Do You Charge ac on High or Low Side

Last updated on April 5th, 2022 at 06:48 pm

Do You Charge ac on the High or Low Side? Whenever an AC system loses its ability to cool perfectly, then it’s time to recharge the system with a new refrigerant.

To answer the question, do you charge ac on the high or low side? You need to understand that the high side fitting is located between your AC compressor and condenser, which is the larger of the two fittings.

However, you need to consult the service manual to verify the exact location where the low-side service port can be found.

But if hooking a can of refrigerant with a single hose/gauge to your car, then you will use the low side. also read this on Does AC Affect Engine Power and how much does it cost to remove freon from the car if you are interested in those.

Do you charge AC on high or low side HVAC?

In case the system has a liquid line or a king valve, then you can charge into the liquid line. But if not, then go to the suction.

However, note that it isn’t always possible to do, though charging into the high side is fine, at some point, you will have to switch over to the low side.

But in case you are installing refrigerant inside an operational system, then charge vapor only via the low-pressure port.

Also, in case you are installing the refrigerant after you have done a repair and evacuation, then charge liquid into the discharge gauge port or even the liquid gauge port and then switch to vapor charging once you start the unit.

However, if you try to install the liquid into the low-pressure port at any time, then you will risk destroying the valves in a recipe.

This is because the compressor and maybe washing out the oil from the compressor sump may lock up the compressor.

Can You Charge Ac On High Side?

Yes you can! But high side should not go beyond 350psi while adding refrigerant, but if it’s higher, then stop adding refrigerant and let it stabilize, and if it does not stable, then spray water on the condenser to lower pressure.

However, to open the 6Nm cap, then a 17 or 19mm deep socket will do. However, when tightening, be sure to not over tighten it.

Note that the pressure reading that will come from the low side should be between 25 and 30 psi, while the high side should be between 200 and 250 psi. in case you see the AC low side to be high, high side to below, then such as the low side is 100 and the high side is 150, then there might be issues with any of the inner components.

However, the possible reasons could be having an excessive amount of Freon which is going to the evaporator.

Sometimes it could be a problem with the orifice tube, or it could also be a failed thermal bulb that is unable to pick up the temperature signals.

Note that this tube works as an expansion valve that regulates the refrigerant amount that is flowing to the evaporator.

This means that when its opening becomes bigger than the usual size, then more refrigerant goes to the evaporator which will now create pressure discrepancies.

Also, this same problem arises whenever the o-ring seal outside of the orifice tube wears out.

But before you decide to replace the compressor, other components that you may check includes the pressure switch, expansion valve, and the compressor clutch. However, the switch is located near the expansion valve.

While you use an Ohmmeter to observe if it is giving the correct reading. You should also check if the compressor clutch engages and rotates the compressor whenever the AC is on.

So whenever all of these components appear to be working fine and the AC low side high, high side low problem persists, then you may need to change the compressor to fix the unit.

What Happens If You Charge Ac On High Side?

In case you notice that when you measure the pressure on the low side of your AC and is going higher 100, while the pressure on the high side is down to around 150 or even lower, then note that you may have a problem with the low side being high and the high side being low.

This simply means that something is wrong inside the air conditioning unit itself which is throwing this off.

Can You Charge Ac In Cold Weather?

Sometimes when it gets to the end of summer, you may have observed your car’s air condition system not cooling as efficiently as it should. And maybe you were very busy that you decided that you won’t worry about it whenever you need the air conditioner. The question is, can it be done in winter? Below are some things you should know.

Charging your AC When It is Above 75 Degrees

Experts advise that you wait until it is 75 degrees or even higher to have your air conditioning unit in your car recharged. Note that this process goes by many names which include refilling the Freon or refrigerant, topping off the AC or recharging the AC.

However, regardless of what it is called, it is highly advised to wait until it warms up outside. Indeed, the refrigerant’s weight will change when it is cold out as it contracts in the cold. Note that this will cause it to give off inaccurate readings in cold weather. Once this happens, it becomes hard to determine how much is already in your system, how much that is needed and how much has been added when adding in these elements.

Charging your AC When It is Below 75 Degrees

Sometimes there may be instances where someone cannot wait for the weather to increase and the car’s AC needs to be recharged, even in the dead of winter. Though it is advised that you wait until it is 75 degrees out, but a mechanic can recharge the system once the correct steps are taken.

The mechanic will have to store the car in a warm, heated garage. The mechanic will then have to first heat your AC system and the refrigerant they are using. Remember that refrigerant does expand a little in the heat, this means that they will have to account for this whenever they recharge your system.