https://github.com/Koenkk/zigbee2mqtt/issues/21647

ext.js

const fz = require('zigbee-herdsman-converters/converters/fromZigbee');
const tz = require('zigbee-herdsman-converters/converters/toZigbee');
const exposes = require('zigbee-herdsman-converters/lib/exposes');
const reporting = require('zigbee-herdsman-converters/lib/reporting');
const tuya = require('zigbee-herdsman-converters/lib/tuya');
const e = exposes.presets;
const ea = exposes.access;
const legacy = require('zigbee-herdsman-converters/lib/legacy');
const utils = require('zigbee-herdsman-converters/lib/utils');
const { Buffer } = require('node:buffer');


const definition = {
    fingerprint: tuya.fingerprint('TS0601', ['_TZE204_dzuqwsyg']),
    model: 'TYBAC-006',
    vendor: 'Tuya',
    description: 'Wall-mount thermostat for 2-pipe fan-coil unit',
    fromZigbee: [tuya.fz.datapoints],
    toZigbee: [tuya.tz.datapoints],
    onEvent: tuya.onEventSetLocalTime,
    configure: tuya.configureMagicPacket,
    exposes: [
        e.binary('state', ea.STATE_SET, 'ON', 'OFF').withDescription('Turn the thermostat ON/OFF'),
        e.child_lock(),
        e.climate()
            .withLocalTemperature(ea.STATE)
            .withSetpoint('current_heating_setpoint', 5, 35, 1, ea.STATE_SET)
            .withSystemMode(['cool', 'heat', 'fan_only'], ea.STATE_SET)
            .withFanMode(['low', 'medium', 'high', 'auto'], ea.STATE_SET)
            .withLocalTemperatureCalibration(-5, 5, 0.5, ea.STATE_SET),
        e.min_temperature().withValueMin(5).withValueMax(15),
        e.max_temperature().withValueMin(15).withValueMax(45),
        e.binary('eco_mode', ea.STATE_SET, 'ON', 'OFF').withDescription('ECO mode ON/OFF'),
        e.max_temperature_limit().withDescription('ECO Heating energy-saving temperature (default: 20 ºC)').withValueMin(15).withValueMax(30),
        e.min_temperature_limit().withDescription('ECO Cooling energy-saving temperature (default: 26 ºC)').withValueMin(15).withValueMax(30),
        e.deadzone_temperature().withValueMin(0).withValueMax(5).withValueStep(1),
        e.binary('valve', ea.STATE, 'OPEN', 'CLOSE').withDescription('3-Way Valve State'),
        e.binary('manual_mode', ea.STATE_SET, 'ON', 'OFF').withDescription('Manual = ON or Schedule = OFF'),
        ...tuya.exposes.scheduleAllDays(ea.STATE_SET, 'HH:MM/C HH:MM/C HH:MM/C HH:MM/C HH:MM/C HH:MM/C'),
    ],
    meta: {
        tuyaDatapoints:
        [
            [1, 'state', tuya.valueConverter.onOff],
            [null, 'system_mode', {
                // Extend system_mode to support 'off' in addition to 'cool', 'heat' and 'fan_only'
                to: async (v, meta) => {
                    const entity = meta.device.endpoints[0];

                    // Power State
                    await tuya.sendDataPointBool(entity, 1, v !== 'off', 'dataRequest', 1);

                    switch (v) {
                    case 'cool':
                        await tuya.sendDataPointEnum(entity, 2, 0, 'dataRequest', 1);
                        break;
                    case 'heat':
                        await tuya.sendDataPointEnum(entity, 2, 1, 'dataRequest', 1);
                        break;
                    case 'fan_only':
                        await tuya.sendDataPointEnum(entity, 2, 2, 'dataRequest', 1);
                        break;
                    }
                },
            }],
            [2, null, {
                // Map system_mode back to both 'state' and 'system_mode'
                from: (v, meta) => {
                    const modes = ['cool', 'heat', 'fan_only'];

                    return {
                        system_mode: modes[v],
                        system_mode_device: modes[v],
                    };
                },
            }],
            [4, 'eco_mode', tuya.valueConverter.onOff],
            [16, 'current_heating_setpoint', tuya.valueConverter.divideBy10],
            [19, 'max_temperature', tuya.valueConverter.divideBy10],
            [24, 'local_temperature', tuya.valueConverter.divideBy10],
            [26, 'min_temperature', tuya.valueConverter.divideBy10],
            [27, 'local_temperature_calibration', tuya.valueConverter.localTemperatureCalibration],
            [28, 'fan_mode', tuya.valueConverterBasic.lookup(
                {'low': tuya.enum(0), 'medium': tuya.enum(1), 'high': tuya.enum(2), 'auto': tuya.enum(3)})],
            [36, 'valve', tuya.valueConverterBasic.lookup({'OPEN': 0, 'CLOSE': 1})],
            [40, 'child_lock', tuya.valueConverter.lockUnlock],
            [103, 'deadzone_temperature', tuya.valueConverter.raw],
            [104, 'min_temperature_limit', tuya.valueConverter.divideBy10],
            [105, 'max_temperature_limit', tuya.valueConverter.divideBy10],
            [106, 'schedule_sunday', tuya.valueConverter.thermostatScheduleDayMultiDPWithDayNumber(7)],
            [107, 'schedule_saturday', tuya.valueConverter.thermostatScheduleDayMultiDPWithDayNumber(6)],
            [108, 'schedule_friday', tuya.valueConverter.thermostatScheduleDayMultiDPWithDayNumber(5)],
            [109, 'schedule_thursday', tuya.valueConverter.thermostatScheduleDayMultiDPWithDayNumber(4)],
            [110, 'schedule_wednesday', tuya.valueConverter.thermostatScheduleDayMultiDPWithDayNumber(3)],
            [111, 'schedule_tuesday', tuya.valueConverter.thermostatScheduleDayMultiDPWithDayNumber(2)],
            [112, 'schedule_monday', tuya.valueConverter.thermostatScheduleDayMultiDPWithDayNumber(1)],
            [101, 'manual_mode', tuya.valueConverter.onOff],
        ],
    },
};

module.exports = definition;