Results 1 to 10 of 10

Thread: Low water temp

  1. #1
    Join Date
    Feb 2011
    Posts
    3

    Low water temp

    I had a new closed loop system installed Jan 1 in centeral ohio. System worked great the first week and half than the system would lock off with low water temp. The gound loop system is 5 ton for a 2450 sq ft newer house The ground was really wet when they installed it and is in a low lying area. I get about 12 hrs on than I have to shut it down for 12 hrs to emrg heat. Is this normal for a new system? We had a lot of rain after the install and the ground has settled. Any help would be great.

  2. #2
    Join Date
    Jan 2011
    Location
    TN
    Posts
    93
    #1 No this is not normal. #2 If the ground was wet and cloddy whenever loop was installed your ground may not be making good contact with loop pipe, if this a horizontal loop.Your loop could be undersized.Your unit could have bad sensor.Also the geos I work on have either dip switches or jumpers on the control board that have to be adjusted or clipped for a closed loop that lowers the cutout temp.Because closed loops have antifreeze solution in them which will allow water to go below 32* without a problem.If I remember right the adjustment will allow the water to go down to 15* I think.If everything is sized and working properly this is not normal.

  3. #3
    Join Date
    Feb 2011
    Posts
    3
    The jumper has been cut for horizonal I have checked the sensor also, the Bryant rep did that. It only called for a 4 ton but I went with 5 just for this reason. I don't know if the water table in the dirt would freeze faster than if it was just dirt? With the 5 in of rain we have had after the install I would think it is makeing good contact. Thanks!

  4. #4
    Join Date
    Feb 2011
    Posts
    6
    Quote Originally Posted by low water temp View Post
    The jumper has been cut for horizonal I have checked the sensor also, the Bryant rep did that. It only called for a 4 ton but I went with 5 just for this reason. I don't know if the water table in the dirt would freeze faster than if it was just dirt? With the 5 in of rain we have had after the install I would think it is makeing good contact. Thanks!
    First, the cutoff for closed loop should be 18 degrees. Secondly, if it is a horizontal trench, what is the depth ?? Should be at least 5 feet or better. When I install in trench I go 7 feet or better. As far as loops making "contact" with earth, it can take up to a year for the loops to be "set" and producing 100%. Hopefully your contractor correctly mixed the fluid to achieve a specific gravity of approx. 85% in the fluid. And he sized looping for 5 ton. Going bigger on equipment is not the right thing to do unless you plan on an addition. I hope that you got a two stage Geo, if not you have wasted your money on the purchase and money on operating costs.
    Regradless, if your unit is shutting down on waterflow, then you either have a seriously undersized loop field or a refrigerant/expansion valve problem with the unit.

  5. #5
    Join Date
    Feb 2011
    Posts
    3
    Its 6 feet deep by 3 feet wide. Around 450 feet of trenching The unit is a Bryant 50ydvo64 I think its a 3 stage. We have a finished basement that is not in the sq ft of the house a second reason. I did watch them mix it and it has 45 lbs of pressure and the unit has a 5 degree drop in temp form in to out. I just can't understand why it keeps coming back with a low water temp error after 10 to 12 hrs of running.

  6. #6
    Join Date
    Mar 2007
    Location
    Cedar Rapids, Iowa
    Posts
    120
    What type of antifreeze do you have in your loop? If it's Glycol, make sure it is mixed to a 25% level. I'm not sure what levels are needed for Methanol.

    Bergy

  7. #7
    Join Date
    Mar 2011
    Posts
    31

    Got pics

    Could be that the header was installed incorrectly and you are short cycling through only one or two trenches. Without a reverse return header the whole loop field doesn't contribute heat equally to the circuit. You know... the path of least resistance.

  8. #8
    Join Date
    Jan 2004
    Location
    Sanborn, IA
    Posts
    191
    I'd be a little concerned about the loop field being 3 feet wide. 6 foot deep is probably alright as long as it is wet. my "rule of thumb" is to have 12" between each pipe. in the case of a 5 ton/loop system you would need 9 foot wide trench.
    the bryant will have a jumper that needs to be cut to allow for operation with a closed loop, but it sounds like they did that.
    my number 1 guess is a loop field that isn't sufficient. you've got a 2.5 ton loops field trying to feed your 5 ton system.
    Last edited by aaronforprez; 03-22-2011 at 09:23 PM. Reason: clarification

  9. #9
    Join Date
    May 2005
    Posts
    159
    So you described the trench, but you didn't describe the loop. How many parallel runs? What size piping? My gut says you don't have enough loop. Even if he put in 4 pipes into that trench (2 parallel loops), that's only 1800' of pipe. In the end, you're transferring heat to a certain volume of soil, and a single trench that long just doesn't sound like the pipes are run through enough volume. Also, did they ever give you a flowrate for your system?

  10. #10
    Join Date
    Mar 2011
    Posts
    31

    Confused loop size?

    Did you have more than one trench because the max length of pipe is 800 ft. before it need to be tied to a header manifold. if they put 5 trenches 90ft. long with a 6 pipe system you still end up half a ton short, but I'm pretty sure that it would be enough not to set of your flow fault. I install six pipe trenches all the time with each hundred foot trench equalling a ton of capacity. So the minimum trenching you should hae had is 500 feet, plus whatever the header trench took up

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image