On the fly adjust output clamp

[M-ERiMiEs]

I have air to water heat pump and wish to adjust minimum heating to keep pump operating longer periods for better efficiency. I would use external controller or mayby automation to allow small over heating.

[doff-1]

Just use the min_cycle_duration option, possibly together with the min_off_cycle_duration.
When the heat pump is turned on it should stay on for the minimum duration you set regardles of the temperature.

[M-ERiMiEs]

Thermostat doesnt control heat pump. It runs on fixed outlet water temp and 5 rooms has own thermostats on under floor heating and they control valves on the heating circuits.

For longer periors I mean it runs 24/7 on minumum load as it takes like 15-20min to heat up at -15C.

[doff-1]

I'm not sure you're asking in the right place for what you want to achieve?
Now you're saying you can't use the thermostat settings because they control room temperature, and you want the water heater to continue running.

By your description the heatpump controls itself based on water outlet temperature, independent of any room thermostats.
so ether you manipulate the heatpumps temperature sensor or send the heatpump some kind of override signal? Another option is to increase the heating in your rooms to cool down the water making the heatpump run to warm it again.
If you run it like this you shold also implement some kind of safeguard to prevent the water geting warmer than the system can handle.

Do you have any control over the heatpump today? or only room thermostats?
Do you have any way to tell if the heatpump is running or not?

[M-ERiMiEs]

This is right as I want to manipulate output clamp to keep enought heating to rooms. Yes it does some over heating to the rooms but I dont mind it if I can save energy with it. When thermostats pwm duty goes to small heat pump starts on/off cycling and it consumes excess energy to heat it up in every cycle.

Heat pump is connected to HA also so I can see its current load etc and make automations based on this and control outlet temps etc but it has min load what it runs like 2-3kw of heat altought heat pump is inverted controlled and its outlet temps etc are fine and working good.

[doff-1]

My immediate thought is that the best way to solve your issue is an automation that increases the set temperature on one or more thermostats when your heatpump load reaches a defined lower current load. You could then have another trigger at a higher load that reverts your thermostats setpoint to your actual desired value.
This way you extract more heat from the water when the heatpump is close to turning off. Deicing might make all this more difficult.

[M-ERiMiEs]

Yes I might work also but I want still keep minimal heating for comfort.

[doff-1]

Just don't turn down the thermostats then.