Virginia full retro install cost seems high?

Discussion in 'Quotes and Proposals' started by wildwolf, Apr 11, 2020.

  1. wildwolf

    wildwolf New Member

    Thanks for the info.

    Back to my geothermal installation, I think the system is coming along well. The 3 well loops (1.25" pipe) were all attached together via 1.5" pipe with T connectors and brought through basement wall. The lines were then routed up (2 90 degree joints) in wall to the drop ceiling area and then routed to the pumps (via some long connecting pipes & 3 more 90 degree joints), then split via connectors to both of the pump things mounted on the wall to feed each system. I think with a little more careful planning up front, they could have avoided 2 of the 90 degree bends. I mentioned that I wished it'd had not needed those last 2 bends (if they'd brought over the lines 3-4 more feet in drop ceiling, they could have avoided the additional bends), and the installer said he's had installs with "many more 90 degree turns than I have" and those systems worked great so he doesn't think I'll have any issues.

    They finish the tie-in today, start fill up tomorrow with the rest of the HVAC crew, and tomorrow starts the rest of the system installations. I hope they'll finish by Friday COB, but it will be tight now, I think.
     
  2. gsmith22

    gsmith22 Active Member Forum Leader

    I don't know the lengths involved, but would have expected 2" header pipe with a two system setup as flows for a 6 ton (total) system would be on the order of 20gpm. 20 gpm through a 1.5" pipe has a much bigger head loss vs. 2" pipe. There is another thread on here that I was responding too that had a really long run to the field and they used 1.25" header pipe. that one definitely needs 2" pipe (at the minimum). take a look at geo-flo's design calculators and search for multi-unit, distributed pumping system to input your system parameters and verify head loss with pipe sizes/pumps. Efficient water pumping is the holy grail of these systems. There isn't a penalty other than material costs for putting in larger pipe upfront. You will pay for higher pumping costs every month for the life of the system and thus reduce your system efficiency as a result. Not saying this is making the system unworkable or breaking the bank (don't know all the system parameters) but probably isn't as efficient as could be.

    Edit: found this table which will be approximate and certainly correct from order of magnitude perspective :
    www dot engineeringtoolbox dot com/pe-pipe-pressure-loss-d_619.html

    Notice how at 21gpm in 1.5" pipe there is 2.9ft of head loss per 100ft and at 2" pipe this value is 0.83ft of head loss per 100ft. At these max system flow rates, pumping requirements are way higher with 1.5" header pipe. Now this is at 68 deg F water and your loop will be a lot colder with some type of antifreeze so the absolute numbers will be higher. But I wanted to show how a seemingly small difference in pipe diameter at high flows can have a huge affect on system operation
     
    Last edited: Nov 11, 2020
  3. wildwolf

    wildwolf New Member

    May be 2. I’ll confirm tomorrow when they return.
     
  4. gsmith22

    gsmith22 Active Member Forum Leader

    nominal pipe size should be on the side of the pipe
     
  5. wildwolf

    wildwolf New Member

    It’s got a thick insulation sheath on all the inside line and all the outside line is already buried.
     
  6. wildwolf

    wildwolf New Member

    I emailed him. He replied that the line coming in is 1.5”.
     
  7. wildwolf

    wildwolf New Member

    Also, too late now. All the lines from wells to house/pumps finished today. They will tomorrow and start connecting the rest of the systems up. It’s 3 vertical wells at about 330’ deep each. They are all within 50’ of the house and maybe another 50 feet back to utility closet.
     
  8. gsmith22

    gsmith22 Active Member Forum Leader

    those are about the same lengths in/out to the field as mine. I have 3 - 400ft wells so I have more pressure loss in the vertical wells than you and I have a 3T and 4T unit so slightly more pressure loss through the heat exchangers as well as the overall system because my max flow will be higher with everything on. All those things should make my installation have more head loss compared to yours. I didn't see anywhere what flow centers are being used in your system. I'm guessing single speed units given the use of 3 and 5 series WF units. WF typically specs either a single UPS26-99, single UP26-116, dual26-99s, or dual 26-116s. The 26-99 pumps are more efficient than the 26-116 pumps so if you can get away with one 26-99 per heat pump you will have as efficient a system as you can get with fixed speed flow center pumps.

    What I wrote above about more energy use with 1.5" vs 2" header piping isn't correct for a single speed flow center pump (it would be for a variable speed flow center). With a single speed flow center, it operates at the pump's set speed using a fixed amount of power (variable speed can ramp up and down with unit speed causing power use to go up and down). What will change for a fixed speed pump is the resulting flow in the system - more flow in a system with lower head loss (2" header) and less flow in a system with higher head loss (1.5" header) for the same fixed speed pump. So with a 1.5" header, you should expect lower flow than if you had a 2" header. As long as whatever flow is produced meets the unit's flow needs, then none of this matters. geo-flow's design calculators would be where you could figure out the smallest pump size needed for your installed piping.

