Greetings, Happy Holidays to all...
Did a complete gut and remodel of my kitchen this summer and installed an underfloor hydronic system. Heating contractor did all the piping, from the furnace to the radiant distribution panel, controls, etc. I did the PEX staple up with metal heat transfer plates, and insulated the joist bays with 3.5" fiberglass.
THis is the first winter and I am trying to tune in the system. Until this week, (outdoor temps in the 40's and 50's) the system heated room well. Winter then suddenly arrived in the northeast this week and I can't get much above 65 degrees (internal air temperature), with the outside temp in the high 20's to mid 30's. The flooring manufacturer (wood look laminate) recommends that the "surface" that the flooring is installed on is not above 90 degrees. When job completed in august the contractor set the floor temperature sensor for the radiant system at 90 degrees max. The floor construction is 3/4" red oak (original 125 year old planking), in various places building felt to level the surface, then 1/2" plywood subfloor, unison 2-1 foam underlayment and then the laminate. The sensor is on the bottom of this cross section, mounted in a 4"x4" area where the metal heat transfer surface was removed.
Here is my question. Is there heat transfer loss through the floor cross section of 3/4 oak, 1/2 plywood and foam underlayment, OR does the whole floor eventually reach the same temp, i.e. in this case 90 degrees. The top side of the laminate is nowhere near 90 degrees, but obviously it's radiating the heat upwards. I'm sure you can see where I'm heading...can I nudge the slab sensor limit up a bit? I don't have any way to directly measure the temperature of the topside of the foam underlayment without pulling up the laminate. THANKS for all help.