I'm in process of a total rehab of a house only built 18 years ago that never had AC and the hydronic heating system that was woefully inadequate. So I'm staring from scratch with everything. I'm looking at radiant heat floors including basement and possibly garage and using the geothermal system for AC and heat for upstairs bedrooms only and whole house auxiliary heat when unoccupied. Geothermal system I am contemplating is a pond loop slinky sunk into a 7-9 acre lake with a max depth of 22 ft. I have considered a pump and dump system as I have the benefit of a spring fed pond that never drops level and a 30 ft drop that could utilize a siphon therefore minimal if any pumping required if the line is sized properly. I work on the water and have raw water cooling systems of every sort, strainers would need to be installed and that requires attendance as well heat exchanger can get fouled over time although I think at a far lesser rate than seawater. My concern with using the pond for heat is that I don't think it will be as efficient as a ground system and if I have to spend extra money for a radiant water heater. Maybe I'm being paranoid but I was thinking high efficiency oil as a good option augmenting water heat in winter and if I start heating a garage and basement floors and possibly a deicing system in areas it may be a bit much. I do know the pond springs are cold as even in the warmest days it was chilly swimming. I'm using the best insulation throughout closed cell foam right to the rafters. Also since I'm putting additions on two sides of the house and want to put all equipment together I was thinking of burying the pond loop lines into concrete crossing the house to where I want to position everything. Any problems foreseen with doing that? Any thoughts are appreciated Thanks in advance
As I'm re reading and it was late I think I may have confused my concern. Would a pond loop and geothermal radiant heat system have the capacity and be worth the effort for a primary radiant heat system supplying hot water as well in the northeast? I have an existing old school boiler from the late 90s I could set up for use in emergency.
That could work. I do geo to radiant all the time. We are having a pond loop school Sunday in Ashtabula, County, Ohio. Mark
.....more thoughts: Moving heat is what we are typing about. All the heat we are moving comes from the sun at some point in time. It is a matter of when and what the storage device is, IE: coal or fire wood. Some one grabbed my ear and drug me to the truck. BRB. Mark
.....well I was not right back. I am attaching some pix of a home and the pond and loops that heat and cool it near Cleveland .
Well that is not a small house and if Effieciency is still good in winter then maybe i dont spend big bucks on a state of the art oil furnace and reuse the on I have. I am putting an addition on two sides of the house basement and main living area on one side, total sq ft 3000 max with basement. i am planning on eliminating the chiminey as it was just a box with pipes but i dont want to build another so not sure if i can direct vent my 98 vintage boiler. i just want a suitable backup in case i loose a compressor or have another problem that downs the heating system. I was planning on a pellet stove set up to look like chimney hearth but it would be direct vent and could possibly be emergency heat but it was primarily for amniance and taking the chill out on milder evenings. I'm pretty handy and mechanically savy but dont have a lot of experience with hydronic systems and cojoining a georadiant with a traditional oil fired unit. guess i will need a little professional help. Any recommendations on equipment would be appreciated since you have probably seen it all. equipment mfr? Compressor types and piping for the loop. And or installers I have a unique property with a house on a spring fed lake with a dam and a 25-30 ' drop so does an open loop make sense? I am a marine engineer of sorts no degree but been doing this my whole life so access to things like duplex strainers, pumps even heat exchangers is no problem. I'm doing the trenching for addition and to the lake so running a 2" PVC to the bottom and into the house could be easily done. I'm looking at a water furnace dealer and there are geoSmart dealers in state as well. Any preference? if i lived a little closer I would definately attend the class Thanks
No reason you would need a backup oil burner, we do geo radiant all the time. It does not matter what your source is, open, closed, pond, they all are designed to feed your geosystem with a certain amount of water at a certain temperature. I like ponds in heat dominated climate since they run warmer during winter due to 39F water being constantly at the bottom of the pond. In other words the pond works more efficient than a closed loop. Couple no-no rules: No open system with the pond, so will have algae, sediment etc plugging up your heat exchanger. Use a closed system. No PVC pipe, high density polyethylene should be preferred. No need for a boiler, your geo system can do it all when well designed. You can run your A/C via air handlers with chilled water in the summer time. But we would need more data: What is your distribution system? What kind of radiant? Where are you located? How far is the pond away from the house. Did anyone ever do a heat loss? Why was the old system inadequate? Here is a loop example. http://welserver.com/WEL0384/
OK Understood HDPE it is I was using PVC as slang is there a backup for the system built in if compressor should fail? I was looking at Water-furnace but local dealer really doesn't want to give any info unless I sign a contract and give deposit. Also is a Pond loop Less efficient in winter due to lower temps? Old heating system was Hydronic boiler with registers, There were not enough to properly heat in winter and the house was abandoned so all the copper was compromised. I cut it all out and plan on Pex tubing Radiant in floors most likely set into a track system and into concrete floors in basement. Located in 07821 area code, pond is 75 feet from house but have some obstacles to overcome, Mainly Bedrock. May have to get a large machine with hammer to make part of the trench. Calcs were started but then the project changed additional Sq ft added and we are changing a lot of windows, adding some and reducing the sizes of others. As far as AC system I want to put air handler in Attic as it is unusable space for the most part, there will be foamed in roof so it will be a conditioned space and with the open floor plan I it will be easy to drop vents into ceilings. More room division upstairs than down. I believe last estimate was a 3-4 ton AC load. Just thought I would throw the siphon dump system out there as it would allow possibly drilling one hole through the rock. I assumed there would be more maintenance but with a decent strainer and back flush system my main concern was the dumping line not being buried and possibly freezing in winter. here is a view from house and pond, where you see the white stone leading to lake is where I plan in trenching. Two obstacles are rock and a Dam so My depth may be limited at some point but I plan on hugging the rock down to the water, Water depth at end of dock is 16' and at end of first section is 10'. Thanks mark
The compressors are usually very reliable. You can use electric heat elements in the buffer tank as a backup if you feel you need the peace of mind. Again, the best is to put a closed loop in the pond. If you go with radiant floors make sure you put them on top of the subfloor if possible, so you can run the supply temperature lower, increasing the efficiency.
That was my plan, any reservations about radiant in basement floors? Any recommended insulation I was thinking the 2" styrofoam and my mason mentioned he had seen a thinner material used with a foil to reflect the heat. I was also planning on putting air handler in Attic and using it for AC whole house and heat only in the upstairs bedrooms and den, does that sound feasible?
No, Radiant is good in the floors. Put the styrofoam under and around the perimeter. The thin foil makes huge isolation claims, but tests have negated that claim. Sure, air handler sounds good for upstairs.
