Dual a/c system

[novanix]

Greetings,
I have recently vacuumed & recharged my a/c system, I have read the service tag on the engine & it had said that my van has a dual a/c system.
I did install the correct freon type & lubricant. However, only the back vents of the van are currently blowing ice cold, meaning. I did recharge the system, but only the rear. I did througly inspect under the hood to look for the other low pressure valve to install, I did though only find one. Thinking it was the front, I filled it up to the specified pressure etc..
Would anyone who might have done this before know where to find the valves to recharge the front system?

P.s its a 2001 dodge caravan

Thanks!

[RIP]

Yup. Dual A/C system with a single service point, single condensor, filter, and compressor. There are not seperate service points for the front and rear. You may have a blend door problem.

[novanix]

hmm, the sticker under the hood says dual a/c system, then it gives me two different pressure readings. I thought maybe there was 2 service ports... The, air is cold but only in the back, I haven't check either driver or passenger side. But I'll check it tomorrow & post more details.

I have been reading that there have been many defects with the 01 Caravans. That probably would explain why my ABS & Airbag light have been on for ages huh?

[webbch]

While a system CAN be charged by pressures*, you have to know what your doing and it's definitely not the preferred method, especially for someone new to A/C work. Pressure figures are typically ballpark figures that you shoot for from a working system, not something that is generally used to measure exactly how much refrigerant to add. Typically, you charge by weight, and is something the manufacturer specifies for refrigerant capacity. The preferred method is to have a tank of refrigerant and an electronic scale to measure how much goes in, but you can also get close by using a number of cans of R134a (pure, don't get anything with sealers in it).

My recommendation would be do evacuate the system (may need to take it to a shop to do this), then pull a vacuum again, and charge by weight this time. Your caravan calls for 46 oz. of R134a.

*There are two pressures you are typically interested in on an A/C system - the low side pressure and the high side pressure. A manifold gauge set will monitor these pressures while at the same time allowing you to add refrigerant. The fact that you were not aware of this tells me you probably used a kit in a can that you got at an auto parts store. It may even have had a gauge on it that is intended for hooking onto the low side port. These are commonly referred to as "death kits" for 2 reasons. First, they often contain the dreaded sealers that contaminate your system and eventually lead to the death of your a/c system. Secondly, since you are not monitoring the high side port - if there is a problem and the high side builds up extreme pressure, you have no way of knowing; it could result in bodily harm if the pressure relief valve isn't working.

[novanix]

I have had it vacuumed prior to installing the refrigerant, didn't use no sealants. Had check the pressure on both High/low this morning, both are in normal limits. I have done a/c systems in my other vehicles before, both of their a/c's are still running for over 2 years since the last refill.
Thanks for the advice, maybe i'll have the system looked at. Just to make sure there is no major problems.