Those who operate in the HVAC-R industry will be familiar with refrigerant recovery, but changes occurring within the sector means that engineers who carry out refrigerant recovery must be aware of the potential dangers surrounding the type of refrigerant they’re working with.
Engineers that have worked with refrigerants for many years will probably remember a time when refilling systems with new refrigerant was commonplace, and there were even instances where it would be used as cleaning agent.
This isn’t to say that engineers who operated during the 70’s, 80’s and 90’s were using unethical working practices, it was simply a sign of the times.
However, as the world looks to unify to reduce the carbon footprint, the HVAC-R industry is playing its part in ensuring that only refrigerants with a low global warming potential are used.
It’s also important to ensure that when using items such a refrigerant recovery machine, engineers are only using devices that are recommended, and not cheap substitutes.
The Changes Being Made in Relation to Refrigerant
As the changes being made in the industry are related to reducing damages to the ozone, the F-Gases being phased out are as follows:
- CFCs: R11, R12, R502 etc.
- HCFCs: R123, R22 etc.
- HFCs: R134a, R507, R407F etc.
CFCs are banned, whereas HCFCs have been phased out. The phasedown of HFCs begins in 2019, and A2L refrigerants will be used moving forward.
The use of A2L refrigerants means that there is more scope for refrigeration systems to be used around the world, but those who carry out freon recovery as part of their role need to ensure that they’re using a refrigerant recovery unit in the right way.
Although A2L refrigerants have a lower toxicity and is only mildly flammable, engineers still need to ensure that they’re also appeasing customers as well as staying safe when using a freon or AC recovery machine.
Factors That Need to Be Considered
Many engineers will be familiar as to what changes are taking place, and what approach should be taken when working with a refrigerant recovery cylinder. However, this doesn’t mean that assumptions should be made, and if there is any doubt, then it’s always worthwhile taking some time to give yourself a primer.
Certification: Anyone operating within the HVAC-R industry needs to hold the relevant credentials, but if an engineer carries out several roles, then it can be worthwhile clarifying that all training and certification is up-to-date/
Assessment: Although A2L refrigerants are only mildly flammable, it’s still important to ensure that the working conditions are safe, and the presence of an A2L refrigerant doesn’t pose a threat.
Only Use Professional Equipment
It goes without saying that many companies and engineers that operate in the HVAC-R industry will ensure that when recovering refrigerant, they’re only using professional equipment.
However, there are some that offer inferior products at a lower price, and while this can be attractive, it could also be potentially dangerous.
Not only is cheaper equipment destined to break down, but it could also mean that it’s not operating by the same safety standards of New Zealand. Cheap equipment will often only focus on the bottom line, and not the safety of the engineer using it.
As such, it’s important that checks are made when souring items like an AC recovery machine. These checks are nothing complex, and for the most part companies and engineers will already be making these checks.
However, it’s important not to become complacent and ensure that assumptions aren’t part of the process when choosing an HVAC recovery machine.
Checklist for Recovering Refrigerant
When recovering the refrigerant, it’s important to establish what type is used and whether the refrigerant will be put back into a primary system or another system.
Engineers need to ensure that they’re fully aware of how to operate the refrigerant recovery unit and are referring to guidance when necessary.
Using dirty freon recovery equipment can mean that operation is short live. Even dust particles can be problematic, as they could potentially contain metal, which when accumulated, go on to hinder the machine. Not only is this inconvenient, but it can also be costly,
When recovering the refrigerant, it’s important to ascertain as to how the refrigerant will be recovered. The methods used during freon recovery are as follows:
As the name suggests, refrigerant is collected while in a vapour state. Often slower than liquid recovery, vapour recovery will transfer the refrigerant to a refrigerant recovery cylinder, so it’s important to ensure that the pipes are short but as large in diameter as is possible.
Liquid recovery is much faster than vapour recovery but does have the potential to leave vapour in the system. The use of liquid recovery can only be deployed when moving refrigerant from one container to another.
When moving refrigerant in large quantities, push-pull recovery will be used. When the vapour is collected from the recovery unit, the liquid is pushed out of the HVAC system and back into a refrigerant recovery cylinder.
The discharge valve is switched to ‘recover’ which bypasses the condenser, which in turn creates a greater push pressure. To carry out this method, engineers will need access to an additional hose, sight glass and refrigerant recovery unit.
It is important that this method isn’t used in the following circumstances:
- The amount of refrigerant is less than ten points.
- The system is a heat pump
- The system contains a reversing valve.
- The system has an accumulator.
- The system doesn’t permit the generation of a solid column of liquid.
The Features of a Recovery Machine
Although the use of an HVAC recovery machine will have used oil in the past, nowadays such units are not only kinder to the environment, they’re also much lighter.
As well as the benefits it has in relation to portability and the effect on the environment, an AC recovery machine that doesn’t use oil is also able to collect more than one refrigerant, as well as not having to deal with maintenance that occurs with oil.
The features of refrigerant recovery unit will vary, but often include the following:
- Large Fan
- Large Condenser
- Small Size
- Purge Feature
- Contestant Pressure Regulator
Although the modern interpretation of a refrigerant recovery unit is more beneficial, it is still important to ensure that the equipment you use is suitable or the freon recovery being carried out.
The changes being made in the industry will mean that refrigeration is made possible without affecting the environment, but as customers may seen tags that include the word ‘flammable,’ it’s important to ensure that the right equipment is partnered with a professional approach.