More Energy than a 13 SEER A/C

Discussion in 'Maintenance and Troubleshooting' started by Steve9998, Sep 7, 2013.

  1. Steve9998

    Steve9998 New Member

    I have very high EWT. See attached chart. There are also some strange looking areas inside lower compartment. See attached pictures.

    I did not remove any insulation from the copper pipes, but it appears it was very hot once or more than once. System has had 2 TXV valves replaced and one refrigerant leak close to TXV.

    I have records of kWh used in cooling season before GSHP install and since. The usage is higher by a 1000 kWh after the install.
     
  2. Steve9998

    Steve9998 New Member

    I have very high EWT. See attached chart. There are also some strange looking areas inside lower compartment. See attached pictures.

    I did not remove any insulation from the copper pipes, but it appears it was very hot once or more than once. System has had 2 TXV valves replaced and one refrigerant leak close to TXV.

    I have records of kWh used in cooling season before GSHP install and since. The usage is higher by a 1000 kWh after the install.
    Steve9998,3 minutes ago Report
     

    Attached Files:

  3. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    The colors of the wires for the thermister make me believe this is a ClimateMaster type product. The sensors and the piping should be insulated.

    Who changed the TXVs?

    Mark
     
  4. Steve9998

    Steve9998 New Member

    It is a ClimateMaster with a Bryant model number. A Bryant dealer installed it and the same dealer replaced the two TXV valves.
    There was also a refrigerant leak at one point, same dealer fixed it. But the one photo shows what looks like to ma a big glob of solder
    and I wonder if they restricted the tubing.

    I live in AZ, but it is Northern AZ. Much different than Phoenix. This may help.
    HDD days at Base 65 is 4865.
    CDD days at Base 65 is 655.

    The year prior to the install for the cooling months I used 5100 kWh using a 13 SEER ArcoAire

    I have 2 years of Cooling data comparing the same months and the average use is 6569 kWh (this is with the GSHP)
     
  5. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    It appears to me that you are rejecting the correct amount of heat, and you delta T seems ok at your 14 gpm. So your heatpump seems to be doing fine. YOu reject about 59 KBTU/H, a bit on the low side for a 5 ton at 80 F entering water temperature, but not of too much concern right now. Maybe you don't have the correct refrigerant charge, which might explain the error code 3.

    But it is very unusual that the ground loop jumps up so quickly in temperature and the heatpumps heats up the loop so quickly. You loop is not performing. It appears that you have not enough lenght for heat exchange in the ground. If you have the loopfield of 5x200ft borehole it is for sure not performing. It looks to me like a 2x200ft. My first guess would be that some loops are locked, may be air locked. A high EWT like that would explain the lack of performance and the high electricity bills.
     
  6. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    I am thinking the same as above. Loops seem like they need to be purged again.
    I am assuming you have 5x200' boreholes with 400' of pipe in each correct?
    Not 200' of pipe for each circuit I hope.
     
  7. Steve9998

    Steve9998 New Member

    Yes, Exactly Right. Of the five holes one collapsed at 170 feet roughly. They said no "big deal" and cut it off.
    So to be perfectly accurate there is 1,940 feet of pipe in the ground.
     
  8. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Try purging, the 60ft lesser pipe in not enough to throw the whole loopfield off.
     
  9. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    I offered my thoughts at the other site Steve has inquired on. Suffice it to say that artificial conditions were created and focus on EWT is possibly a red herring.
    The fact that there is a predicted KW consumption that is essentially 1/2 of actual is the real smoking gun.
     
  10. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    EWT running in the 105-F range in heat dominated climate can explain such inefficient KW consumption, especially a jump from 80F to 105 F EWT within 90 of runtime. It is an indication that there is something seriously wrong with the loop, the refrigerant circuit appears to be reasonable OK under those loop conditions. And that was around 6 am in the morning, where is the loop under solar load at 5 pm in the afternoon?

    Lets say your 3 ton TTV27 Cimatemaster produces an EER around 27 at 67F EWT, that drops down to an EER of 12 at 105F, easily explaining the 50% drop in efficiency.
     
  11. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    I think the loops are a great canidate doc, however, tight loop design with an un common task can yeild terrific temp swings in my experience. We know that you use more than minimum loop design to avoid such that is not true of everyone.
    It would be interesting to know winter ewts
     
  12. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Yes, I like to be generous with loops, but in horizontal designs, where larger loops don't cost very much. The opposite is true for vertical, where I try to be right on the spot, trying to stay right on the 30/90-95F winter/summer rule.
    For a loop to run from 80F to 105F in a matter of 90 minutes in heating dominated climate ....there is something seriously wrong with the loop. In my opinion, loops should not exceed 90-95F under any conditions, even not in heat dominated climate after a how weather span at the end of the cooling season.
    We must keep in mind that the loop with increased temperature in such a short time period simply indicates that it cannot transfer more heat to the ground. Normally a loop shooting up that much creates a higher delta T between the ground and the loop, meaning it transfers more heat to the ground and reaches its steady state or equilibrium. This is not the case here, a clear indicator that the heat exchange between the loop and the ground is not performing. The loop design appears adequate, so flow appears to be impacted. Unless the driller which cut of one circuit forgot to grout it......and there is no grond water.
     
