Feature request: Runtime control of output clamp for floor comfort

[Icetuborg]

Feature request: Runtime control of output clamp for floor comfort

Hi,

I am using HASmartThermostat for hydronic underfloor heating, and I would like to ask if there is already a recommended way to achieve the following.

I want the thermostat to keep regulating normally with PID, but sometimes I want to enforce a small minimum output to keep the floor comfortable.

For example:

Normal mode:
PID output allowed: 0-100 %

Comfort mode:
PID output allowed: 15-100 %

The goal is not to increase the room temperature setpoint.

The goal is only to prevent the PID output from going completely to 0% when comfort mode is enabled.

This is useful for heavy concrete underfloor heating, where the room temperature may already be correct, but the floor can become unpleasantly cold if heating is completely stopped for a long time.

Current configuration

HASmartThermostat already supports:

out_clamp_low: 15
out_clamp_high: 100

But as far as I can see, these values are configured statically.

What I would like is to change them dynamically while Home Assistant is running.

Example of the desired function

Enable a minimum comfort output:

action: smart_thermostat.set_output_clamp
target:
  entity_id: climate.bathroom
data:
  clamp_low: 15

Disable the minimum comfort output again:

action: smart_thermostat.set_output_clamp
target:
  entity_id: climate.bathroom
data:
  clamp_low: 0

Optionally, both limits could be supported:

action: smart_thermostat.set_output_clamp
target:
  entity_id: climate.bathroom
data:
  clamp_low: 15
  clamp_high: 100

My Home Assistant use case

I use two helpers:

input_boolean.bathroom_comfort
input_number.bathroom_comfort_minimum

The number helper controls the desired minimum output, for example from 0% to 30%.

The intended behaviour is:

Comfort OFF:
clamp_low = 0

Comfort ON:
clamp_low = value of the comfort minimum slider

For example, if the comfort minimum slider is set to 15%:

PID calculates 8%  -> actual minimum output becomes 15%
PID calculates 25% -> actual output remains 25%
PID calculates 60% -> actual output remains 60%

So the PID controller is still responsible for regulating the heating.

The comfort function only changes the minimum allowed output.

Why I would like this

This keeps three different functions separate:

1. Room temperature setpoint
2. PID regulation
3. Minimum floor comfort heating

This means I do not need to artificially increase the room temperature setpoint just to keep the floor slightly warm.

It is especially useful with slow hydronic underfloor heating in heavy concrete floors.

Question

Before requesting a software change:

Is there already another recommended way to achieve this in HASmartThermostat?

If there is already a supported method, I would prefer to use that instead of modifying the integration.

If not, would you consider adding a runtime service for changing out_clamp_low and possibly out_clamp_high?

I have already tested this locally by adding a runtime output-clamp service to climate.py, and it works very well for this use case.

If useful, I can also provide the exact code changes I am currently testing.

Thanks for maintaining HASmartThermostat.

[ScratMan]

Hello,

Adding a service to control additional parameters would require to add them to climate's state, store them in DB and restore it at start.
I'd rather propose to accept either a static float value or a unique_id from a float entity for out_clamp_low and out_clamp_high parameters.
If the integration detects a unique_id, it will ask HA for the value, fallback to output_min/output_max if invalid (unknown, unavailable, not a number, low > high or not in min/max range) and use it to clamp the control_output from the PID.

You could then use an automation to set the clamping value entities directly.
Would it fit your requirements ?

[Icetuborg]

Hello, Yes, that would fit my requirements very well, and I actually prefer this approach over adding another service. My use case is: * out_clamp_low = 0 when comfort heating is disabled * out_clamp_low = 15 (or another user-selected value) when comfort heating is enabled I already use an input_number helper in Home Assistant for the comfort minimum, so being able to reference that entity directly from out_clamp_low would be a very clean solution. For example: out_clamp_low: input_number.stort_badevaerelse_komfort_minimum out_clamp_high: 100 Then Home Assistant automations can simply change the helper value between 0 and the desired comfort minimum. This would also remove the need for my current local modification of climate.py. One question: Would the integration update the clamp value immediately when the referenced number entity changes state, or would it only read the value on the next PID/control calculation? Either way, this sounds like a very good solution for my use case. Thanks for considering it. /Dennis Sendt fra min iPhone Den 15. okt. 2026 kl. 15.52 skrev Adrien Bonnat ***@***.***>:  Hello, Adding a service to control additional parameters would require to add them to climate's state, store them in DB and restore it at start. I'd rather propose to accept either a static float value or a unique_id from a float entity for out_clamp_low and out_clamp_high parameters. If the integration detects a unique_id, it will ask HA for the value, fallback to output_min/output_max if invalid (unknown, unavailable, not a number, low > high or not in min/max range) and use it to clamp the control_output from the PID. You could then use an automation to set the clamping value entities directly. Would it fit your requirements ? — Reply to this email directly, view it on GitHub<#323?email_source=notifications&email_token=BUNL7XVADST6LUHJYBBW5XT5UDJBLA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBZGUYDIOBWUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVRTG633UMVZF6Y3MNFRWW#discussioncomment-18950486>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/BUNL7XQ5MKXWXBJMNJ3HQIL5UDJBLAVCNFSNUABIKJSXA33TNF2G64TZHM2DCNZUGAYDAMRYHNCGS43DOVZXG2LPNY5TCMJQGA4TGNRZUF3AE>. Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS<https://github.com/notifications/mobile/ios/BUNL7XUCH3TFEPSMXGW4ISD5UDJBLA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBZGUYDIOBWUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVJTG633UMVZF62LPOM> and Android<https://github.com/notifications/mobile/android/BUNL7XRZNSEGT3EFBCXB4LD5UDJBLA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBZGUYDIOBWUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVZTG633UMVZF6YLOMRZG62LE>. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.***>

[ScratMan]

I'm considering adding a listener on the clamp value entity to trigger a heater level update (no need to update the PID value in my opinion, just reapply it with clamp).

I'll work on that after merging the config flow PR. It will need testing as it will require to manage heat and cool modes, with control values being positive or negative.

[Icetuborg]

That sounds ideal for my use case. A listener on the clamp value entity that reapplies the current control output with the new clamp should be perfectly sufficient. I agree that recalculating the PID itself should not be necessary. My main requirement is simply that a change to the referenced clamp entity takes effect promptly, so this approach sounds very good. I’ll be happy to test it with my hydronic underfloor heating setup once it is available. Thanks for looking into it. Sendt fra min iPhone Den 15. okt. 2026 kl. 19.37 skrev Adrien Bonnat ***@***.***>: I'm considering adding a listener on the clamp value entity to trigger a heater level update (no need to update the PID value in my opinion, just reapply it with clamp). I'll work on that after merging the config flow PR. It will need testing as it will require to manage heat and cool modes, with control values being positive or negative.

[ScratMan]

Please test with 2026.10.2-beta4