Vitodens, Reset & Warm-Weather Shutdown Part 2

Mike T., Swampeast MO

Did something strange.

Used the temperature I measure on the supply pipe to establish a new curve. Used measured temp at outside design and in the mid-50s adding 3° (guess for difference between water in pipe and surface I can measure).

Curve came out to 1.0 ratio with 0° shift. e.g. 69° supply at 67° outside with 68° room temp setting; 81° supply at 55° outside with 68° room temp setting.

Set this way for about 4 hours with outside temp in the mid-50s and cloudy/rainy.

Boiler continues to "pulse" with supply, return and flue temps all in a gradual decline. Return temp seems to have leveled off at about 73°. Supply seems to be leveling off with average at about 78° with setpoint of 81°.

Space temp throughout the house mainly stable. Cranked the TRV in my office. Heard flow increase, but the rad really didn't get any hotter after half an hour.

Mike T., Swampeast MO

Not surprisingly, the radiant bath floors have gone stone cold and their air temp is falling as well.

Rest of the spaces continue to maintain TRV setpoint. It's coolish and damp outside and I feel an unaccustomed "chill" in the house that seems to be growing.

Boiler still "pulsing" with the same frequency with each pulse consuming the same amount of gas.

Stange...

Mark Eatherton1

Velkome to...

Eurocave conditions. The German way is "If you're chilled, put on a sveater und keep your finkers AUF of the thoimastat."

That is tough for Americans to get used to...

ME

Mike T., Swampeast MO

Wore a sweater this morning. Usually switch to shirt sleeves this time of year.

Space temp maintained itself during the night. Outside temp had dropped to 47° and the boiler continued to pulse. With the old curve, it would start putting out bursts (burns of 1-2 hours) by that temp.

Went back to my old curve--not too impressed with the "Eurocave". Besides--even if I did turn up the heat via the "thoimastats", it wouldn't have done anything...