slab-sim

Conventional thermostat vs weather-compensated control

Same house, same week of Bariloche weather, same gas boiler. One is controlled by a conventional on/off room thermostat; the other by continuous circulation with a weather-compensated supply temperature. Watch the indoor temperature. New here? How it works →

Big diurnal swing, heavy solar gain. The hardest case — it most exposes the on/off controller's overshoot.

Conventional — gas
0.0 kWh
Weather-comp — gas
0.0 kWh
Difference
+0.0 %

Indoor air temperature

comfort band shaded (setpoint ± 0.5 °C)

Supply water temperature

smooth curve vs 45 °C on/off square wave
d0 00:00

Conventional on/off

Weather-compensated

This is a calibrated physical model, not a measurement. It uses an RC thermal model of a 120 m² slab house and a non-condensing gas boiler with real modulation, cycling and mixing-valve limits. Actual results depend on your building's insulation, slab, glazing and boiler. The intent is to show the control paradigm difference — an on/off thermostat cannot settle a high-mass slab — not to promise a specific number for a specific house.