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  1. #1
    Join Date
    Feb 2008
    Posts
    11

    Need Advice on Refrigerant Line Diameter on install that was just done!

    Hi,

    I need some advice on the refrigerant line size on our install. Here is the story....We had a 3 ton heatpump unit and after a few months we discovered that it was not producing enough and installer agreed to just swap it for a 4 ton and pay a little difference. This was all done and the new heatpump is working now. My concern is that with the 3 ton, 7/8 lines were needed. for the 4 ton, Goodman, recommends 7/8 up to 24 feet and 1 1/8" from 25-50. We have 30feet of line in all. The installer assured me that he spoke to Goodman and they told him that were ok with 7/8 as we were only a few feet over.

    I need your opinions on this guys. Would you guys replace them? I don't want to have issues in a couple years. If it is ok though, I don;t want to spend the extra $$ and time in fixing something that will not cause any problems.

    what problems or energy loss can this cause, if any?

    Thanks

  2. #2
    Join Date
    Feb 2008
    Posts
    11
    The installer came over today and spet an hour or more cheking over everything and taing readings to show me. He measured the outside temp on the big pipe and it was 120-130F. the pressure was at 175-180 at 35F outdoor temperature. He brought me a chart and it showed that what it should be at that outdoor temperature. The expanded heating chart stated that MBh should be 20.7 but we had 28-32...he said more is better. Its lower we do not want.

    Does this all sound right and make sense? The system uses r-22
    Temp at the inside vents are 95-100F

  3. #3

    contact Goodman

    Consumer Affairs Address
    7401 Security Way
    Houston, TX 77040

    To speak with a Heating and Air Conditioning Consumer Affairs Representative from within the United States, please call 1-877-254-4729.

  4. #4
    Join Date
    Feb 2008
    Posts
    11
    i called them and guess what they said....we only deal with installer. You'll need to conatc him for help

  5. #5
    Join Date
    Apr 2004
    Location
    Palmdale, CA
    Posts
    199
    The 7/8" lineset should be good for your 4 ton at 30'. I don't know why you would want to call consumer affairs.

  6. #6
    Join Date
    Apr 2004
    Location
    Palmdale, CA
    Posts
    199
    That is correct like I said I don't know why you would want to call consumer affairs, or why this guy would give you the phone number to call them. Just my opinion that this would be fine but if you doubt it you can have somebody not the same company come double check everything for the price of a service call. You can then have the peace of mind you want.

  7. #7
    Join Date
    Jan 2008
    Posts
    2,060
    I don't think an extra 6' of line beyond what's recomended can make a big difference. Maybe a very small reduction in efficiency rating. I'm sure others will have differing opinions.

  8. #8
    Join Date
    Jul 2004
    Location
    Massachusetts
    Posts
    6,837
    First, it sounds to me like you're not dealing with an exceptionally thorough company, though they do get points for replacing the unit with a larger one. At least they're trying. The problem is, they apparently never did a load analysis on the house or they would have known what the correct size HP is that you need and not have to guess at which size. So like many thousands of other HO's to this site, it all starts with a Manual 'J' load calculaton. After the p roper load is found, then a Manual 'D' duct inspection needs to be done. Actually, an inspection to compare a Manual 'D' duct system to what you have. You see, if the system was designed for 3-tons, then a 4-tons is squeezing to much air into the trunk. If it was designed for 4-tons, then clearly the 3-ton system was too small. So for the sake of discussion, let's assume the trunk system would ideally support a 3.5-ton system. You're a little over with a 4-ton but I doubt you'll truly see the difference. But if the home only nees 3.5-tons, then you've got about 12.5% extra capacity. Now if we follow your suggestion that the suction line should be 1-1/8 inches, ID, and it's only 7/8-inches ID, then we'll have a compressor that can't breathe as well as it would like. But it will breathe. The end result is you'll probably lose 1%-2% of capacity. So again, assuming you need 3.5-ton (42,000 Btu's/hr), you've got 4-tons (48,000 Btu's/hr) and lose even 3%, you've still got 46,560 Btu's available for a 42,000 Btu load. So I'd say forget the issue. The company may not have done a load analysis but they've paid for that dearly by having to swap out the unit for a bigger one. BTB, you never said whether they changed the indoor unit or just the outdoor unit. Anyway, just the fact that they came back and replaced with a bigger unit (hopefully at no cost to you), they're at least trying to do the right thing. I wouldn't try to squeeze too hard or you may end up against a stone wall.
    If YOU want change, YOU have to first change.

    If you are waiting for the 'other guy' to change first, just remember, you're the 'other guy's' other guy. To continue to expect real change when you keep acting the same way as always, is folly. Won't happen. Real change will only happen when a majority of the people change the way they vote!

  9. #9
    Join Date
    Feb 2008
    Posts
    11
    i am pretty happy with the service. I can;t really complain. He came back today, checked everything over brought me the technical data and we compared the readings together. I just want to make sure it didn't cause issues in the future if I left it like that. Who knows if these guys will be in business in a couple years.

    He offered to change it if it was necessary and would only charge me the price of the lines, but again its a hassle to change it all if it makes no difference. I will be finishing my basement in march, so just wanted to make sure before I started plastering/painting and all.

    The indoor unit is a new 4 ton goodman also.

  10. #10
    Join Date
    Feb 2007
    Location
    18951
    Posts
    1,593
    Some manufacturers will give a chart with a "capacity multiplier" when going to a lower tubing size. Having said that, I wouldn't worry about 6'. You have to know when to pick your battles, and this is not one of them. If you have a contractor you like, don't piss him off, you'll be the ultimate loser.

  11. #11
    Join Date
    Feb 2008
    Posts
    11
    sorry guys...i am at 34' not 30' it was a typo on my part.
    i hope this does not make a difference.

    As for the setup, we have it setup on a Honeywell VisionPro 8000 as a 3 stage heat....1st stage is heatpump, 2nd stage is heatpump and 10KWh (5KWh + 5KWh on timer) and 3rd Stage is full 20KWh. There is no heatpump cutout at 10F as he says he believes in leaving the heatpump work as much as possible for energy saving. What do you guys think about this?

    One last thing I just noticed a few mins ago, is that the heatpump is located on a wall mount on the outside wall of our TV room. We notice it makes a humming/vibrating sound, more than the 3 ton. Anything you guys can recommend trying to reduce the noise/vibration beside taking it off the wall mount and using a mount on the ground?

    Thanks!

  12. #12
    Join Date
    Jan 2004
    Location
    Lancaster PA
    Posts
    68,336
    You might have a 3% loss. Not a major loss.

    I doubt that your are getting more heat then the chart says you should.
    More likely, an incorrect measurement.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  13. #13
    Join Date
    Jun 2007
    Location
    Round Rock
    Posts
    3,586
    You'll be fine. Goodman is just CYA. They all do. We have run some long linesets on some jobs. Never had a problem, if you have stupid length of lineset, you need to make sure the unit has an accumlulator. Most do now. 30 ft. isn't even close.

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