Home › AC Refrigerant › Questions to ask your technician
Refrigerant work is close to invisible to the customer. It happens inside a sealed system, using instruments you do not own, measured in units you have no way to check. These questions make it visible.
A note on tone, because it matters: this is not a list for catching someone out. Most technicians answer all of it without hesitation, and a good one volunteers half before you ask. If a question here produces irritation rather than an answer, that itself is information.
This page is built to be readable on a phone during a service visit. Nothing here needs to be printed, and none of it needs to be asked in order.
Identifying the system
- What refrigerant does my system use?
It determines the cost of every refrigerant line item on the quote, and it is printed on the equipment. - Can you show me where that is listed on the equipment?
A refrigerant type is a fact on a nameplate, not an opinion. Seeing it takes ten seconds. - What is the expected total refrigerant charge for this model?
It is in the manufacturer’s documentation, and it is the number that makes the amount being added meaningful.
The diagnosis
- How much refrigerant are you adding today?
Amount added compared with total charge tells you how much was missing. Without both numbers, neither means anything. - What measurements showed that the system was low?
Low charge is diagnosed with superheat and subcooling readings against the equipment’s own charging chart, not by pressure alone. - If refrigerant is missing, where do you think it leaked from?
Refrigerant circulates in a sealed loop. If a meaningful amount is gone, it went somewhere. - Did you perform a leak search?
Distinguishes a leak that was actually found from one that was inferred. - What leak detection method did you use?
Electronic detector, UV dye, bubble solution, and nitrogen pressure testing differ a lot in what they can find and how long they take.
The repair approach
- Are you repairing the leak before adding refrigerant?
Adding refrigerant to an unrepaired leak means paying for refrigerant that will escape again. - If not, why?
There are legitimate answers, such as an emergency stopgap during a heat wave or a leak that needs a part on order. It is reasonable to hear the reason. - If a different refrigerant is being proposed, exactly what refrigerant is it?
Retrofits are legitimate but specific. You want the actual designation, not just ‘a replacement for R-22’. - Is that refrigerant approved for this equipment?
Refrigerants are not interchangeable because their pressures look similar. Approval is equipment-specific. - What components or procedures are required for the conversion?
A real retrofit usually involves recovery, often an oil change, and sometimes a metering-device change. If none of that is mentioned, ask more.
The bill
- Is refrigerant billed per pound or as a flat charge?
Both are normal. You just want to know which, so the line item can be checked. - Is the refrigerant amount actually weighed or measured?
Charge is properly added by weight. A scale gives you and the technician the same number. - Are diagnostic and leak-detection charges separate?
They are separate work and are often billed separately, which is fine. Double-billing the same task is not. - Are recovery and evacuation included?
Any time the sealed system is opened, recovery is required. Knowing whether it is in the price avoids a surprise line.
Warranty and the bigger decision
- Is the leaking component under manufacturer warranty?
Evaporator coils frequently carry a 10-year parts warranty. This single question changes more quotes than any other on this list. - What warranty applies to this repair?
A leak repair that fails in three months should not be a second full-price visit. - If this is an older R-22 system, what would repair cost compared with replacement?
On an older system with a large recharge plus a component repair, the repair and the replacement can be closer together than they first appear.
Most technicians answer all of these without hesitation, and a good one will volunteer half of them before you ask. The point is not to test anyone. It is that refrigerant work is invisible to the customer, and these questions make it visible.
Where this site stops
We will help you understand your equipment, read your invoice, and ask better questions. We will not tell you how to buy refrigerant, connect gauges, or charge a system. Opening a sealed refrigerant circuit requires EPA Section 608 certification under federal law, and there is no homeowner exemption. Venting refrigerant is separately illegal. This is genuinely a licensed-technician job, and the reason is legal as much as technical.
Related: General HVAC quote checklist · Check a refrigerant quote · Find an HVAC pro
Frequently asked questions
What is the single most useful question to ask?
Whether the leaking component is under manufacturer warranty. Evaporator coils frequently carry a 10-year parts warranty, and that one question changes more quotes than any negotiation will.
Is it rude to ask a technician this many questions?
No, and you do not need to ask them all. Pick the few that fit your situation. Most technicians would rather explain the work than have a customer approve something they do not understand.
What if a technician will not show me the refrigerant type on the equipment?
That is a reasonable thing to be shown — it is printed on the data plate and takes seconds. If it is refused without explanation, getting a second opinion is a proportionate response.
Sources & verification
✓ Verified against a manufacturer, regulator, or standards source
- EPA, “Homeowners and Consumers: Frequently Asked Questions” (HCFC phaseout) — epa.gov
Last reviewed 2026-08-31. How we verify what we publish →
