6 ms·

If they’re using copper, changing materials would probably save money. Copper is comparatively expensive. I suspect your premise that they are using mostly copp

by eloff 4y ago

If they’re using copper, changing materials would probably save money. Copper is comparatively expensive. I suspect your premise that they are using mostly copper is incorrect, but then I write software for a living, what do I know.

loeg 4y ago
Copper is (very) effective for conducting heat. Aluminum is also pretty effective but obviously has different material properties than copper. It might be a good fit here; I don't work in the space.
- kazen44 4y ago
  aluminium also has the problem that it is a dissimaler enough metal from most other plumbing hardware (being either made of brass, copper or steel) that it will result in the buildup of a lot of gunk because the aluminium disolves.
  - eloff 4y ago
    That’s galvanic corrosion, but it’s usually an issue in water. I don’t know that it would be a problem with refrigerants, likely not.
- bluGill 4y ago
  Aluminum generally has fatigue limits that mean it will fail eventually, releasing refrigerant (which is normally an environmental disaster)
  - dylan604 4y ago
    what qualifies as a disaster? the amount of refrigerant in a consumer unit just doesn't seem like a lot even if 100% of it was released. if it was a continuous supply, then maybe it could get disaster level, but these are closed systems with a finite amount. at these levels, it seems to me that just driving one's car would qualify as an environmental disaster.
    - Retric 4y ago
      The issue isn’t just the 1st one that breaks the issue is the other 100,000+ that do.
    - adonovan 4y ago
      If a typical large split system has about 10Kg of R410A (GWP = 2000x CO2) that's about 20 metric tonnes of CO2. Compare to 5 tonnes for an average passenger car per year. So a leak is like four years of driving a car. Is it a disaster when an invisible odorless gas escapes and no-one notices? Or when a tree falls in forest? Not on its own, but our entire crisis is a pile of sand grains each too small to count.
      - dylan604 4y ago
        My real point was accident vs disaster. Whether anyone knows about it or not (someone will know when the AC doesn't work and the repair tech sees it being empty). If one house looses coolant, then I'd call it an accident. If a vendor has a major problem during manufacturing so that the majority of units fail, then maybe we can use bigger words.
  - dashundchen 4y ago
    The newer refrigeratants that require higher pressures are much better for ozone and have a lower global warming potential. Pentane and isopentane, R601 being one of them (of course flammability is a problem) and R744 which is just CO2.
pjc50 4y ago
Copper has long been the choice for piping because it's soft enough to bend without cracking. The obvious #2 choice, stainless steel, is often even more expensive. (I don't like the standard HN analysis technique of assuming that another field has made a really basic error that can be spotted by an autodidact from outside)
- deleted 4y ago
  [deleted]
- etrautmann 4y ago
  While I generally agree with your response to the perceived arrogance - shouldn’t we all ask if we can do better than assuming someone else is an expert and has fully optimized a solution? As long as we approach new domains with a sense of humility and respect I think it’s desirable to always be looking for better solutions.
  - mindslight 4y ago
    > assuming someone else is an expert and has fully optimized a solution? I wasn't offering my own singular expert [0] opinion, but rather pointing out what I've observed the entire industry has seemingly converged on. Despite being subject to the hyper-cost-optimization of the consumer market, every refrigeration appliance I've seen still uses copper heat exchanger tubes and copper piping. I would welcome someone chiming in saying something like "actually I work in HVAC and things are moving towards aluminum heat exchanger tubes and stainless piping" or "that's already the case for most new building-scale systems", because I'd learn something new. But "just asking questions" based on one single material property isn't particularly helpful. And yeah, copper has gotten expensive. That has helped some new technologies displace it (eg PEX), but copper is also still used where it's needed (eg PEX and PEX fittings over 1" nominal (which is equivalent to 3/4 copper) are prohibitively expensive for some reason). [0] In fact, I'm not a refrigeration professional, and have yet to pretend to be one. I just tend to look at how things are built.
- eloff 4y ago
  First off, I was upfront about my ignorance. Secondly, copper is way more expensive than stainless steel, unless I’m missing something. More than 8x according to random websites on Google. I’m sure there is a reason copper is used, but if the industry has to find an alternative, it would likely be cheaper.

