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    Questions for the HVAC guys

    A few years ago we installed a new Goodman furnace with a 4 ton coil on it. We couldn't afford to complete the split AC system right then, so we left it for later. A year later, maybe two years ago, we remodeled our kitchen and I ran a gas line to the stove, removing the electric stove and freeing up a 50 amp breaker in the panel for the future AC condenser. Just recently, I got all the electrical conduit and wires pulled through the attic and installed the 110 and 220 volt disconnect for the new condenser.

    With outside temps fast approaching triple digits, we decided to bite the bullet and do this. Everything seemed to be coming together when my daughter-in-law's dad, a decades long HVAC guy, offered to connect the line set and complete the system setup. His company had a new Goodman 4 ton condenser in the yard and sold it to me for a fair price. Finally, it's happening! I picked up the line set, condensate pump, pipe, etc, etc, and yesterday morning we got to work.

    It wasn't long before I realized this guy didn't know beans about his trade, to put it nicely. We argued about how to flare out the ends of the pipe, how and where to bend it, on and on. Being family, I was really trying to give him the benefit of the doubt and even though I've been in residential construction for decades, I've had no experience with refrigeration plumbing so all I could do is trust his years of experience. I figured we just had a tense day, but overall, the system would be ok. We ate lunch and he left saying he'd return in a few days to pressure test and get the refrigerant lines charged with R410 A. After having some time to think about what we struggled with, reading and researching how this was supposed to be done, I'm sickened by this guy's ignorance and can't stand the thought of completing the system setup.

    I am deeply concerned about his braising joints. This isn't the end of the world, though. If after preassurizing the system with nitrogen and soaping the joints there are no leaks, which would surprise the heck out of me, I'll proceed.

    He didn't have the right flairing tool so he pounded a hammer type tool into the 3/8" liquid line on the coil. This rattled the TXV and may have damaged the internal components. Also, he didn't shield the TXV bulb from the heat while braising, potentially destroying the internals there as well.

    There was no nitrogen flowing while braising. I've done plenty of soldering on copper for water lines, but had never heard of using inert gas to purge oxygen from pipes. Now I'm sure there are flakes of crap inside the lines. I'm not sure how to clean that or even if I should.

    There were schrader valves on the liquid line that he just cut off and braised the pipe directly to the units. I'm not sure if that makes future servicing more difficult, or if it's ok to have them like that.

    There are two kinks in the liquid line. One where he bent it and another inside the coul itself where he tried to keep it from moving while hitting it with a hammer.

    The thermostat wire from the coil to the condenser outside is too short. I'll have to crawl through and pull another one. No big deal, just frustrating

    I will install the condensate pump. This will be a first for me, but it doesn't seem too hard. Just need to run 3/4" Schedule 40 in to the pump and 3/8" clear tubing out, up into the attic and outside. If I'm understanding this correctly, I'll need to run the tubing high enough into the attic to have positive slope from there to the other end, winding up on the ground outside.

    The coil is pre-charged with refrigerant. Hopefully it has the 10.8 lbs in it still as 410 is getting expensive.

    So, if you've read all this and know a bit more than the guy that "helped" me, just how F'd am I? I can't start oveer and invest another $5k into equipment.

    Roger

    '83 GS850G Daily rider
    '82 GS1100GK Work in (slow) progress

    #2
    Calling dorkburger , our resident HVAC guy. There may be others. But I would think that Glen might be able to offer some guidance. I have his email if you’d rather. Let me know.
    Rich
    1982 GS 750TZ
    2015 Triumph Tiger 1200

    BikeCliff's / Charging System Sorted / Posting Pics
    Destroy-Rebuild 750T/ Destroy-Rebuild part deux

    Comment


      #3
      Originally posted by Rich82GS750TZ View Post
      Calling dorkburger , our resident HVAC guy. There may be others. But I would think that Glen might be able to offer some guidance. I have his email if you’d rather. Let me know.
      He was my first thought as well. I thought I had his contact info, but can't find it. Let's see if he chimes in or gets an email notification for the PM i sent.
      Roger

      '83 GS850G Daily rider
      '82 GS1100GK Work in (slow) progress

      Comment


        #4
        I did a quick pressure test last night with nitrogen and only got up to 50psi before noticing leaks, unfortunately that was no surprise. The system max pressure is 500lbs. Also I pulled the cover off of the coil on top of the furnace, and saw the pinched line on the low side. That was the 3/8 line that got banged up and is also connected to the TXV. I'm reading that TXV is super delicate, so given that, and the sensing bulb which is likely cooked inside, I just ordered a new one. Don't want to risk destroying a brand new condenser.

        There is a new(ish) silver solder called Stay-Brite. It doesn't need to reach 1200 degrees to flow, so I won't need acetalyne, mapp gas will work. Keeping fittings cooler, I'll be less likely to cook something that shouldn't be. Another benefit to less heat is less, or no, build up of oxydization inside the lines. I plan on cutting out the nasty joints and reworking the lines. Also flushing the crud out that formed when the other guy heated the fittings till they glowed red.

        Lord willing, I'll have the pressure test done, vacuum and charge this system this weekend. (Not that anyone here cares though). I was fortunate to be able to borrow a nitrogen bottle, along with the hoses and gauges I'd need from a friend.
        Roger

        '83 GS850G Daily rider
        '82 GS1100GK Work in (slow) progress

        Comment


          #5
          All that’s left is to deal with DIL’s dad.
          Rich
          1982 GS 750TZ
          2015 Triumph Tiger 1200

          BikeCliff's / Charging System Sorted / Posting Pics
          Destroy-Rebuild 750T/ Destroy-Rebuild part deux

          Comment


            #6
            A study in why we work on our own bikes, cars, boats, etc., etc..., when able.

