So my 99 Blazer is blowing warm air and I have not had it checked by a professoional as of yet. But I wanted to at least get an idea of what the problem could be.

Here is what I have checked and done so far.
1. Compressor and crank seems to be working fine when I add a can of 134a with lead stop.
2. The charge only holds for a few days.
3. I have been reading my Hynes manual on replacing certain components.
4. what would you suggest replace the accumulator, condensor?
5. how much are the parts approx?
6. what is a dryer? where is it located and what is it used for?

Much thanks to all my blazer friends out there for any help that you give me and suggest.

 

First of all since you have very little knowledge of an air conditioning unit I would recommend you get a good shop to fix it.
Many A/C problems I see are caused from people who don't understand these systems, then try to fix them. On these vehicles today with the synthetic freon you can't do like the old days & R-12. You just can't add a can of R134A.
I'm most likely wasting my time posting this, but on more time I will try to reach a few of you.
First off I graduated with a certification in refrigeration from a Jr College in the 1970s. I work as a Refrigeration Tech for a contractor with the Department of Defense. I also worked automotive A/C from the 1970s to the 1990s.
I hold a Type I & II high pressure EPA License & I was also ASE Certified in auto A/C.
These new freons the synthetics are made up of different compounds. When they leak they separate, So what you have left is only parts of the whole. The other thing is these freons & systems need to be charged to the exact amount listed for the vehicle. Just an 1/8th of an ounce over charge will lower the cooling efficiency. The charge has to be exact to work properly. Over charge by just a little taxes the system IE compressor failure.
Why to they sell freon over the counter at Walmart & such. Well it helps generate money for not only the freon manufactures but for the whole industry.
So anyway, to answer your question about a DRYER. On a Blazer it is the tank that is next to the heater core/A/C housing. A DRYER has a chemical & filter that filters & drys an moisture in that system. Now too much moisture it plugs up & you end up with little to no liquid going to the Evaporate liquid is what draws the heat out of the car. As the liquid heats it turns to vapor & returns to the condenser where it is cooled & returns to liquid.
Anyway, I hope this helps.
I would be more than happy to write up A/C operation but I just feel I waste my time trying to tell people the truth about their A/C troubles. A/C Units require expensive tools & a lot of knowledge to repair CORRECTLY. Sometimes you can shade tree mechanic them for a short while but the end result is either you or whoever is unlucky enough to buy you vehicle gets stuck with a high dollar repair bill or NO A/C.
I don't even work on my A/C Units on my vehicles because it is cheaper to have it done correctly by a shop that has all the correct equipment.
One other thing they don't tell you is how hazardous these synthetic freons are. When I worked as a Tech for the DOD Contractor we were required to wear full chemical suits any time we worked with the synthetic freons. There are many different ones not just 134A.

 

Thanks for the advice. I have two blazers without ac. one charged fine but went out when the thermastat got clogged and never worked arter replacing the other charged fine when i took it to the shop but did not work after two days. im going to find a more reputable shop and have the do both at maybe a discount. i dont mind working on my own trucks and perfer to. but not very comfortable with ac systems.