To vacuum your ac system without a pump, you have to keep the pipes in the correct configuration. Then you must keep the required valves open and closed respectively. Finally, you can evacuate your ac system.
How to Vacuum the AC System Without a Pump
A few key factors need to be kept in mind. The discharge pipe should be connected to the outdoor unit. The suction pipe should be kept open. Another important thing is that the discharge L key valve should be kept open. And you should also see that the suction L key valve should be closed. This is common for home units.
After the above-stated things are done the outdoor unit should be started. This will enable air to leave the discharge pipe. The air will come out from the suction pipe. After this, we need to wait for 5-7 minutes. Then the suction pipe can be connected. The outdoor unit must be turned off after this. Then you can charge the system.
Vacuuming for compressor replacement is a bit different. You need to follow the following stated steps.
Step-1: Turn off the compressor and change the pressure
Turn of compressor
After installation, turn off the compressor. Mark out the high side. Eventually, this side will have an access valve. Press it down. Pressure should be monitored on the other terminal that homes the low side. After the pressure reaches its lowest value the access valve should be closed.
Change the pressure
This process generally takes about five minutes. After this, the low side should be charged to around 14 psi. Then wait approximately 3 minutes so that the pressures may equalize. Now the compressor should be turned on and the access valve on the high side should be depressed.
Step-2: Close the appropriate valves
After the pressure on the low side goes as low as possible the high side access valve should be closed. After this, the compressor should be turned off.
Finally, the compressor should be turned on and the access valve on the right side should be depressed. After the pressure on the low side reaches its lowest value the high side access valve should be closed and the compressor should be turned off.
Step-3: Repeat and check
You’ll need to repeat the previously stated steps 2, 3, and 4. You’ll need to see that on successful evacuations the pressure on the low side will not go as low. The reason for this is the absorption of refrigerant as well as the compressor oil and subsequent slow release.
Step-4: Equalize and finalize
Wait for the pressure to equalize
Then charge the low side of the system to around 14 psi. After this, you must delay for about three minutes. In the meantime, the pressure will gradually get identical. Then it’s time to press the access valve. You’ll find that on the high side. But before that, don’t forget to turn the compressor on. The valve is subsequently closed and the air is purged from the system.
Last of all charge the system with the required amount of refrigerant. Then you might turn on the compressor. This will conclude your steps. But you may need to adjust some minute things if necessary.
The procedure stated above holds for vacuuming your car ac system also. You just need to make some adjustments to get the proper vacuuming action. But the core steps remain the same.
DIY Vacuum Pump
The compressor for any refrigerator can be easily transformed into a DIY pump. You can take the following steps to build one yourself.
Step-1: Gather the Components
First, you need a fridge compressor. You can get one easily from any fridge repair shop. Then you need the required components and tools.
- A power Switch with the faceplate
- Junction Box
- A cord with a plug
- Tennis ball and some scraps of rag
- Copper tubing
- A vacuum gauge
- Tubes made of plastic
- Compressor Oil
- Soldering torch
- Small pipe cutter
- Screw Driver
- Hot Glue gun
- Large syringe
Step-2: Perform a Maintenance Check
Then you must look towards maintenance. Clean all the pieces properly. There are three tubes in the compressor. They are in, out, and process. In and out are for air and process is for oil.
Step-3: Put the Pieces Together
Install the pipes
All the pipes and tubing must be installed properly. Use the glue guns to install the plastic pipes. You can use the soldering torch for the metal components. Before installing the tennis ball, you need to make a few modifications. Just puncture a few holes and insert scarps of rags.
It serves double duty as not only an oil vapor collector but also a muffler. On the inline pipe, you need to straighten the pipe so it runs horizontally. You need to cut the squeezed end off with a pipe cutter. Take a piece of ¼ I.D plastic and hot glue it to the pipe. You can easily cut it off later if need be.
Check the wiring
The wiring is really simple. Just look at the diagram on the box of the switch. The wires run into the junction box. Make sure to attach the wires to the switch. Then attach the switch to the box. Finally, you must put the cover plate on. The starting capacitor must be left as is. No need to alter it.
Step-4: Perform the required tests
Now you just need to test if your DIY vacuum is working. You can make a T fitting out of ¼ inch I.D plastic pipe and hot glue. Connect the T fitting to the vacuum gauge. See if it can hold the air. Next, you need to test the pressure. You need to be able to get about 27 inches of mercury. It is more than good enough.
Q: Will Vacuuming an AC System Without a Pump Be Sufficient?
Ans: While it may not be ideal the process can certainly get the job done. If you follow the procedures stated above carefully you will get results. But this process should only be utilized when there are no other options left.
Q: Will a DIY Pump Be Enough for Most Projects?
Ans: A DIY pump will generate about 27 inches of mercury pressure. This can easily handle most tasks. But if your project requires a huge amount of pressure then you’ll be better off buying a new one.
After installation, you might want to check if your ac is working properly. If it is not then look at our steps carefully. Verify if you’ve done everything accordingly. If the answer is yes then you must vacuum your ac system with a pump.