Installation Question

[mamatrio]

I have quotes from 2 HVAC contractors in my area. Both are very reputable. One is our long time HVAC company for our home.

We have nearly 20 year old equipment in Texas.

Although we are planning on replacing both of our upstairs units sometime in the future, we wanted to change out the 4 ton downstairs unit now. During the conversations, I asked if we could relocate one of the condensers from one side of the house to the other, so all three would be together, in the shade.

Both contractors said they would be able to do this, but it would require having the tubing go on the outside of the house. I understand that. What got me is that one contractor said that we would need to change the tubing out all together, because the current tubing is too small. This contractor said that, in order for the unit to have the correct efficiency, that would need to be done. Our long time contractor said that, although it would affect SEER a little, by keeping the current copper line, the EER stays the same basically, and saves us a lot of money up front.

So, my questions to you are:

1. Does anyone have any strong thoughts (either way) about the benefit of moving the one unit to the shady side of the house - would it really make a significant difference?

2. What are your thoughts of having to change out the copper line tubing to the larger size?

Thanks in advance.

[beenthere]

The line set may need changed. To have close to the same capacity. Depends on how long of a run it becomes.
The EER won't stay the same. Since on a long line set run. You lose capacity. So the EER will be lower. Meaning it will cost more to use it. How much, depends on the line set length.

Connect a 5/8" 25 foot garden hose. Turn on the water to it and run it into a bucket. See how long it take to fill it.
Then take a 5/8" 100 foot long garden hose, and do the same. Does it fill the bucket as quick?

[Coolsville]

Mr. Beenthere is dead on the money here. Today's systems typically require larger lines. Reference the manufacturer's data for this. Length and vertical rise are your critical factors. While your "long time contractor" may be trying to save you a dollar, you may lose it in the long run. The new equipment needs everything one can provide it to get the most from it. Any compromise is going to effect the cost of operation and its lifespan. The longer it takes to fill that bucket costs you in more ways than one. Since new lines are needed anyway, I'd pay what it costs to put it in the shade. I've been all over Texas and it's hot everywhere!

[CynicX]

Improperly sized line set will make you lose efficiency. And will effect how long the unit last.

Its amazing to me there are still companies out there that would use an undersized line set. And this was is particularly funny, I can see reusing a line set if its inaccessible but to MOVE an incorrectly sized line THEN reuse it?! haha hilarious.

This also depends on the equipment but I dont think between manufactures and efficiency there is too much of a difference at the 4 ton level. You'll likely need 7/8" and 3/8"...

Good luck, you will pay for this thing one way or the other. Either up front to a quality company or in small increments to some hacks....

[sktn77a]

Ask to see the efficiency loss with a longer lineset length of your existing diameter. Depending on the added length, the losses are typically small (<3%) but this information is available in the specification sheets and installation instructions of most condensers, so check it out. Worst case scenario is you pay an extra $ for a new lineset. That's nothing on the cost of a new system.

[lancerbomb08]

i cant help but ask though...i noticed you were trying to replace the downstairs unit and they are saying the lineset is inaccedssable because its between the floors? so they want to run the copper on the outside of the house to the opposite side?? talk about a long run

[mamatrio]

I re-read my post and it is confusing, even to me.

In order to move the condenser, it would require a change in tubing.

Actually, the big downstairs unit is already on the shady side of the house. We would still have to place tubing outside (I guess), down the side of the house, if we enlarged the tubing. I guess I need to get the guy on the horn.

Also, what are ya'lls thoughts on horizontal vs. vertical airflow evaporators/furnaces?

[beenthere]

Horizontal VS Vertical makes no difference to the unit.
Its done for ease of installation, and room.

[wahoo]

If we have our "drutthers" we always try and use vertical (upflow) furnaces since most are manufactured primarily to operate in this position. Remember, heat rises, so if it has to go sideways, or down, then the basic operation must change somewhat. We seem to have a few more heat exchanger failures in our horizontal and downflow units compared to vertical (upflow) units. Heat "trapping" has to be one cause of increase, especially if operated with dirty air filters (which the homeowner never admits to).

[ga-hvac-tech]

Lineset (copper tubes) routed down the side of the house is common. Usually the contractor will place a gutter downspout pipe (or a specifically manufactured cover) over the lineset, it looks fine.

The other guys are right; the new equipment needs all the details to be right, or it does not work properly... which translates into more cost to heat/cool and shorter equipment life.

One of the reasons a wise person calls a pro to do this work is because the pro knows and understands the details.

[mamatrio]

One of the reasons a wise person calls a pro to do this work is because the pro knows and understands the details.

That is why I came on this board. I have 2 well respected professionals giving me conflicting information.

I really am not sure why our contractor feels that we don't need the larger diameter tubing. I have repeatedly told them that I'm not so much about saving money in the beginning, but would rather save time, money and hassle down the line. Again, I don't think he is trying to be dishonest. I'd bet that he just doesn't think it is really important.

[ga-hvac-tech]

That is why I came on this board. I have 2 well respected professionals giving me conflicting information.

I really am not sure why our contractor feels that we don't need the larger diameter tubing. I have repeatedly told them that I'm not so much about saving money in the beginning, but would rather save time, money and hassle down the line. Again, I don't think he is trying to be dishonest. I'd bet that he just doesn't think it is really important.

Before Jan of 2006, technical standards were a lot looser than they are today. When Uncle Sam bumped up minimum SEER to 13 (from 10), the equipment manufacturers responded with high tech stuff (that is sensitive to details). As we see 15, 16, 18, and even 21 SEER equipment; every detail has to be RIGHT, or problems happen.

While a slightly off lineset size may not be the end of the world; I woudl prefer a dealer/installer that is a perfectionist. Just my personal attitude (and the way I do things with my customers).

On the Lineset: Coming down from an attic, if the existing is 3/8 x 3/4, and the new equipment calls for 3/8 x 7/8 (all exterior diameter of copper tubing), that is not really a big deal... unless you have a major warranty issue and the factory sends out a rep that has a 'selfish' attitude... There is the issue of different oils due to different refrigerants, some dealers suggest new linesets to avoid contamination... there are flush kits that work well.

With the hi-tech equipment on the market, it is better IMO to follow the instructions to the letter... something many of us guys (not just HVAC, rather a male attitude... ) tend to not do...