[BUG] Heating "double" taps after DHW turns on

[mjkl-gh]

Summary of the bug

After DHW is turned on for a short pulse, heating is also turnd on for a short pulse

Steps to reproduce

1. Turn on the DHW for a very short while
2. Hear the Boiler turn on for the hot water, shortly throttling down and immediately back up again to supply the CH with hot water, to immediately shut down again

Note, (I think I have a leak or faulty sensor inside my CH. It's old an I'll replace the entire thing soon. This is pulse happens at random intervals, and is not the "Comfort" setting that keeps the spiral warm. I've turned that off a long time ago.

Expected behavior

1. DHW turns on shortly
2. Nothing else

Actual behavior

As mentioned the Boiler does a start burner cycle, after which it does another. Then shutting audibly violent off.

You can see this happening in the graphs. It's been happening ever since I installed SAT at the beginning of winter. I've just now found the time to report it

Any clue why SAT does a cycle after DHW?

Home Assistant version

2026.3.0

Integration version

4.2.1

Relevant logs

[Alexwijn]

Can you share some logs when this happens? I'm curious of what commands we are sending when this happens.

[mjkl-gh]

Will capture some.

Do you want esphome logs or home assistant component logs?

[mjkl-gh]

I thought I captured something, but I deleted it after becoming sure it was not a double tap, the even was too long and the timing seemed to fit a short pwm cycle better.

[mjkl-gh]

These graphs should show the relevant values sent to esphome during an event

[mjkl-gh]

�[32m2026-04-09 09:12:25.630 INFO (MainThread) [custom_components.sat.climate] Running PWM cycle with state: PWMStatus.OFF�[0m
�[32m2026-04-09 09:12:25.630 INFO (MainThread) [custom_components.sat.coordinator] Set control boiler setpoint to 10°C�[0m
�[32m2026-04-09 09:12:25.630 INFO (MainThread) [custom_components.sat.climate] Control setpoint has been updated to: 10.0°C�[0m
�[32m2026-04-09 09:12:25.631 INFO (MainThread) [custom_components.sat.climate] Heater is already off. No action taken.�[0m
�[32m2026-04-09 09:12:55.631 INFO (MainThread) [custom_components.sat.pwm] Starting new duty cycle (ON state). Current CYCLES count: 1�[0m
�[32m2026-04-09 09:12:55.631 INFO (MainThread) [custom_components.sat.climate] Running PWM cycle with state: PWMStatus.ON�[0m
�[32m2026-04-09 09:12:55.633 INFO (MainThread) [custom_components.sat.coordinator] Set control boiler setpoint to 50°C�[0m
�[32m2026-04-09 09:12:55.633 INFO (MainThread) [custom_components.sat.climate] Control setpoint has been updated to: 50.0°C�[0m
�[32m2026-04-09 09:12:55.634 INFO (MainThread) [custom_components.sat.coordinator] Set central heater state DeviceState.ON�[0m
�[32m2026-04-09 09:13:06.411 INFO (MainThread) [custom_components.sat.pwm] Duty cycle completed. Switching to OFF state.�[0m
�[32m2026-04-09 09:13:06.411 INFO (MainThread) [custom_components.sat.climate] Running PWM cycle with state: PWMStatus.OFF�[0m
�[32m2026-04-09 09:13:06.413 INFO (MainThread) [custom_components.sat.coordinator] Set control boiler setpoint to 10°C�[0m
�[32m2026-04-09 09:13:06.413 INFO (MainThread) [custom_components.sat.climate] Control setpoint has been updated to: 10.0°C�[0m
�[32m2026-04-09 09:13:06.416 INFO (MainThread) [custom_components.sat.coordinator] Set maximum relative modulation to 0%�[0m
�[32m2026-04-09 09:13:06.417 INFO (MainThread) [custom_components.sat.coordinator] Set central heater state DeviceState.OFF�[0m

These are the relevant debug logs during the event. It seems somehow SAT starts a new duty cycle in the ON state immediately after DHW has run