    Note, most installers and WF don't "design" any of this. Apparently water flow is Greek to them and they like to focus on unit efficiency. We pay for system efficiency so I would make water flow a priority. They like to throw power at the system so they don't get a callback (more power more flow so heat pump is happy) but that ends up costing you more on your electric bill forever. The key is to use only as much pump as you need to minimize power used to pump water around. WF sent a two pump flow center system for my 4T unit stating that was what their standard was. I politely told them to take out the second pump and put a plate over the flow center opening because I had used the geo-flo calculator to determine that I didn't need the second pump. Shockingly (not) the system works as predicted by the geo-flow calculator.
     
  9. wildwolf

    wildwolf New Member

    Geolink flow center FC2-GL on the 5 series and FC1-GL on the 3 series.
     
  10. SShaw

    SShaw Active Member Forum Leader

    You should have a pressure drop calculation done. I think you should be able to run each heat pump with a single-pump FC1 flow center, unless you have very long piping inside or something.
     
  11. gsmith22

    gsmith22 Active Member Forum Leader

    You got the WF "standard" like me. Fc2 has two 26-99 pumps and fc1 has one 26-99 pump. They are both the same flow center body that can use either 1 or 2 pumps with the fc1 just having a plate over the second pump opening. Geo-flo makes them for WF so using their calculator is easy. Multi-unit, distributed pumping is your system layout in their calculation page. I'd run a calc to see if you need the two pump flow center - I doubt it like SShaw says but check the math. Its easy to remove and put cover plate on now but more trouble once loop is full and pressurized. The 26-99 can be set to run at 1 of 3 fixed speeds using 150W in speed 1, 179W in speed 2, or 197W in speed 3.
     
  12. wildwolf

    wildwolf New Member

    They need to come back Monday to finish up. A snag here or there all week caused a bit of a delay in finishing. However, the basement series 3 system is up & running. Water from loop was 57.x degrees. They tested pressure from line going in and it was 39, line coming out was 31.
    Not sure how to convert that to GPM, or if I need to. It was putting out 95°F air at the furnace. I checked a couple vents and was getting about 78-83° out of them. Could have been more accurate, as I was just using a hand-held laser temp thing. The thermostat line from the old furnace is old, so they couldn't mount it there yet. They didn't bring additional line, but will do so on Monday. The upstairs unit had an issue with electrical wire they ran to attic, so they'll be running a new line I think is what they said. They can "power" the units, also, but cannot hookup/turn on the "electric auxiliary" heat, as the electric service still needs upgraded for that. Buddy of mine installs propane and NG generators for homes. He says I probably don't need the 400 amp service upgrade. The geothermal folks say I do. Geothermal folks are footing the bill for the upgrade - it was initially stated it wasn't included, but then they indicated they would cover it to get my business.

    So far, I'm liking the new systems. Little more space taken up in the basement utility closet, but seems to be heating with ease (granted, it's only 48° out right now). Also, they dropped/broke a thermostat and will be bringing a new one Monday to replace it. They are using Lennox iComfort m30 units. Any comments/concerns on those? Quote was for 2 WiFi Water Furnace Thermostats, but I'm not sure if I should press the issue since I know nothing about either (other than iOS reviews of both are not stellar). However, looking online, it looks like the WaterFurance units with Symphony add energy usage stats like compressor, fan motor, aux heat, loop pump, and total energy wattage. Is that something I would want handily available?
     
  13. SShaw

    SShaw Active Member Forum Leader

    A pressure drop of 8 PSI indicates a flow of about 8 GPM.

    WF does not have a "WiFi" thermostat exactly. They have the "Symphony" platform with the "Aurora Weblink" (AWL) option, which is a WiFi box that connects to the control board on the heat pump. You would need one AWL box per heat pump and the Symphony system would have a dashboard with a separate screen for each unit.

    The monitoring feature on Symphony is excellent, but requires the heat pump(s) be ordered with the performance monitoring packages (energy and/or refrigeration). This is an option on the 5 Series but not on the 3 Series. What is the 5 Series model number you have? That will determine what monitoring options are included.

    The 5 and 3 Series can take either a conventional thermostat or the WF proprietary communicating thermostat. You would need the communicating STATs to integrate with Symphony and the monitoring system.

    upload_2020-11-14_8-51-50.png
     
  14. wildwolf

    wildwolf New Member

    I haven't looked on the unit, but the quote says the 5-series model # is: SAH048151.

