I was thinking of running oxygen barrier PEX under the floor between the joists in a cold room with a crawl space below and then putting rigid foam insulation below to keep the heat in. I have an existing boiler that is used to supply the hot water radiators. Can I hook this system up to my existing boiler?
The systems uses a Weil-McLain gas fueled boiler that circulated the water at 140 degrees F. This boiler used to run 10 large radiators but we remodeled and added an in attic forced air unit and it now only runs 5. The 9 x 15 room already has forced air heat but because it has a crawl space below, three exterior walls, 8 windows, and is located in Minnesota means that that the floor gets very cold in the winter. I thought I could use one of the empty runs to heat the floor of this room and make it more comfortable.
Best Answer
Given that you are now running only half as many radiators, you might be able to "re-purpose" the surplus to provide hot water for your staple up radiant floor heating. An important factor to consider is that maximum floor temperature should never exceed 85 degrees Fahrenheit, so you might need to add a mixing valve and a separate circulator pump. Although, (just thinking out loud) I wonder if you could supply the PEX tubing with "less-hot" water being returned to the boiler. Thereby eliminating the need for a mixing valve and separate circulator pump.