I just had a guy here to service my heat pump. It’s 13 years old, hasn’t given us any trouble. Early on it was regularly serviced (though I think that amounted to just opening the covers and clearing out any leaves) but then the company I bought it through went bust. So I thought “hmmm… 10 year life expectancy and it’s now 13, probably a good move to get it checked out.”
Long story short. The unit uses R22 gas. This, says the technician, is no longer available and so when anything fails on this unit that’s it. Replacement is the only option.
Now I get that those old gasses were not the nicest things for the environment, and the new ones are kinder and more efficient so you can go a bit lighter on the compressor. He confirmed that the new one will use less and can heat to a higher temperature (the current unit is limited to 60 degrees). Also you get nice stuff like remote control via an app on your phone.
But it got me thinking. What about all these old systems that use these old gasses. Does this mean that I won’t be able to get the A/C in my old Hyundai regassed?
Taking what he said at face value, if anything mechanical goes wrong with an old fridge then that’s it. Chuck it away (sounds like a lot of pollution to me) and buy a new one. New compressors aren’t suitable for the old gas and vice versa.
My father just had an old AEG freezer repaired and converted to the new gas. Let me explain, this freezer was bought in the mid 90s, when AEG was still properly German. It is a chest freezer, something that is becoming increasingly rare. And the thing lasted 30 years and was still working, except the rubber bushings the compressor sits on had perished completely. This meant new compressor… which meant new gas type. The conversion was successful and according to the tech, the freezer should last another 30 years.
So, I think it is quite feasible to convert a heat pump to something else. The question is whether it is economically viable.
Probably the trick is to find somebody not too tightly tied to the manufacturer. Kwikot have no interest in doing such a job because they’d much rather sell me a whole new unit. They measure their business in sales, not in keeping old stuff running past it’s life expectancy (which this one now is).
And there’s a markup too for the guy who actually buys it from them and installs it for you.
You can’t make a living fixing things! (I speak from personal experience)
I don’t have a problem with this as long as the stuff is recycled responsibly.
Maybe the tech misspoke. I think what is happening is that replacement compressors that use R22 gas is no longer available. That isn’t only the gas, but also the combination of gas and lubricating oil. If you use the wrong oil with the compressor, it can get destroyed pretty quickly.
Converting the system also requires very carefully cleaning out the old lubricant. At least, that is what I heard. In some cases it is almost impossible to do. Case in point, this little BMW i3 EV we bought a year ago. Runs R134a, with POE oil. You must never under any circumstances get any PAG into the system, which literally means buying new clean equipment if your existing equipment has been used on a PAG system.
As I retire at the end of the year, and as the current pump is now 14 years old (the tech tells me he thinks it is the oldest running Kwikot pump in Joeys), I asked for a quote for a replacement.
Of course once I got the quote I googled for a data sheet.
The new unit uses R407c, which is much friendlier to the ozone layer than R22. R22 is still available at a shop just up the road from me.
So I can’t stop and I google R407c. Hmmm… this is also being phased out according to the Kigali Amendment of the Montreal Protocol. Because it has a high GWP - Gobal Warming Potential. By this metric it is only slightly better than the R22 it has replaces.
AIUI the GWP is expressed as an equivalent mass of CO2. So CO2 itself has a GWP of 1. 1 kg of CO2 causes as much global warming as 1kg of CO2.
R22 comes in at 1960 - IE 1 kg of R22 causes as much global warming (due to infrared) as 1960 kg of CO2. R407c has a GWP rating of 1774. So better, but not by a lot.
Both gasses are in the class HFCs - Hydrocfluorocarbons.
In the USA all C̶F̶C̶s̶ high GWP gasses are ruled out for most applications since Jan 1st. The regulation lists various applications and says whatever gas you use must m̶e̶e̶t̶ ̶a̶ ̶G̶W̶P̶ ̶s̶c̶o̶r̶e̶,̶ ̶a̶n̶d̶ ̶t̶h̶a̶t̶ ̶s̶c̶o̶r̶e̶ ̶i̶s̶ ̶o̶n̶e̶ ̶t̶h̶a̶t̶ ̶m̶o̶s̶t̶ ̶C̶F̶C̶s̶ ̶(̶a̶n̶d̶ ̶c̶e̶r̶t̶a̶i̶n̶l̶y̶ ̶R̶4̶0̶7̶c̶)̶ ̶w̶o̶n̶’̶t̶ ̶e̶v̶e̶n̶ ̶g̶e̶t̶ ̶c̶l̶o̶s̶e̶ ̶t̶o̶.̶ have a GWP of 150 or less.
