# Geo Radiant.



## Otobeme (Jul 9, 2015)

6 ton Bosch geo
9kw Electric bioler back-up
Two marathon (one preheat) 
HBX outdoor reset control with radiant cooling capability
120 Gallon Buffer Tank
Back-up cooling coil in HRV (not in pic) 
11 zones
2 remote manifolds

Stopped in today to check on things and grabbed some pictures. Getting close to trim. It will look better when i get all the wiring complete. I have some pictures from last summer of this underground I will post.


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## Otobeme (Jul 9, 2015)

Last summer underground. All loop in each zone are within 10% length of each other, manifold piping always reverse return. 
Mechanical room, middle left. 12" centers in back right bedrooms. 24" in lower garage, 18" in guitar room, no tube in back left wine room or mechanical rm. 6" centers in far back bath. 











All outside walls 6" centers. 










outside walls, 6" center. I put captions on my pics to remind myself of loop lengths.


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## Otobeme (Jul 9, 2015)

Roth panels with 3/8" tubing behind drywall in the ceiling. No rough-in pics. 

http://stampededrive.net/RothDocs/Flr Pnl SubmittalF 12.12.03.pdf


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## Otobeme (Jul 9, 2015)

Getting thermostats, wiring completed today. 





































Here is a basic rundown of the controls and how it all works. 

The 150 set point controller switches the relay box from heating to cooling according to outside temp. This keeps the system either in heating mode or cooling mode. The HBX controller talks to the storage tank, geo and boiler back up. The cooling temp is manually set at 55 degrees and will be shut of if humidity reaches 40% by the thermostat in any zone. The HRV through a humidifier and a dehumidifier will keep house at 30-35% humidity. 

My design temp here is 0 degrees. At 14 degrees stage one (60%) and stage two (40%) of the geo unit cannot keep up with the heating load nor an electrical element (typical) inside the buffer tank will be able to meet heating load, therefor the electric boiler back up was installed. Stage one of the geo unit should satisfy the cooling load (especially with ceiling radiant addition) but if the second stage is needed its energy will be put into fan coil in the HRV. Whenever the geo is running (heating or cooling) it is preheating one of the marathon tanks by taking the energy from the compressor and dumping into the preheat tank. 

These controls will be simplified by the tekmar tn2 control system. That wall of wires, relays, set point controller, hbx controller etc will be eliminated. It will determine the lowest possible cooling water temp staying 3 degrees above dew point by being able to calculate it own its own, where I manually set the 55 degrees on this project. 

There are many things that still need to be worked out and improved on these systems. For example the night temp falls to 53 and the system starts heating but then temps reach 90 during the day, not good or efficient for a slow reacting in floor system. The air gap between the sleeper boards and gypcrete where we are not getting good conduction on wood floors. And many more... 

Any questions? comments?


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