A Miracle at Toad Forest

Discussion in 'General Discussions' started by draginol, May 13, 2011.

  1. draginol

    draginol New Member

    Hi guys,

    As some of you may recall, I've been struggling with my Geothermal setup since last year.

    To recap, I have a 20,000 square foot home that uses 5 Geomax series 2 heat pumps with radiant heat and 5 forced air units. At various times, I've had the heat not work at all, the heat work in some zones only, the heat only use the backup boiler and on and on.

    This Spring, I was able to confirm that, low and behold, the cooling didn't work at all. I had had enough and knew that the existing contractor that had wired the setup was over his head.

    So after posting here, Mark (his wife Steph) and Joe (AMI) contacted me and over a near-week period helped completely transform the setup to work.

    To give you an idea of just how far away from working properly the setup was, there was no way, even theoretically, to make the house go into cooling. Mark and Joe fixed this by setting up a simple "Heat / Cool" switch. This is a short-term solution so that I could get cooling -- and in a nick of time as the weather here has warmed up dramatically just as they finished. They also fixed the 2000 watt pumps to not run if the system wasn't calling for anything (yes, the original setup had the two inner loop pumps running 24/7!).

    They were able to come in, figure out my fairly complex system and get it into working condition in only 4 days.

    Thank goodness for these forums where I could make friends with knowledgeable people. I also was relieved, in a way, to know that I wouldn't have been able to fix this myself. As an EE, I felt a bit guilty that I couldn't fix the system myself.

    I'll leave it to Mark and Joe to give details on the things they designed and implemented (mind you, all this in just 4 days) while here so far.
  2. Mark Custis

    Mark Custis Not soon. Industry Professional Forum Leader

    Where is Toad Forest?

    I never saw a sign that said "Toad Forest", (gives me a great house warming gift idea), but I might down load the camera and post a few of the changes.

    Stephanie and I have never ever met a nicer or more hospitable bunch of trolls, (For those that do not know, in michigan they now have a bridge that connects the mitten to the upper part of the state. I forget what they call the bridge, but I have been over it once in about 1964. The folks that live under the bridge are called Trolls, and the folks that live above the bridge are called Yuppers.) or customers and partners than we have met over the last week or so. I figured if a guy can design and build himself and his family such a tastefully executed home, it ought to have cooling.

    We are birders and took an extra day in the black swamp. We can get here on a day trip. Just for fun I started a day list of those birds I know and I am at about 74. Ha Ha Joe. I know you where working today. Thanks for you, Mike and Chrissey for helping us help Dragon.
    Last edited: May 13, 2011
  3. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Not sure anone will be blown away by our speed on this one (4 days):D:D:D

    The short story of what we did was find away to work with exisiting controls to give Drag control of the system......without a central heat/cool isolating board. Few exist that will handle all our data points (18 different thermostats, buffer tanks, 5 heat pumps, 5 air handlers).

    It appears the original cooling plan was to have Dragin pull the wire in each heat pump that allowed tekmar to activate them to respond to buffer tanks (heating).
    Then use air handler thermostats to activate cooling (each 5 ton heat pump slaved to one air handler).

    What this meant was when cooling time comes if you don't have signal wires from tekmar pulled, you will still be trying to heat the buffer tanks while you are trying to cool a zone (those pumps not called by their air handler would respond to the buffer tank temp drop caused by the unit doing the cooling). Further as heating and cooling stats were seperate you could concievably have a zone calling for both at the same time.....so if you had pulled tekmar control wires, you would then be running chilled water through radiant floors in sticky, humid MI (can anyone say mold factory?).

    Unfortunately to get past this, lots of isolation was necessary meaning (for near term) relays, fan centers, cooling aquastat and air source zone boards to help not only isolate but add timed stage feature.

    End result to switch from heating to cooling one master switch takes us off tekmar control and onto mine (it is also advisable to turn off radiant zone circulators). Throw in some insulation so the pipes don't drip while cooling and we were good. We also reduced capacity by 40% (employed 15 instead of 25 tons) during cooling, as original designer's heat load indicates about a 150MBH load.

    Not a perfect solution, but it could be permanant depending on level of sophistication desired.

    Things that remain to do:
    flush loops (audibly full of air)
    determine if one of the 2 giant loop pumps will suffice (will measure gpm after flush)
    get load side loop circulators to operate intermitantly, and find out if one will do (this has to respond to 3 different taco circulator centers)
    select/install a master control system
    figure out if we can use geo instead of the low efficiency gas pool heater

    I'm sure there's more but it escapes me right now.

    We should thank- Walt the builder, Brad the designer, John the well driller, Walt's site super and the plumber (both of who's names escape me this morning) all of who were available by phone or present on site to answer our questions and help figure out how the system was set-up and how to improve it. It's easy for a contractor or designer to let ego get in the way when a couple of Buttinski's show up on their job.
    To a man all were helpful and soley interested in Draginol's satisfaction.

    Loop flush is next week, keep ya'll posted.
  4. AMI Contracting

    AMI Contracting A nice Van Morrison song Industry Professional Forum Leader

    Loop flush took about 6 hours and most of a drum of premix glycol and distilled (guessing that's what original installer used since it is the preference of his trainer).
    I spent my time wiring load side circulators to run only on demand (from geo or load side stats).
    System is performing satisfactorily to our knowledge, but haven't had any really hot weather yet.

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