Why won’t you sell me refrigerant?

Written by: Caroline Acebedo

Recently, we have had customers get very upset when they come in to buy refrigerant and realize that we cannot sell it to them. Why, you ask?

On January 1, 2018, the EPA rules changed.  It is now a requirement that anyone purchasing ANY refrigerant (R12, R134a, R1234yf) for use in an automotive system be Section 609 certified. This rule applies to any container over 2 pounds.

So basically, to meet the requirement, at least one person in your shop or parts store must be able to produce evidence of their certification. If you have multiple locations, you need a certified individual in every location where you intend to purchase refrigerant.

If you have ever been certified and you cannot locate your certification, you can contact MACS through their website (http://www.macsw.org) and they can search through their databases in an attempt to locate it. There is a fee of $10 for the search and replacement documents.

Another solution is to recertify (or get certified if you have never been). There is a lot of new information regarding the servicing of R1234yf refrigerants and information on best practices. The cost is only slightly more and you can take the test online. If you choose the online option, you will get an immediate score and if you pass, you’ll be able to print out your credentials so you can use them immediately. Here is the link to the test on the MACS website:



If you are not the online test taker type, you can find a proctored (Marks Air hosts these certification classes occasionally) class and get certified that way.  You can contact Caroline at Marks Air for more info regarding proctored classes.



Marks Air is hiring!


Job description:
Air conditioning mechanic specializing in mobile HVAC service, repairs, and installation.  ASE, MACS, & EPA 609 (for the safe removal of R-134a refrigerant) certifications will be required after training. EPA 608 Certification a plus.

Ideal candidates should possess strong work ethic and ability to work long hours during the summer season.  Also requires basic knowledge of mechanic hand tools and required mechanic tools per our list.
This position is primarily seasonal and will require long hours in the spring/summer/fall months.  Work will be Monday- Friday.  A positive attitude is required!
Health Insurance benefits will be offered after 90 days of full-time probationary employment.

Should you flush?

Written by:  Jim Garner

Hey! Do you think I should flush? In most cases, YES!!

Oh, yes, you should always flush the a/c system when you have a compressor failure. A clean system will help prevent the new compressor from failing.  Old driers, moisture in the system,  and internally damaged compressors can lead to metal and debris being transported through the system.   In some cases, the only way to remove those contaminants (short of replacing every component in the refrigerant loop) is to flush the system.

Debris can easily be seen in systems that have an orifice tube. Metal  and particles get lodged in the inlet screen.

One of the most common reasons a new replacement compressor fails is THAT contaminates ARE still in the system from a previously failed compressor. So yes. Flush.

The newer, R-134a compatible, parallel flow condensers cannot be flushed, they must be replaced as well as hose assemblies with  mufflers that cannot be flushed.



clogged orifice tubes

Orifice tubes clogged with debris


parallel flow condenser

parallel flow condenser

Keepin’ it green

Written by: Caroline Acebedo

Recently, Marks Air renewed our certification as a Green Star facility.  An industry-friendly program, Green Star encourages auto repair facilities to go above and beyond environmental compliance by using Best Management and Pollution Prevention strategies.

We take great pride in using environmentally responsible practices when repairing customers’ vehicles.  In addition to being green in the shop,  we “keep it green” in the office as well.  We recycle paper, plastics, and cans.  To save paper, we can email invoices, credit memos, and statements.

If everyone does their part in being green, we will all be able to enjoy a cleaner and safer environment.


Are you using the right type of o-rings?

Written by: Caroline Acebedo

The employees at Marks Air recently attended the Mobile Air Conditioning Society (MACS) annual training event and trade show in Orlando.  One of the many things we learned in training classes were the various differences in O-rings.  There are MANY different types of material being used to make o-rings.  There are companies out there trying to cut costs, and they are using materials that do not work well with system lubricants and refrigerants.  Some of the material being used will break down when exposed to refrigerant and lubricants and cause system leaks.  It is extremely important that you are getting your o-rings (as well as your parts) from a reputable source!

We are lucky that we have the various training events offered by MACS so that we can become educated on industry matters such as this.



