not know the flow rates and they are not listed on the side of the pumps only the Hp and wattage draw. Despite repeated attempts to get the HVAC company that installed the system to come back and install a new manifold with flow meters and temperature gauges (at my cost) they have yet to even provide me with an estimate. My feeling is they have no interest in installing any new equipment that would provide proof that something is wrong with how the field was done. I'm hesitant to call in another company as the first company would just claim whoever came after them must have screwed it up. Obviously as I cannot get them to install gauges all my temperature readings have been done with a thermal gun into the flow center.
Steve: Hello and Welcome. I am going to take your post as you wrote it and tell you what I think. I am a "wet head" I would rather move heat with water than air, it takes up less space in the building. So I would have used your radiation delivery rather than take it out. Unless your wife hated them, then I would have tried to keep the pipes and give her choices. Long reads are not a problem, you caught me on a long write night. The biggest issue is a heat loss/gain number. What size does the programs available tell us the equipment BTUH needs to move. We can still do that. Since I use water to move heat you might have two air handlers, but only one heat pump. The job is what is is, so lets look at what it is and make it be all that it can be. Climate Master is good equipment depending on the install. Your air delta T is OK. Your loop numbers look OK from Cleveland, OH ,this winter. There is antifreeze in the loops or the HPs would have tripped out. The FP1 junper has been cut. If you are not happy then I do not care so much what the installer thinks is going on. Lets get this thing making you happy. We will fix any fuel cost issues as we go. Your loops would be long enough here and you are south of us. I do agree the the near machine piping is not to industry standards. One can only move so many BTUH though a given size pipe. It is tough to gauge pipe size when wrapped in insulation. It looks to me that the brass elbow that enters the machine un-insulated is 3/4", the size should be stamped in the casting. In fact to handle the four tons of equipment, which is 48,000 the manifold needs to be plumbed in at least 1" pipe to the individual pumps. I do not see the pumps or any flow check valves so I can not address any flow issues. I hope this helps. Mark lake-erie-indoor-air-services.net
Four vertical 280' holes and you're seeing 30' EWT with only 4 tons of equipment? I'm no expert, but that doesn't sound right at all. You have nearly double the required loop field for a 4-ton unit. Standard spec around here is about 150' per ton.
I have seen worse inside work.... I will assume Allentown is firmly in bedrock territory for drilling, sooo rules of thumb from other places are sketchy guesstimates at best. The water table in a rock bore is really in material as the rock is a awsome conductor. I am not a fan of flow meters and temp gauges. I am a fan of data collection. If your unit is equiped with PT ports you can gather this data at the machine via probes, or get close with external sensors. Given the nature of this winter, if your inside comfort level is good, capacity of the system is prolly fine. It just needs some tuning to get it in line. Eric
Mark! Thanks for the reply. I agree with your position regarding keeping the radiators and using them to heat. Unfortunately they were in a condition that they could not be trusted and also were in the way of the air ducts. Being that we were going for central air conditioning at the same time removing them was a necessary course of action. The reason for a separate pump and separate air handler for the upstairs was due to there being no clean way of getting a large enough supply and return to the second floor. Compressor lines are small enough that they could be run without adding bulkheads. Another plus being that should one heat pump or handler fail I have the other to utilize until repairs can be made. The two separate heat pumps share a common ground source closed loop. You are correct about the jumper being cut and antifreeze being in the loops though I do not know the brand/type or the percentage. I do know that it is blue in color. My apologies for not including a picture of the flow center or including pipe sizes. Photo4 is the label on the side and photo5 should give you a better view of the valves & pumps. I agree with your assessment thus far. In fact when the loop field was designed I asked the installer to "overkill the loop field size" as I wasn't concerned about spending a few thousand more on an extra vertical hole vs having to re-dig and fix an undersized field later. They originally planned on 3 vertical loops at less depth. I checked the piping size and took a few more pictures. The brass elbow entering the flow center is 1 1/4", the valve for each incoming loop is 3/4", and the valves on the intake and return for each heat pump is 1". There are two brass swing style check valves, one on each heat pump's outlet side. Each heat pump has its own circulating pump on the flow center. I've also added pictures of each pump's tags (photo6 is downstairs photo7 is upstairs). Interesting thing to note and something I hadn't noticed is that above each label is another "www.geoexchange.org member" Is that a label that comes on all ClimateMaster units or would that be something the installer would have added? I don't see the company who installed the system listed on the service providers portion of the website. Here's a link to the type of balancing manifold that I had requested they install (again at my additional expense) as I feel that one or more verticals are being utilized more than the others. There's really no way to tell how much water is circulating in each hole in my opinion. I really appreciate the time spent helping me thus far! -=Steven Bowen
