装 heat pump 应注意的

yangki

发觉大家都只关注在是否合格电工上。。。。 沒电工執照在新西兰从事与电(低放32V的除外)有关的工作已是違法的, 这个我就不多说了.可知 heat pump 的安装不单只是接上电源, 还要接驳铜管, (窗戶式例外) 现在的 heat pump 用的冷媒都是压力较高的R410A, 高压可迏 500psi 以上, 比以往的R22高很多, 使用的铜管也必须适用於R410A的, 接驳方法也異於传统, 管內不能浑有空气, 所以抽真空过程很重要, 一般要低於300~500 micron 以上, 很多为了节省时间把这最重要的工序匆匆帶过, 这也是为什么有些空调使用十年以上也沒问韪, 有些一两年就事故多的原因之一.
还有其他的不太重要的就不多说了 嘻嘻

胖子河豚

Good Luck!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

oceancity

请教:一般要低於300~500 micron 以上, 是在什么范围内呢?

yangki

Here is what the installation guide says to do:
SYSTEM EVACUATION
NOTE: Since the outdoor unit has a refrigerant charge, the gas and liquid line valves must remain closed.
1. Upon completion of leak check, evacuate the refrigerant lines and indoor coil before opening the gas and liquid line valves.
2. Attach appropriate hoses from manifold gauge to gas and
liquid line pressure taps.
NOTE: Unnecessary switching of hoses can be avoided and
complete evacuation of all lines leading to sealed system can be accomplished with manifold center hose and connecting branch hose to a cylinder of HCFC-22 or HFC-410A and vacuum pump.
3. Attach center hose of manifold gauges to vacuum pump.
4. Evacuate until the micron gauge reads no higher than 350 microns.
5. Close off valve to vacuum pump and observe the micron
gauge. If gauge pressure rises above 500 microns in one (1)
minute, then evacuation is incomplete or system has a leak.
6. If vacuum gauge does not rise above 500 microns in one (1)minute, the evacuation should be complete.

When a system has been evacuated below 500 microns, the pump has been shut off and the micron gauge is connected, if the vacuum rises to 1500 microns and stops, there is moisture remaining in the system. If it rises above 1500 microns AND continues to rise, there is a leak. You should allow at least 15 minutes after the pump has been shut off to have this micron gauge reading be accurate. Most of the time when a system will not evacuate below 1500 microns there either is a lot of water or there is a fairly large leak. Regardless, a micron reading taken when the pump is running is useless unless the micron gauge is attached to a totally different part of the system and not connected in any way to the gauges being used to evacuate the system.

If your system would not evacuate below 1530 microns, the installer should have:

1. changed the oil in his vacuum pump, or
2. leak checked the system again (the installation guide states that the system should be leak checked with 350-400 PSIG of nitrogen, but I would bet your installer did not do this), or
3. continued to evacuate until the system reached 350 microns, even if it required several hours.