    After everything was installed, I'm still sitting about 8-9 GPM pressure drop.

    After a little time, I think I'm okay with the wifi thermostats they have provided from Lennox. I guess I won't get to see all the cool stats from having Symphony.
    Also, I just now saw on WF website that they are finally advertising the WF 7-series split units. I hope (my age?) I never have to replace the 5-series I have, but if I ever do, a 7-series is going back in. :)

    The insulation team finishes up tomorrow with all the insulation/envelope sealing we've had done, so starting next week, we should be much more comfortable at a MUCH more affordable price this winter.
    I do know that with ~30°F temps outside, the temp on thermostat dropped from "make it feel like 72" to "feels like 69" when there was no insulation in the attic for the last 6 days on the main floor. The basement kept up fine. Now, it's currently 29 out and the system is able to keep up so far w/o insulation - but there are still about 8 more hours of no sunlight for it to potentially drop. Today, they spray foamed the basement rim joists. In one cold spot in the kitchen, we had a cantilever bay window. The floor was about 60 degrees, and tonight, it's maintaining 69-70, so that spray foam stuff is great! If I ever have a house built new, it's definitely going into it everywhere before drywall.

    So, I must say, thus far, I'm glad we done these 2 projects and will be moving onto the 3rd project soon. Believe I found a solar company for a ground-based array. Just need to determine what size backup battery we will need for our current usage. Bought a clamp meter and will try to learn how to use it without frying myself in the process. o_O

    Oh, one other thing we're waiting on first before solar, the upgrade from 200 amp to 400 amp service. Geothermal folks haven't hooked up the 'back up' electric emergency heat because said I don't have enough.

    Here are 2 pics (if I can get them added) of the current breaker boxes. 200 amp service with 100 amp split to sub-panel for a detached garage (and a few things from house still). Buddy of mine sells generac generators and says most people don't need 400 amp service. Looking at the available stuff in the breaker box, I can see the need to upgrade, but I have no idea how it's all calculated.
    IMG_2444.PNG IMG_2445.PNG


    Thanks everybody for your patience, explanations, and guidance/suggestions.
     
  15. gsmith22

    gsmith22 Active Member Forum Leader

    I have Symphony - it is okay for the homeowner. Its more geared to the installer for being able to diagnose a problem remotely and for WF to collect data about the performance of the system likely for them to showcase performance and/or help with future enhancements/production. A lot of data it collects is hidden to the homeowner so isn't as useful as it could be to those truly interested. google "welserver" if you want the best/most customizable way to monitor what is going on (full disclosure - I don't have it but looks great on paper. someday...)

    I have an all electric house that worked fine with 200amp service. With just the geo units added, it would have probably still been fine at 200amp service and in fact like you, I ran my house this way for several months before having the service upgraded. A load calculation in accordance with the NEC code showed being over 200amps with this configuration but knowing actual use patterns and using the same load calc, I got near but not over 200amps. Actual use confirmed this and it is clear the NEC load calc is very conservative. No electrical code official or inspector is going to allow you to deviate from what the NEC code dictates.

    With the addition of the electric resistance backup heat in the geo units, there was no way to make the NEC calc even come close to 200amp service. Again doing a load calc with electric resistance heat on (assuming geo units broken down) and using the remainder of the house normally (not per NEC) we were sill over 200amps. So a potential actual use pattern with backup electirc heat (although probably rare) was still going to put me over 200amps. If I wanted electric resistance heat installed, we were going to have to get 400amp service or the building department wasn't going to approve the permit. On paper, I would have been way over 200amps with electric resistance heat. But the electric heat has yet to ever turn on and I don't foresee using it unless one of the geo units breaks down so actually needed the 400amp service is probably a once in 20 year type occurance.

    Ignoring all of this, no building code inspector is going to allow someone to keep a 200amp service when a load calc done in accordance with the NEC shows it over 200amps (regardless of actual use or admitted conservatism of the NEC load calc). I tried to attach the spreadsheet I used to do the load calc but it won't let me. If you are curios to do the same thing I did, I think I downloaded it from Mike Holt's website. do a google search for "mike holt nec load calc" and one of the top results is a web page where the spreadsheet for a residential load calc can be downloaded.

    Edit: just remembered we also were planning a future pool which was going to be another ~80amps or so that would get added to my existing service. It wasn't part of the calcs I was doing for the geothermal but I knew that in advance of the service change so I didn't see a point of fighting with building official now (about actual use/conservatism of NEC load calc) to only have to assuredly upgrade the service later to 400amp with the pool equipment.
     

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