by eloff 4y ago

loeg 4y ago

Copper is (very) effective for conducting heat. Aluminum is also pretty effective but obviously has different material properties than copper. It might be a good fit here; I don't work in the space.

kazen44 4y ago
aluminium also has the problem that it is a dissimaler enough metal from most other plumbing hardware (being either made of brass, copper or steel) that it will result in the buildup of a lot of gunk because the aluminium disolves.
- eloff 4y ago
  That’s galvanic corrosion, but it’s usually an issue in water. I don’t know that it would be a problem with refrigerants, likely not.
bluGill 4y ago
Aluminum generally has fatigue limits that mean it will fail eventually, releasing refrigerant (which is normally an environmental disaster)
- dylan604 4y ago
  what qualifies as a disaster? the amount of refrigerant in a consumer unit just doesn't seem like a lot even if 100% of it was released. if it was a continuous supply, then maybe it could get disaster level, but these are closed systems with a finite amount. at these levels, it seems to me that just driving one's car would qualify as an environmental disaster.
  - Retric 4y ago
    The issue isn’t just the 1st one that breaks the issue is the other 100,000+ that do.
  - adonovan 4y ago
    If a typical large split system has about 10Kg of R410A (GWP = 2000x CO2) that's about 20 metric tonnes of CO2. Compare to 5 tonnes for an average passenger car per year. So a leak is like four years of driving a car. Is it a disaster when an invisible odorless gas escapes and no-one notices? Or when a tree falls in forest? Not on its own, but our entire crisis is a pile of sand grains each too small to count.
    - dylan604 4y ago
      My real point was accident vs disaster. Whether anyone knows about it or not (someone will know when the AC doesn't work and the repair tech sees it being empty). If one house looses coolant, then I'd call it an accident. If a vendor has a major problem during manufacturing so that the majority of units fail, then maybe we can use bigger words.
- dashundchen 4y ago
  The newer refrigeratants that require higher pressures are much better for ozone and have a lower global warming potential. Pentane and isopentane, R601 being one of them (of course flammability is a problem) and R744 which is just CO2.

pjc50 4y ago

Copper has long been the choice for piping because it's soft enough to bend without cracking. The obvious #2 choice, stainless steel, is often even more expensive. (I don't like the standard HN analysis technique of assuming that another field has made a really basic error that can be spotted by an autodidact from outside)

deleted 4y ago
[deleted]
etrautmann 4y ago
While I generally agree with your response to the perceived arrogance - shouldn’t we all ask if we can do better than assuming someone else is an expert and has fully optimized a solution? As long as we approach new domains with a sense of humility and respect I think it’s desirable to always be looking for better solutions.
- mindslight 4y ago
  > assuming someone else is an expert and has fully optimized a solution? I wasn't offering my own singular expert [0] opinion, but rather pointing out what I've observed the entire industry has seemingly converged on. Despite being subject to the hyper-cost-optimization of the consumer market, every refrigeration appliance I've seen still uses copper heat exchanger tubes and copper piping. I would welcome someone chiming in saying something like "actually I work in HVAC and things are moving towards aluminum heat exchanger tubes and stainless piping" or "that's already the case for most new building-scale systems", because I'd learn something new. But "just asking questions" based on one single material property isn't particularly helpful. And yeah, copper has gotten expensive. That has helped some new technologies displace it (eg PEX), but copper is also still used where it's needed (eg PEX and PEX fittings over 1" nominal (which is equivalent to 3/4 copper) are prohibitively expensive for some reason). [0] In fact, I'm not a refrigeration professional, and have yet to pretend to be one. I just tend to look at how things are built.
eloff 4y ago
First off, I was upfront about my ignorance. Secondly, copper is way more expensive than stainless steel, unless I’m missing something. More than 8x according to random websites on Google. I’m sure there is a reason copper is used, but if the industry has to find an alternative, it would likely be cheaper.