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TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)

TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)

TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)
TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)
Tuesday
Tags: #Installation
Model: KE100 KIT  
Hardware Version:
Firmware Version:

I’m having an issue with my TP-Link Kasa KE100 radiator thermostats.

 

They don’t fully close the valve – there is always a slight flow of hot water, even when the thermostat is set to off. The radiator stays slightly warm.

 

What’s strange is that if I install a manual thermostat on the same valve, it closes completely with no flow at all. So the valve itself seems to be working fine.

 

I’ve already tried using a spacer to increase the pressure on the valve pin, but it didn’t solve the problem.

 

It seems like the KE100 doesn’t push the valve pin far enough or doesn’t apply enough force to fully close it.

 

Has anyone experienced something similar or found a solution?

 

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#1
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5 Reply
Re:TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)
Wednesday

  @Timo_ 

 

KE100 enters frost protection mode when turned off, helping protect the pipes from freezing. If you need to close the valve completely, enable Summer Mode and select Fully Closed.

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#2
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Re:TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)
Thursday

  @Wayne-TP 

 

Thank you for your reply, that would help if I were turning the system off manually. However, I’m using an automation with a window sensor, and two of the valves don’t close when they’re supposed to. So I’m looking for a solution to that behavior, not for manual control.

 

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#3
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Re:TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)
Friday

  @Timo_ 

 

If you need to close the valve completely, you’ll have to switch to Summer Mode. Your usage is a bit unusual, have you considered the risk of pipes freezing or cracking if the valve is fully shut off in low temperatures?  Additionally, I should point out that reheating the system after a full shutdown would consume significantly more energy.

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#4
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Re:TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)
Friday

  @Wayne-TP 

That’s actually not unusual at all. In Germany, it’s standard practice to turn off the heating when a window is open – you ventilate briefly and then close it again.

 

The real issue here is different: one of the radiators still gets very warm even though the valve should be fully closed. That suggests the valve isn’t closing properly rather than a problem with how the system is being used.

 

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#5
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Re:TP-Link Kasa KE100 doesn’t fully shut off radiator (constant slight flow)
an hour ago

  @Timo_ 

 

The frost protection mode operates at a relatively low temperature, the default minimum is set to 5°C (unless changed — you can verify here: KE100 Device Settings > Frost Protection), so it won't affect ventilation that much.

 

It's understandable that usage habits vary from person to person. I’ll document your feedback and share it with the relevant team for evaluation.

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#6
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