1. The temperature control system of the fresh air unit is composed of a proportional integral temperature controller, a temperature sensor installed in the air supply duct and an electric control valve. The function of the controller is to transmit the air supply temperature detected by the temperature sensor in the air supply duct to the temperature controller for comparison with the temperature set by the controller, and according to the results of PI calculation, the temperature controller sends an open/close valve signal to the electric control valve, so as to keep the air supply temperature within the required range.

2、電動(dòng)調(diào)節(jié)閥與風(fēng)機(jī)連鎖，以保證切斷風(fēng)機(jī)電源時(shí)風(fēng)閥亦同時(shí)關(guān)閉。電動(dòng)調(diào)節(jié)閥亦可實(shí)現(xiàn)與風(fēng)機(jī)的聯(lián)動(dòng) ，當(dāng)風(fēng)機(jī)切斷電源時(shí)關(guān)閉電動(dòng)調(diào)節(jié)閥。 兩種連鎖線路連接方式，分別用于斷電復(fù)位設(shè)備和電關(guān)設(shè)備，用戶可據(jù)具體情況自行取舍。（有防凍要求的場合可通過行程限位器將熱水閥位保持在要求的開度）。

2. The electric control valve is interlocked with the fan to ensure that the air valve is also closed when the fan power is cut off. The electric control valve can also realize linkage with the fan. When the fan is cut off, close the electric control valve. Two interlocking line connection modes are used for power-off reset equipment and power-off equipment, and users can choose between them according to specific conditions. (In case of antifreeze requirements, the hot water valve can be kept at the required opening through the travel limiter).

3、在需要制冷時(shí)，溫控器置于制冷模式，當(dāng)傳感器測量的溫度達(dá)到或低于設(shè)定溫度時(shí)，溫控器給電動(dòng)閥一個(gè)關(guān)閥信號(hào)，電動(dòng)閥的關(guān)閥接點(diǎn)接通閥門關(guān)閉。如果測量溫度沒達(dá)到設(shè)定溫度，溫控器給電動(dòng)閥一個(gè)開閥信號(hào)，電動(dòng)閥開閥接點(diǎn)接通閥門打開。

3. When refrigeration is required, the temperature controller is placed in the refrigeration mode. When the temperature measured by the sensor reaches or is lower than the set temperature, the temperature controller sends a valve closing signal to the electric valve, and the valve closing contact of the electric valve is connected to the valve and closed. If the measured temperature does not reach the set temperature, the temperature controller will send an opening signal to the electric valve, and the valve opening contact of the electric valve will be connected to open the valve.

4、在需要制熱時(shí)，溫控器置于制熱模式，當(dāng)傳感器測量的溫度達(dá)到或高于設(shè)定溫度時(shí)，溫控器給電動(dòng)閥一個(gè)關(guān)閥信號(hào)，電動(dòng)閥的關(guān)閥接點(diǎn)接通閥門關(guān)閉。如果測量溫度沒達(dá)到設(shè)定溫度，溫控器給電動(dòng)閥一個(gè)開閥信號(hào)，電動(dòng)閥開閥接點(diǎn)接通閥門打開。

4. When heating is required, the temperature controller is placed in the heating mode. When the temperature measured by the sensor reaches or exceeds the set temperature, the temperature controller sends a valve closing signal to the electric valve, and the valve closing contact of the electric valve is connected and the valve is closed. If the measured temperature does not reach the set temperature, the temperature controller will send an opening signal to the electric valve, and the valve opening contact of the electric valve will be connected to open the valve.

5、當(dāng)過濾網(wǎng)堵塞時(shí)或當(dāng)其超過規(guī)定值時(shí)，壓差開關(guān)給出的開關(guān)信號(hào)。當(dāng)盤管溫度過低時(shí)，低溫防凍開關(guān)給出開關(guān)信號(hào)，風(fēng)機(jī)停止運(yùn)行，防止盤管凍裂。

5. When the filter screen is blocked or exceeds the specified value, the switch signal given by the differential pressure switch. When the temperature of the coil is too low, the low temperature antifreeze switch gives the switch signal, and the fan stops running to prevent the coil from freezing.