75gmck25
Well-known member
Not a garage question, but I know there are some knowlegeable folks here.
I have a gas boiler and cast iron radiator heat in my 1250 sq ft house, and it works well. We are building out a new porch that will add about 300 sq ft of heated area, and to save floor space I would like to use hydronic heat in the floors instead of radiators. Since this is new contruction, my plan to use a product like this one when they frame the and install floor underlayment (this underlayment is thicker than standard OSB or plywood). https://www.warmboard.com/warmboard-s .
The problem I need to solve is that my current system runs at 140 degrees max and is set to 100 degrees minimum. In most cases its more like 135 degrees when heat is going, and it typically drops by about 20 degrees in the return lines. However, in-floor heat needs more like 90-100 degrees, so I will need to zone the system and drop the temps for the new area.
There are zone valves that can recirculate cooler water to drop the temps, but in a closed system I don't know how well they work. I assume you would have to cut off hot water flow to the low temp zone when you hit the set temp (e.g., 100 degrees), and recirculate the water in that lower temp zone until it drops and you need more heat. However, since I only have one thermostat, it seems I may have a problem with temperature imbalance between the high and low temp zones. Maybe I need two thermostats?
Anyone have experience/suggestions about getting a dual temp zone hydronic system to work? I'm in the DC/Northern VA area, where hydronic heat is no longer used very often, so it may be difficult to find a dealer with experience in a dual temp system.
Thanks,
Bruce
I have a gas boiler and cast iron radiator heat in my 1250 sq ft house, and it works well. We are building out a new porch that will add about 300 sq ft of heated area, and to save floor space I would like to use hydronic heat in the floors instead of radiators. Since this is new contruction, my plan to use a product like this one when they frame the and install floor underlayment (this underlayment is thicker than standard OSB or plywood). https://www.warmboard.com/warmboard-s .
The problem I need to solve is that my current system runs at 140 degrees max and is set to 100 degrees minimum. In most cases its more like 135 degrees when heat is going, and it typically drops by about 20 degrees in the return lines. However, in-floor heat needs more like 90-100 degrees, so I will need to zone the system and drop the temps for the new area.
There are zone valves that can recirculate cooler water to drop the temps, but in a closed system I don't know how well they work. I assume you would have to cut off hot water flow to the low temp zone when you hit the set temp (e.g., 100 degrees), and recirculate the water in that lower temp zone until it drops and you need more heat. However, since I only have one thermostat, it seems I may have a problem with temperature imbalance between the high and low temp zones. Maybe I need two thermostats?
Anyone have experience/suggestions about getting a dual temp zone hydronic system to work? I'm in the DC/Northern VA area, where hydronic heat is no longer used very often, so it may be difficult to find a dealer with experience in a dual temp system.
Thanks,
Bruce