BDrivenByDemons
Member
I have a 2500 sqft concrete basement floor that I insulated and pex'd before the pour. I have foam and that double foil bubble radiant insulation under it all. Even brought it up the edges of the poured walls 4 inches above the footings (the concrete crew thought I was insane but it's one of those things you can only do once). The pex is on 8 fairly equal length loops, spaced about 8 " apart, coming into a manifold with 1" pipe connections. I tried to balance my loop lengths while kinda sorta creating square zones but my goal was a balanced system not zones. The basement is wide open. No rooms or partitions and it's staying that way as long as I'm living here. Even though it's a big area I feel like I did an exceptional job with the insulation and want to try and use my water heaters to warm this puppy up...
I installed 2 state power vent 40 gallon heaters instead of one bigger tank thinking I'd be able to keep the family with hot water even if I had a failure of a unit. They are piped in parallel currently and it's got me thinking...
I know I'm going with the closed flate plate exchanger setup. I could keep the parallel piping arrangement and feed the exchanger with some nice hot water and let the system cycle using pumps as things heat up and cool down but I had a thought.
Say I re-pipe the heaters in series. Set the first one anywhere between 80-100 degrees and only feed the exchanger from that unit and just let the pumps run constantly. I'd adjust the temp as needed to maintain a comfy floor. Or even cycle the pumps based on the concrete temp. Then feed the second unit from the first and crank it to 150 or even higher to kill that legionella bacteria and temper it with a mixing valve before feeding it to the fixtures.
Here's my thinking... The second scenario would eliminate the cycling of the system at the expense of being able to change temps quickly. I don't care too much about that. I want a comfy floor that doesn't chill your feet. I don't need to be able to run down there and try and recover a cold floor quickly. The floor temp would basically be controlled by what I set the H2O heater to. Even if I did want minor control and used a thermostat on the concrete surface to energize pumps it would still cut the cycles of the system way down. I also feel like the entire floor temp would be more consistent.
Tell me why I'm wrong. I can't see any reasons this wouldn't work.
I installed 2 state power vent 40 gallon heaters instead of one bigger tank thinking I'd be able to keep the family with hot water even if I had a failure of a unit. They are piped in parallel currently and it's got me thinking...
I know I'm going with the closed flate plate exchanger setup. I could keep the parallel piping arrangement and feed the exchanger with some nice hot water and let the system cycle using pumps as things heat up and cool down but I had a thought.
Say I re-pipe the heaters in series. Set the first one anywhere between 80-100 degrees and only feed the exchanger from that unit and just let the pumps run constantly. I'd adjust the temp as needed to maintain a comfy floor. Or even cycle the pumps based on the concrete temp. Then feed the second unit from the first and crank it to 150 or even higher to kill that legionella bacteria and temper it with a mixing valve before feeding it to the fixtures.
Here's my thinking... The second scenario would eliminate the cycling of the system at the expense of being able to change temps quickly. I don't care too much about that. I want a comfy floor that doesn't chill your feet. I don't need to be able to run down there and try and recover a cold floor quickly. The floor temp would basically be controlled by what I set the H2O heater to. Even if I did want minor control and used a thermostat on the concrete surface to energize pumps it would still cut the cycles of the system way down. I also feel like the entire floor temp would be more consistent.
Tell me why I'm wrong. I can't see any reasons this wouldn't work.