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I just replaced my ac compressor and am trying to charge it. I am having difficulties getting it to take more R-134. I've put about 10 oz in the system so far. If you watch this video here you can see the problem. The high side isn't getting the pressure should have.
It's about 30 degree outside, I'm not sure if that matters.
 

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Welcome @Gillman331 ....I'm not an HVAC tech but I replaced a a/c compressor, drier, condenser this summer and had no problem charging the system. Did you use a vacuum pump to get all the moisture out and was the system able to hold a vacuum for an extended period? I used a scale to ensure the correct amount of 134 is put into the system. Temp might be an issue but maybe someone else can chime in on that.
 

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Yup I pulled a vacuum down to ~-30mmHg for 2 hours and held it for 24 with no change in pressure.
 

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A couple of things and some questions.

I appologize ahead of time if you already know these things but I figure it is always best to assume people don't.

It is usually harder to charge when the ambient temperature is cold. You can speed the charging process up by warming the can of refrigerant. As you transfer the refrigerant from the can to the system the can will get even colder - so it fights against you. Colder can equals lower can pressure. I always warm the cans if I can - summer or winter. I always use a cup of warm water when trying to charge a system using these small cans. You can hooked up your gauges and let it start servicing the system and them simply put the can in a (32oz ish) cup of hot tap water. This will warm the refrigerant in the can, raise the can pressure, and make it go in the system faster. You may need to change the water in the cup twice if it is cold outside. This will allow you to get almost all of the refrigerant out of the can.

The other thing that is kinda making it go slow is the low pressure switch. The AC system has a safety switch that will shutoff the compressor if the system pressure gets too low (like you have a leak or the system is low on refrigerant) to keep the compressor from running without refrigerant and the oil it circulates through the system to keep the compressor lubricated. I do not know what year Pilot you have but on the 04 the switch is on the passengers side engine compartment in the ac pipe. It is a simple 2 connector switch. You can disconnect the switch and jumper the two connections in the connector to bypass the low pressure switch making the process go much faster. A straightened out paperclip works good just don't let it ground out against something. Once bypassed the compressor will run constantly and not cycle.

It also helps if you can speed up the engine during charging. This makes the compressor run faster and create more suction.

Now for the questions - which you may want to skip if what I said above works.
What year is your Pilot?
Did you change anything other than the compressor? Receiver Dryer etc
Why are you putting a compressor on it? Was it leaking or did it fail?
 

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Have you worked on vehicle AC before or is this a first time?

What source/brand is the compressor?

Did the previous compressor completely fail internally? If so, did you replace all the components that might be contaminated, such as expansion valve, header filter, desiccant, condenser, evap, or just trying a compressor swap?

Low/Low = bad compressor, or low refrigerant charge most of the time. Since you know the charge is low Since the low side pressure is dropping while compressor is cycling, and the high side is creeping up, that's a good sign. Are you sure your can is letting refrigerant in? Shake the can sideways a bit, do you see liquid entering the sight glass, then clearing out as it is drawn into the low side? It can take a while to draw out all the refrigerant, and I have had cheap can taps restrict the flow. I have no problem shaking the can sideways and ensuring its moving. You dont want to slug the low side with liquid (as too much can damage the compressor), just a little bit at a time to ensure its going in and clearing through the sight glass.
 
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