When installing a radiant floor heating system stay away from small area zones (a bathroom for example). Because of the high efficiency condensing boilers most radiant systems uses will cycle on and off frequently when converted to small thermostatically controlled zones. On and off frequent operation eventually can lead to boiler component failure.
Avoid Small Zones with Radiant Heat
It is not advisable to zone small areas of a house. The condensing, modulating boilers typically used in radiant floor heating systems typically do not modulate below 20 – 25,000 BTU. When small heat loss areas are zoned this causes frequent on – off boiler operation leading to component failures.
Small Area Radiant Floor Heat
It is not advisable to zone small areas of a house. The condensing, modulating boilers typically used in radiant floor heating systems typically do not modulate below 20 – 25,000 BTU. When small heat loss areas are zoned this causes frequent on – off boiler operation leading to component failures.
Although it is not advisable to incorporate small areas for radiant heating zoning (thermostatic controlled). It can be done by installing a “buffer tank” into the system. A buffer tank is a small (20 gallon) tank tied into T6 boiler piping that will store hot system water to prevent boiler from short cycling.
Zoning of Radiant Heat
Zoning or separate thermostatic control of area can be easily accomplished with radiant floor heating. Typically the areas within concrete radiant are zoned. The bedroom zoned areas are zoned, the living areas on a zone. Other areas usually zoned area garage, workshop, etc.
Condensing Boilers
We find ourselves centering in on the heart of the Radiant Heating System for my first ever heating blog. This heart, is of course the heating source, or boiler. The thing that converts fuel energy into real usable heating energy! That is…….that thing in the basement that keeps us comfy when is freezing outside.
With so many types of “condensing: boilers” inhabiting the marketplace, I figured this particular blog will focus on just one. Low mass condensing boilers can be floor mounted, more typically hung on a wall. These “wall hung” boilers are really gaining in popularity these days, due in part to the fact that they can be installed just about anywhere in the building. That thing in the basement can now be located on any floor of the structure!
The term condensing comes from the way the fuel is utilized in the combustion chamber. A non-condensing boiler wastes fuel in the form of very hot flue gases, and wuther around down near the 80% to 87% efficiency range. Condensing boilers’ are designed to operate in the 88% to 98% A.F.U.E range(annual fuel utilization efficiency). A.F.U.E. is the accepted platform by which all boilers are tested to ensure a level playing field. This rating is posted on the unit itself and on the “energystar.gov” website by manufacturer and model.
Condensing boilers turn so much of the fuel source into usable energy that flue gases leaving the unit have been cooled below the dew point of the flue gas mixture. This means that the water in those flue gases is parting ways and finding its own way out of the boiler via gravity, this condensate is quite acidic. All condensing boiler must be constructed of material that can stand up to the added stress the acidic condensate, as well as providing a path for the water to exit the unit to a drain.
Please tune in next month for the next installment of “condensing boilers” in Matts heating blog. We will look at the finer points and not so fine points of “wall hung” boilers. See you there!
