Sonoff TRVZB: OnOff cluster commands timeout despite successful execution

[jaapp]

Device Information

• Manufacturer: SONOFF | Model: TRVZB | Firmware: 0x00001401
• Integration: ZHA

Problem

OnOff cluster commands (switch.turn_on/turn_off) timeout with error:

Failed to send request: device did not respond

Yet the device works:

• ✅ Command executes (state changes correctly)
• ✅ Device sends attribute reports confirming state
• ✅ Subsequent commands work normally
• ❌ API returns 500 error

Impact: Only affects switch entity. Climate entity (climate.set_hvac_mode) works perfectly.

Root Cause

Device violates ZCL spec on OnOff cluster (0x0006):

• Receives command with disable_default_response=0 (expects response)
• Executes command successfully
• Sends attribute report with wrong TSN instead of command response
• ZHA times out waiting for correct response

Evidence

Command sent (TSN=31):

[zigpy.zcl] [0x7A92:1:0x0006] Sending request header: ZCLHeader(
    disable_default_response=0, tsn=31, command_id=0
)

Device response (~1.3s later):

[zigpy.zcl] [0x7A92:1:0x0006] Received command 0x0A (TSN 14): Report_Attributes(...)
[zigpy.zcl] [0x7A92:1:0x0006] Attribute report received: on_off=<Bool.false: 0>

Issue: Response TSN=14 ≠ Command TSN=31. Attribute report, not command response.

How Zigbee2MQTT Avoids This

Z2M doesn't expose switch entity—only climate entity using system_mode:

{"system_mode": "off"}   // Instead of switch.turn_off
{"system_mode": "heat"}  // Instead of switch.turn_on

Works because Thermostat cluster uses attribute writes (not commands). No timeout issues reported.

Reference: Z2M TRVZB Docs

Proposed Solutions

Option 1: Fix with Quirk

Add quirk using disable_default_response=True:

Pros: Maintains multi-entity approach, backward compatible
Cons: More complex, relies on non-standard behavior

Option 2: Hide Switch Entity (Like Z2M)

Don't expose OnOff cluster in ZHA device configuration.

Pros: Simple, proven, no quirk needed
Cons: Breaking change, less flexible

Workaround

Use climate entity instead of switch.

Device Signature

Endpoint 1 (Profile 0x0104, DevType 0x0301):
  Input: 0x0000 (Basic), 0x0001 (Power), 0x0006 (OnOff ←), 0x0201 (Thermostat)

[Hedda]

@elupus could this be related or similar to #591 ?

[elupus]

Could be. But the code hard to grasp due to using cluster handlers being hydras on both side.

[puddly]

@jaapp can you attach diagnostic JSON for the device and a debug log of you sending this command? One minute of context should be enough.