Adjusting both curve and offset at the same time
The problem
When you change both parameters at the same time, you don't know which change had the effect. If the result is wrong, you have to guess which change was the issue.
The solution
Always make one change at a time. Wait at least 24 hours and evaluate before making the next adjustment.
Making too large changes
The problem
Changing the curve from 3 to 6 or the offset by 5 degrees gives unpredictable results. You often overshoot the optimum and then have to adjust back.
The solution
Adjust by a maximum of 0.5-1 steps on the curve or 1-2 degrees on the offset per round. Small steps give you control.
Not waiting for thermal inertia
The problem
The house and heating system have thermal mass. When you change the curve, it takes hours – sometimes a full day – before the full effect is reached. If you change too quickly, you never see the true result.
The solution
Wait at least 24 hours between each change. With underfloor heating in concrete, it can take even longer.
Closing thermostats during calibration
The problem
If thermostats are throttled during calibration, the true effect of the heating curve is hidden. You end up with a curve that provides too little heat when the thermostats are later opened.
The solution
Set all thermostats to maximum during calibration. When the curve is correct, the thermostats should be able to stay open without it getting too warm.
Relying on thermostats instead of the curve
The problem
Compensating for an incorrect curve by adjusting thermostats in every room is inefficient. The system produces water that's too hot and the thermostats throttle – energy is wasted.
The solution
Adjust the curve so that the thermostats can stay nearly fully open. Use thermostats only for fine-tuning between rooms, not as the primary control.
Ignoring different heating zones
The problem
If the house has both underfloor heating and radiators on the same circuit, one curve can't suit both. Underfloor heating requires a lower temperature than radiators.
The solution
If possible, use separate circuits with a mixing valve group for different systems. Otherwise, compromise with a middle curve and use thermostats for fine-tuning.
Forgetting night setback and scheduling
The problem
An active night setback can give the impression that the curve is wrong. The temperature drops at night and the house doesn't warm up in time for morning – even though it's actually the scheduling that's causing the problem.
The solution
Turn off scheduling and night setback during calibration. Re-enable them only once the base curve is correct.
Summary
How to avoid the mistakes:
- One change at a time
- Small steps (max 0.5-1 on the curve, 1-2° on the offset)
- Wait at least 24 hours between changes
- Thermostats at maximum during calibration
- Adjust the curve – not the thermostats
- Consider different heating zones
- Turn off scheduling during calibration