My question would be. What leads you to believe that the loops are not being used equally? If you are baseing that swag on the loop temp, you may be on a fools errand without the design data used for your systems design compared to this winters actual data compared to other closed loops in your area. A quick look araound the geo monitoring site would go a long way. It is also common knowlege that adding an extra loop or two only effects operating temp of the system by a couple of degrees. What do you expect the loop temp to be ? Eric
Steve: One needs to be careful when drinking beer with factory reps. I mentioned to the Caleffi guys one night about 10 years ago how I was using radiant floor manifolds to manifold my geo systems. The manifold shown is my product of choice. It came out a few years after that beer. It is possible to retrofit the manifolds and upgrade from the PVC units to what you wanted. I would caution that when sizing the flow meters that one pay attention to the CV of the flow meter so it does not reduce the flow in the system. When Mtrentw and I used them in his system in MD we went up a pipe size on the flow meters. I feel better about the piping and the general installation when viewing the additional pictures and the reported pipe sizes. More good design went into your system than shows to a note pro. The installation of the TTS ( the attic split system) unit in the basement with the TTV allows the use of the non-pressurized flow center. Both units can be supported using 1" pipe to and from the flow center to the heat pumps. In fact at two tons nominal they could have used 3/4" and gotten away with it, I like bigger piping. Here is a link to your flow center: https://www.bdmfginc.com/BDPdfs/EA-KFC-INSTALL.pdf The first page will show you what your pump curves are in FIG 1. Note that stacking increases the head curve but not the GPM curve. So we know that each machine wants 3 gpm per ton so 6 gpm each. We have that easy money. Now come the difficult part, what is the feet of head caused by the system? We need to look at what is in the system for the pumps to fight. We have the machines and there should be a chart in the I/O manual that gives us pressure drop of the fluid through the machine at various EWTs. Using pressure gauges in the peet's ports, (which you have) at the machine we can convert the psi drop to feet of head. Now we add up all the piping we are pumping through and factor in the fittings and take that number times 4.2' of friction head per 1oo' of pipe. That answer plotted on the pump curve at 6 gpm falls under the curves you have enough pump. Since I know how to do this equation I do it and buy one pump. I also treat my piping like any hydronic system and add all the bells and whistles included. I will be happy to get you stuff to work with your peet's ports. You have half of what you need to measure system performance. Your point and shoot IR thermometer. They do not like shiny surfaces, so pick spots to shot and paint them flat black. If they will tell you a non-customer, ask the former oil supplier for an average gallons per yer of what the house used. I can convert that to BTUH per winter and we have our heat loss. Some home work since the swing checks are in a vertical position, the arrows on the casting must point up for them to work. Water is lazy and takes the path of least resistance. Water is not like Robert Frost. You can drip a bit of loop fluid on a test strip to find out how low you can run your EWT. I can send you some with the peet's ports probes. Since the glycol I use is blue and the methanol I use is clear. You have glycol. Trent's is green. In summery we are doing well. Plumbing was done by a very highly skilled craftsman, who executed a very well thought out design. You report that the system works. So what remains is your ability to "see" what is going on with the system. I am with Water Pirate, who owes me a beer, we collect data the analog way not the NSA way. asking Google. So if you add the ability of taking pressure readings to your test equipment the only thing you will not know is the flow through the loops past the manifold. There are very many ways to gather detailed data, but that is for another Sunday afternoon not in football season. Go Browns. I hope this helps. Mark 440.223.0840
Balancing loops simply means collecting less from one that is performing better than others. I think your installer doesn't want to come back and change stuff is because your system is working fine. I certainly would not wish for my clients to start choking flow through loops I installed. Standard design temps are 30 to 90 and this year was extra cold so it wouldn't be a suprise to see loops under 30 in my AO. Check out "Is your engineer dumber than a bag of rocks" http://earthsensitivesolutions.blogspot.com/ it is a PE's perspective on loop balancing.