  13. Steve9998

    Steve9998 New Member

    Thank you all for the time you spent on my issue/concern. Not sure there is much more to be said, but based on what I read
    above I have a couple more observations/data.

    The driller mixed (bags of something) with sand & water in basically a large cement mixer. Then he poured it into the hole from the mixer.
    I have since learned one should use a treme tube and pump it to the bottom.

    I have the data from my utility company and during the CDD days (I know redundant) my kWh before GSHP = 5100.
    The kWh are for the two years since the GSHP are 6572 and 6473 (it was suppose to go down). Our usage patterns have not changed a single bit.
    Those CDD comprise about 4.5 months around here.

    Thank you all again and if someone wants to tell me how to close out my post I will.
     
  14. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Have your loops purged, best case scenario there is air in. Worst case scenario, the grout was not filled in from the bottom up and there are large cavities without ground water. Don't even think about it until you have your loops purged.
     
  15. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    Your driller mixed the grout with sand in a cement mixer and dumped it down the borehole from the top?
    Who purged your loops? The driller or the HVAC installer?
    How was the loopfield tied together ( reverse return, close header, or in series)?
    I would recommend have someone purge the system with a Well built purge cart first. Hopefully it is air locked and only using maybe 1 path.
     
  16. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    http://welserver.com/WEL0478/

    Here is a nicely responding loop to a 6 hour stage 2 cooling call. 3 ton hydron, 2x200 ft drill. Loopfield jumps up from 54 to 71 F within 4.5 hours and then stabilizes, goes into a steady state for the last 1.5 hours. House has a lot of solar gain, one of our "warmest" loops at the end of the cooling season. Highest EWT was 71F

    For your loopfield to go up 25F within 90 minutes, there something seriously wrong with it. Your Delta t seems OK, indicates that flow is OK and not through one flowpath only,assuming that your refrigerant circuit is OK. I think your loopfield is not well connected to the ground, but give purging a try first. Have the flow checked. Then approach your driller.
     

    Attached Files:

  17. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    http://welserver.com/WEL0663/

    Here is another example, under continues 1st stage for 2 hours the temp jumps from 57F to 62F, the peak of the season! 2 x 300' borehole, 5 ton heatpump.
     
  18. Steve9998

    Steve9998 New Member

    I have said it but will say it again Thank You to all.

    This last very detailed charts and graphs are wonderful. I found another set of data regarding the use of a system over a 24 hour period and the
    EWT change from high to low 7 degrees.

    I did not get to welserver.com today, but my plan is to buy the logger myself regardless. Later I hope armed with the data I will sell it to the
    dealer for him to use.

    And yes the driller did pour the mixture from the mixing device into a large funnel shaped piece of plastic stuck into the top of the hole. I can even attest to seeing
    them carry a 5 gallon bucket over to the holes when they were close to full so they didn't have to move the mixer. At the time I was clueless about
    how wrong that was.

    The dealer purged the loops, but I do not know the specifications of how many GPM the pump pushed through the field. I do know he spent about 3 to 4 hours at
    most doing this. I do not know the terminology well enough to answer some of the question. So here is my description: 5 bore holes 3/4" HDPE, 200 feet down 200 feet up
    with a connector at the bottom. The five loops came pre assembled like that, then stuffed into the hole and grouted as described. I htink I mentioned earlier that one hole collapsed at roughly 170 feet driller just cut the pipe off.

    Then a trench was dug along the bore hole line (20 feet between each hole). A Tee trench from this trench to the house.
    They took one side of each of the loops in the hole and ran them to a junction point. Connected each one of the five to this connector.
    From this single connection point ran 1 1.5 inch line to flow center. Took other end of each loop and did same thing and then ran
    1.5 inch to other connection on flow center. Pressurized it, it held I was told and all was buried.

    I hope I have answered all the outstanding questions.
    Regards
     
  19. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    how far from the loopfield to the house?
     
  20. Steve9998

    Steve9998 New Member

    Loop field is more or less a straight line from the placed they Teed off to the house is 24 feet.
    Once inside the garage they ran the 1.5 " up the wall and clear around to the other side and then down
    to unit. This distance inside is 48 feet.

    I hope that is clear.
     

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