Had planned to write a real lengthy update describing the radiant heat system tonight, but I fell asleep during the recorded lecture of my Business Statistics and Analysis class tonight, so there goes the extra hour I had planned to write about the heating. Can you believe that I fell asleep not just once, but three times! Holy geez I wish these classes were a little bit more interesting!
In this overview picture you see our 4 stage oil fired Pensotti Boiler and all the copper/iron piping, circulation pumps, flow check valves, pressure regulators, manifolds, etc. to send water every which way throughout the 5,000 feet of radiant pex tubing within the concrete slab. I think I understand everything that’s going on here and will do my best to convey Gary’s incredible design, but it’s pretty complicated and I really haven’t spent enough time talking to him about this so there might be a few mistakes.
For right now, I’ll just talk about the radiant heat system since this is basically what’s done, and it acts as a closed loop system so for all intensive purposes it is mostly separated from our domestic hot/cold water supply. The system will be charged by fresh, cold water, and then will use the boiler to heat this water to approximately 190°F. The heated water will leave the back of the boiler in the large inch and a half black iron tubing that heads vertically up and then elbows back to the south wall where all the manifolds and circulation pumps are mounted. There is a separate tempering valve for the first circulation pump (that feeds the porch) because it operates at a higher design temperature of 115°F due to the higher heat loss of the porch caused by the many windows for the small area. The rest of the heat zones of the house are supplied by the black iron manifold to the right with the 4 circulation pumps. This area is all tempered by a different valve that mixes the zones down to a lower design temperature of 90°F.
From each circulation pump copper tubing will go down towards a Uponor flow control manifold that will distribute the properly heated water to the different loops for each zone. Each zone will have a matching manifold for the supply and return. Each return manifold for each zone will then have its outlet head back to the main return for the boiler which will then in turn put the cooler water back under the fire where it can be reheated and again sent out to the house to the proper zone for heat.
You’ll notice there are a few extra outlets on the main return line manifold. One of these is from the heat exchanger within the domestic hot water tank (that uses the 190°F hot water from the boiler to heat the domestic hot water) and the other is for the tempering water to preheat the water before it enters the boiler. Not completely sure if I got this right, but close enough for now.
Anyways, as you can see this is an extremely impressive system that should be very efficient.
There is plenty more to write, but it’s getting late and I’ll wait to really show off all the details once it’s finished. Cross your fingers we get heat tomorrow!