A/C Mechanic in a can $29.95

Written by: Jim Garner

Have you ever been to an automotive parts store and noticed the large display of R-134a refrigerant?  If you read the fine print, under the large letters R-134a it says in small letters “with stop leak” or “sealant”?  Sounds like a great idea.  I can be an A/C mechanic for $29.95. WRONG! Problem is, most sealants are activated by air and/or moisture and it will crystallize in the system.  It will cause more harm than good. Once the crystallization occurs it can restrict the flow of oil and refrigerant through the entire a/c system. In most cases, the sealants cannot be flushed out to remove them from the system.  This can cause problems with the compressor, condenser, expansion valve, and evaporator, other components in the system.  It can cause blockages and high system pressures.  Also, when the technician recovers the system into his expensive recovery machine, the sealant can render it inoperable. It makes a lot more sense in the long run to replace the part that’s leaking. It may cost more at first, but it will save you time, money, and headaches in the future.


Got a Jones’?

Got a Jones’?

Written by: Buddy Ward


Ever wonder, has anyone worked on EVERY model out there? Although we do a variety of different vehicles, we can’t say we’ve seen them all.

We specialize in class 6, 7 and 8 trucks and other heavy duty vehicles, but still do our share of cars and light trucks. When we get something in that is new to us and might potentially be a challenge, we tend to fall back to the basics and call around to our extensive network of friends in the industry who might have experience with it.

One of our favorites is from Connecticut and works on vehicles we only see occasionally. We trust him to tell us, if he’s done one, whether or not the CHILTON or MITCHELL manual is correct and that 3 hour job is really a 6 hour job. And he calls us when he occasionally sees the heavy duty truck or bus.

We met the fine folks at Jones Automotive years ago at a MACS convention. Aside from the training we receive by attending MACS and other industry training events, the relationships we develop there are invaluable.

Its great networking and everyone learns something!

Lost Sales a lost art????

By: Otto Aliffi

Does your organization track reasons you have lost opportunities or business? If so, congrats for being farsighted enough to understand that the market will tell you what it wants, if you listen. When I ask most of our customers how they keep up with lost sales, I hear  3 typical responses:

  1. We don’t.
  2. We are only able to track lost sales of part numbers already in our system.
  3. We track all lost sales and opportunities.

I get way more of the first two than the last. It is important for every company to chart the reasons it loses business, as well as why it earned business!!  So get together and discuss what the customers are saying.

To flush or not to flush….that is the question

By: Caroline Acebedo

Anytime we see a compressor failure that has filled the system with debris, we flush the system.  However, if the system is full of metal fragments and debris, flushing might not be enough.  If system has a newer, parallel flow (R-134a) condenser, or a micro tube condenser it may have to be replaced to ensure that the system is clean.

If you are working with a tube and fin or serpentine condenser, you can effectively flush the condenser.  If you are working with a parallel flow condenser, it is a different story entirely.  While the multi-flow/parallel flow condensers are more efficient than the old tube style condensers, they cannot be effectively flushed!  The passages in the parallel flow condensers run back and forth across the core several times. Micro Tube condenser passages are smaller than the tip of a pen plus they are parallel flow.  Because these passages are so small, it is impossible to remove contaminants from the system.

If the condenser is not replaced and remains clogged with debris it can cause high head pressures and/or lack of cooling.  If the system continues to run with high pressure, it can cause excessive wear on the compressor and ultimately lead to compressor failure.

Although it makes a repair more costly to replace the condenser, it pays off to complete the job correctly the first time!


parallel flow condenser
parallel flow condenser
clogged orifice tubes
clogged orifice tubes


Does your vehicle have a cabin filter?

By: Jim Garner

One thing that is often overlooked and can have an effect on the cooling of your truck cab is the cabin air filter on a lot of late model trucks and cars. In fact, most people don’t even realize that they have one.  The filter cleans the air that comes through the ventilation system. It catches the dust, pollen, and other airborne materials. If the filter is not changed on a regular basis, it can become clogged and restrict the air flow. We have seen some filters so clogged with material that it was a wonder how they got any air flow at all. Once we make the customer aware that the filter is there and can be changed fairly easily, they will always have clean, cool air flowing through their cab. We have a good line of cabin filters in stock.

cabin filter cabin filter 2 cabin filter 3