The Montreal A̶g̶r̶e̶e̶m̶e̶n̶t̶ Protocol i̶s̶ ̶r̶e̶a̶l̶l̶y̶ ̶a̶b̶o̶u̶t̶ ̶t̶o̶t̶a̶l̶ ̶p̶h̶a̶s̶e̶ ̶o̶u̶t̶ ̶o̶f̶ ̶C̶F̶C̶s̶ ̶a̶n̶d̶ ̶r̶e̶p̶l̶a̶c̶i̶n̶g̶ ̶t̶h̶e̶m̶ ̶w̶i̶t̶h̶ ̶t̶h̶e̶ ̶f̶a̶r̶ ̶l̶e̶s̶s̶ ̶i̶m̶p̶a̶c̶t̶f̶u̶l̶ ̶H̶F̶C̶s̶.̶ ̶ phases out the use of gasses that damage the Ozone layer. T̶h̶e̶ ̶K̶i̶g̶a̶l̶i̶ ̶A̶g̶r̶e̶e̶m̶e̶n̶t̶ ̶u̶p̶d̶a̶t̶e̶s̶ ̶t̶h̶e̶ ̶t̶i̶m̶e̶l̶i̶n̶e̶s̶ The Kigali amendment recognises GWP as well (thus changes Montreak to be about warming and ozone), updates the timelines, and implements a staggered scale for old industrialised countries, new industrialised (eg China and Brazil), and developing countries. Each group has a different deadline. Old industrialised countries are committed to phasing out 85% of their 2013 use of C̶F̶C̶s̶ stipulated gasses by 2036. Countries with high average temperatures may request a waiver.
“High average” is defined as at least two consectutive months at 35 deg or higher over 10 consecutive years.
So these gasses are not verboden (well in the US they will be by 2028) but they are being discouraged.
Now that I’ve taken all this in I feel fairly sure that I’ll be able to refill that pump (if that’s necessary) for another 10 years. But the reading was interesting, especially that the US are going by their own regulations here, and those are not based on the type of gas but the measurable damage that gasses can do. S̶o̶ ̶y̶o̶u̶ ̶c̶a̶n̶ ̶u̶s̶e̶ ̶C̶F̶C̶s̶ ̶i̶n̶ ̶t̶h̶e̶ ̶U̶S̶,̶ ̶a̶s̶ ̶l̶o̶n̶g̶ ̶a̶s̶ ̶i̶t̶ ̶m̶e̶e̶t̶s̶ ̶a̶ ̶G̶W̶P̶ ̶m̶e̶a̶s̶u̶r̶e̶ ̶w̶h̶i̶c̶h̶ ̶i̶s̶ ̶v̶e̶r̶y̶ ̶l̶o̶w̶ ̶f̶o̶r̶ ̶C̶F̶C̶ ̶t̶y̶p̶e̶ ̶g̶a̶s̶s̶e̶s̶.̶
HFCs may still be used in the US, but only if they meet a very low (for HFCs) 100 year GWP rating.
Nice summary. Using the CO2 yardstick for GWP is quite common. We also use that to turn methane emissions into an apples for apples thing when making comparisons.
R32 sits at 675. Much better, but still not excellent. And I am unsure if it can be used for heat pumps… probably should be fine though. Right?
Thanks. Actually I just made some revisions - which is why post now looks like something that has been dragged through a bush backwards. I was on the right path with GWP, but it is generally calculated as the effect of X kg of CO2 over 100 years.
I did ask about simply regassing my pump with a newer refrigerant. I was told that different gasses are differently compressible and so the compressor has to be matched to the gas. Otherwise things may go bang or not work very efficiently.