I've learned to love 30* entering water temp. In my first winter, I was very concerned that it was in a terminal nosedive, but through the remainder of winter #1 and now most of winter #2, I did some engineering analysis and have come to the conclusion that 30* is about as low as it will reasonably go. I have had some 28* days after persistent polar vortex and stage 2 runs, but always back up to 30-32* steady lows. Even if flow among the four loops is not exactly even, as long as there is some nominal amount of flow through each, the lower flow loops have better recovery and higher flow, not as much, but the streams mix and balance out. Ideal would be equal flow in all loops, but that is only possible in simulations.
I hope the replies have quashed your concern that corners were cut. While I might do things differently, there is more than one correct way. Personally I wouldn't want a manifold inside because that's many more opps. for leaks.
Just for the sake of argument I've been looking into a Welserver monitoring system to better gauge my temperatures over the course of a year. While browsing around I stumbled on a house not far from my location with an almost identical setup to mine. 2 Climatemaster 27s one combined, the other split with a remote air handler. His wells are slightly deeper but only half as many (2 at 320' vs my 4 at 280') With his house at 70 degrees and his desuperheater hooked up (mine is not) his EWT is 42.8, LWT 40.0. Looks like both pumps running stage one. These portals update in real time so the numbers displayed when you click may be different. http://www.welserver.com/cgi-bin/show/WEL0488 West Chester PA is about an hour south of me. So... Smaller field, higher interior temperature setting, desuperheater running, vs larger field, lower interior temp, no desuperheater hooked up. Granted he's an hour south and perhaps his house is better insulated but 10 degrees? I intend to move forward with the Wel system unless anyone knows of a better data logging system? That way I'm working with the same temperature reading equipment and can get as close as possible to a even comparison considering what I just discovered. Still thinking the loop lines enter the house too shallow and are possibly also too shallow in the yard.
I would be careful as comparing apples to apples. In some of the sensors/programs I have used in both the residential and commercial control systems that i have been involved in, is that the placement and calibration of sensors. If they are mounted on the outside of HDPE pipe, and how they are insulated will give you a different number if put on a brass fitting and a different number if on the copper inside the cabinet, and finally a different if you put an inline submersed sensor. Also, we have calibrated sensors and put offsets in the program to display a different value, but also have noticed that the resistance of said sensor is not linear and offset might be right at 40F but different at 75F. Lastly, the house you are comparing to may not have the same load as you. I have seen some systems in my area that may have a 5-ton load but a 6-ton unit put in and a 6-ton loopfield. The 6-ton may actually cost more to run, but the ewt numbers may appear to be "better"
"So... Smaller field, higher interior temperature setting, desuperheater running, vs larger field, lower interior temp, no desuperheater hooked up. Granted he's an hour south and perhaps his house is better insulated but 10 degrees?" None of this means anything without the context of heat load, loopfield depth etc. The WEL is a good product, but blind (meaning not equiped with all the details) comparison will get you nowhere. You might also be interested to note that West Chester College has an undersized loopfield as they didn't figure on cooling requirements year round. They have literally impacted local ground temp. You can take comfort in the fact that the pros here are not distressed by the appearence or function of your system (based on information you've made available), or you can continue to believe your installer "cut corners". That doesn't mean you won't benifit from monitoring equipment, simply that you may find everything is fine.