            I'd love to have a good 4-wheel (cage) mechanic. Don't know one, though I'm sure they're out there. Or maybe I'm not sure anymore (lol).

            Sounds like you know a whole lot about it already. I've been in the business for over 25 years, but I'm a heat guy, not refrigeration. I can name the parts and point to 'em, but that's about it.

            Can't say I'm familiar with Schrader valves on the liquid line...; But yeah, (ham-fist-induced) restrictions doesn't sound good. And leak-free is not an option.

            Just fix it and don't tell dude about it (lol). Can't give him a bad review since it's on the side (lol). Definitely sounds frustrating...

            Comment


              #7
              Hey Roger. Been dealing with some stuff over here. I just saw this a couple of hours ago.


              The kinks are a concern. Minor ones aren't the end of the world, but if they are kinked enough to restrict flow it's potentially a big problem.

              Cutting off the schader ports was just asinine on his part. To properly evacuate the system both the high side (small line) and low side (big line) need to be evacuated and both are needed for proper servicing / startup.

              Nitrogen purging is one of those "best practices" things and good to do. That said I've done it both ways. If the condenser has a filter drier it'll catch any scale, but if the filter gets plugged thats another restriction problem. I'd bet that the percentage of residential systems that got a nitrogen purge during hot work is in the single numbers. Multi head ductless splits are an exception with their intricate components and a different animal then what you're working on.

              The TXV. They can take some heat but I'll typically wrap a dripping wet rag around them while brazing. The mass of the TXV vs the pipe tends to make it a heat sink and sometimes its tough to get the connection hot enough to flow the braze before everything is blazing hot. I have been in difficult situations and have hit them with way more heat then I figured they'd survive but they lived. Some of them have nylon seats in them, some are all metal. Sounds like you're going with cheap insurance and replacing it anyway.

              Stay Brite should be ok, just make sure to get the appropriate flux (Stay Clean) and prep like a typical plumbing connection.

              If you have paperwork on the unit check to see if there is a lineset length chart to see if the factory charge is sufficient. If you can, it may be worthwhile to hoard some 410a. Its going away. I'm not as current on specifics as I should be, but I'm pretty sure that 410a units are no longer being manufactured. Refrigerant should be around for a while, but not forever, and the price will go up like R22 has.

              I'll keep an eye on this thread. If I missed anything or any other questions come up, let me know.
              sigpic
              When consulting the magic 8 ball for advice, one must first ask it "will your answers be accurate?"

              Glen
              -85 1150 es - Plus size supermodel.
              -Rusty old scooter.
              Other things I like to photograph.....instagram.com/gs_junkie
              https://www.instagram.com/glen_brenner/
              https://www.flickr.com/photos/152267...7713345317771/

              Comment


                #8
                Thanks for chiming in, dorkburger. Also JMHJ and Rich82GS750TZ . Indeed, this was another lesson in why we do our own work on things. I can't be so proud as to not accept help from anyone, being a bit more careful about who I use OTOH is the takeaway here. i am actually grateful for the other guy's "help". Without his offer, I likely would have waited even longer and spent the money we used on this system to take a week off, riding 3k miles to Indiana. My wife thanked me for this sacrifice. I figured it more of a priority than sacrifice, but that was nice of her. Maybe next year for that rally, but I digress.

                I got the system working! I learned that refrigeration copper is measured by OD, unlike water lines that use ID. It's no wonder some of the fittings didn't work. To get around mixing water and refigerant fittings, I bought a swage tool It anlso eliminated a few solder joints, which worked out beautifully. The new bends are exactly how I had envisioned them, no kinks and now are the proper length to have a clean install. The TXV wasn't hard to replace. I fastened the sensing bulb (which was nowhere near the flame this time) to the vapor line, as required, and wrapped it all up with insulating tape.

                Finding a vacuum gauge was challenging. The supply places refused to sell it to me since I don't have an EPA cert for refrigeration. That's rediculous, I thought. Finally got one and did a pressure test,after replacing the leaking fittings, and it held at 200 PSI for 24 hours. The next day I pulled a vacuum which only went down to 25k microns. Did a nitrogen purge and repeated that process four times before getting down to 300 microns. It held tight at 1,000 microns for an hour and stayed within manufacturers specs. Not perfect, according to what I've read, but good enough for me.

                A local metal roofing place bent some metal for me to use as a line set cover, which I'm pleased with. The condensate pump is working as intended too. Wiring in the thermostat was another learning experience. I kept the gas furnace for backup, as we'll use primarily the heat pump. We'll compare the cost of running the heat pump vs gas furnace and decide which too use.

                My soldering isn't beautiful, but it held! In all, we're very pleased with this system. It cost quite a bit less than hiring out. but the experience was worth it.

                Pics or it didn't happen, right? LOL















                Last edited by Burque73; 06-22-2025, 11:13 AM.
                Roger

                '83 GS850G Daily rider
                '82 GS1100GK Work in (slow) progress

                Comment


                  #9
                  Looking good, Thoughts of a new career ???
                  1983 GS1100E, 1983 CB1100F, 1991 GSX1100G, 1996 Kaw. ZL600 Eliminator, 1999 Bandit 1200S, 2005 Bandit 1200S, 2000 Kaw. ZRX 1100

                  Comment


                    #10
                    Nice. I'm glad you got it sorted out.
                    sigpic
                    When consulting the magic 8 ball for advice, one must first ask it "will your answers be accurate?"

                    Glen
                    -85 1150 es - Plus size supermodel.
                    -Rusty old scooter.
                    Other things I like to photograph.....instagram.com/gs_junkie
                    https://www.instagram.com/glen_brenner/
                    https://www.flickr.com/photos/152267...7713345317771/

                    Comment

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