I am very much a DIY’er and doing my own HVAC repairs have never been out of the question. Actually, I have rebuilt a couple of systems, less the pressurized parts of the system.
HVACs are great until they aren’t and the need for repairs always comes up at the worst possible time. It would be nice to know more details for those reasons.
If you ignore the direct question about charging an HVAC, there could actually be a small, slow leak in my system as it stands. That’ll get troubleshot in due time. (Still, I don’t think I have ever had a system that didn’t need the system to be topped off after a few years, even with no detectable leaks…)
It doesn’t seem difficult: Ensure system is at correct temperature; attach a gauge; depressurize/pressurize as needed.
There has to be some “gotchas” in there somewhere. The equipment is cheap enough and I am fairly sure I can source the correct refrigerant easy enough.
Aside from needing to store and manage a small supply of refrigerant and that there are some annoying risks (like a system freezing over, etc…), what cost factor and equipment am I not taking into account?
You most likely won’t be able to get the refrigerant through legitimate channels
I think you can get refrigerant from most gas supply stores, usually the same business sells welding supplies. I know you can exchange full bottles for empty there but I don’t know about the reverse.
If you live in the US you cannot legally purchase most domestic refrigerant without EPA Section 608 certification. Many supply houses will ask to see your cert card if they don’t recognize you.
Ok, I wasn’t aware of that.
The refrigerant recovery machine is around $500 entry level, you also need the correct tank and a good scale. That’s on top of the manifold, new refrigerant, vacuum pump, etc. I don’t know much about it but I looked into it once upon a time for automotive DIY and decided it was too costly to mess with.
You’ll need to pickup 608 type I certification to legally buy most refrigerants. It’s inexpensive, the exam is open book, and takes an afternoon to complete.
The “textbook” used is actually a useful reference if you’re just starting out. The material familiarizes you with common terminology, regulations technicians must follow, and the procedural basics for typical jobs, but the emphasis overall is how to handle refrigerants safely and avoid venting them into the atmosphere.
I started looking into that and if the price is right, it’s not that far-fetched. (After all, I did get my ham radio license mainly so I could legally transmit up to 1000W in some cases…)
HVAC repair seems to be a lucrative business so it may be something to do on the side. The certification would be a great way to start that, actually.
Thanks for the additional info!
Sure thing! Yeah the type I cert is an easy choice, same as 609 MVAC. If you’re considering the trade, you might choose universal (I, II, III) to save time. Exam is longer, closed book, and proctored, but not hard.
Among skilled trades, HVAC is notoriously demanding physically (especially residential, where you’ll spend a lot of time in attics and crawl spaces in hot weather) but consensus on hvac forums is that pay’s good and you’ll never be out of a job as long as you take care of your body.
Not a professional but Ive DIYed it. So the following may be oversimplified and/or not best practice.
You’ll need a gauge set so you can watch both the high and low side pressures. Your unit probably does not have ports to attach the gauges but they make some adapters that bolt on and pierce the lines. These work ok but will probably be another spot for leaks down the road.
You’ll need to figure out what refrigerant your unit has in it, there’s usually a metal placard somewhere that tells you this. This is how you’ll look up where your pressures need to be.
Finally you’ll need to source said refrigerant, which you likely cannot buy without a license or bribing someone.
The actual charging procedure I would look around on youtube for. It may vary depending on your type of unit but it’s usually pretty straightforward.
Does this apply to heat pumps?
I have no experience whatsoever with heat pumps. I think they do some black magic with reversing the refrigerant flow; so there is probably a whole other set of specs and procedures for those.
If the concept of a reversing valve is wholly alien to you, I cannot recommend you DIY your issue. Just hire someone, it goes beyond convenience or annoying risks, it’s your safety that I’m questioning. Frostbite, electrical shock, poisoning, risk of explosion, severe burns, suffocation, there are so many ways that trained techs get hurt or killed when they don’t respect the safety element. No way in hell am I going to tell a stranger on the internet to take that risk for themself or someone around them.
Please just hire someone.
Edit: just realized you’re not the OP. Still gonna leave this up. This kind of work is simply not suited to being done by non-professionals.
