Gas and Oil Home Heating Furnaces - "adjustable" BTU system

This Q. applies to residential circulated hot-water heating systems------

An "ideal" system would be one where the BTU heat-loss is exactly matched by the BTU "output" of the heating-system.Could this be effected by an out-door electronic temperature- sensor that would moduate either a mixing-valve, or "maintain" the required water-temperature in the furnace.

Is there a "customer market" for such a system?

PATTBAA:

Honeywell makes such a control for commercial hot water systems.
Of the two temp bulbs one senses water temp and the other senses outdoor temp.
It controls boiler water temperature by having the hw temp ride a specific number of degrees above outdoor temp.
One of my customers has this and it works very well.

I'll try to find the mod #.

I know of a lot of large building That work that way now. Only its the guys that work the boilers they set the boiler temp for what the outside temp is. They just know what it has to be to heat the building. Had one had to take it out. Couldnt get it to work right with the out door temp. The sun would get it then the shade got it. then the wall it was on held the cold or heat. Man is still the best.;) ED

I have used Tekmar outdoor reset controls and they work very well. They try to match the water temp to the load and with a little bit of fine tuning, do a good job. You need a supply water sensor, a return water sensor, and an outoor temp sensor.

Look at their web site. http://www.tekmarcontrols.com/about.html

They are not cheap but you couldn't build anything close for less. They are reasonable on repairs too. They are driven by an external 24 vac transformer so if something happens, you can replace that with any 24vac transformer you have.