Central air conditionner remote location

[Bencrx91]

Just curious, I will have a central AC installed this spring.

I want to have the compressor (the outside box with fan) in a remote location that is about 12 ft from the home. This area is separated from the house by a sidewalk. Is there any way I can run the r410 lines under the sidewalk ?

The model I will install is a Trane XR13.

Thanks in advance!

 

[rickairmedic]

Ben first off steer clear of Trane they are not the cadilac they used to be they changed compressors back around 2000 and have not gotten the new one right yet . I have changed out more trane compressors than I care to think about in the last 10 years ( the changeover started in 1999 ) . My next question is are you planning this install or are you having a Pro put it in ? My next question is why you wish to have the new unit that far fro the house if it is for noise reduction you need to hear some of the newer units running they are extremely quiet compared to older units.


Rick

 

[Bencrx91]

Thanks for the answer Ric.

Actually, I just purchased the Trane furnace and A/C a few weeks ago
The installers will replace the furnace next week and install A/C around spring time. Good thing I got the 2 years p/l extra warranty !

The reason I want the A/C in a remote location, is that it will be hidden-away behind the garden shed on the side of the house. I have attached a picture of the setup. It's "in between" my house and the neighbor house.

Noise wise, I will have a patio and zen backyard, so I want to push the noise source away from the backyard as much as possible.

To what compare the new compressor noise ? A refrigerator ?
I never owned one, hard to tell, but the neighbor one is very noisy, and it's only 5 years old. :O)

Thanks again for your help.

Ben first off steer clear of Trane they are not the cadilac they used to be they changed compressors back around 2000 and have not gotten the new one right yet . I have changed out more trane compressors than I care to think about in the last 10 years ( the changeover started in 1999 ) . My next question is are you planning this install or are you having a Pro put it in ? My next question is why you wish to have the new unit that far fro the house if it is for noise reduction you need to hear some of the newer units running they are extremely quiet compared to older units.


Rick

 

[autoist]

I rn my lines underground from my porch to my outside unit - within 9 months I had burned up the compressor. Installed another compressor (under warranty) & burned it up within the year (another warranty exchange) but this time a different repairman moved my lines above ground & that compressor worked for 10 more years!

 

[rickairmedic]

I rn my lines underground from my porch to my outside unit - within 9 months I had burned up the compressor. Installed another compressor (under warranty) & burned it up within the year (another warranty exchange) but this time a different repairman moved my lines above ground & that compressor worked for 10 more years!

Ben Autoists answer is the exact reason I asked all the questions . The refrigerant will do funny things running underground which could mean returning back to a liquid from a gas before reaching the Condensor ( the box with the fan and compresor in it ) . Sending loquid refrigerant to the compressor is not a good thing as it pisses off the compressor when you ask it to compres a liquid . I would have really questioned your installers if they had actually done this for you. The way a central AC system or even a window AC unit for that matter works is the refrigerant leaves the condensor ( the outside box ) as a liquid through the smaller of the 2 copper tubes and goes to the Evaporator coil ( the box thata sits ontop of your furnace ) . As it runs through the evaporator air flowing acros the coil causes the refrigerant to turn from a liquid state to a gas this is part of what creates the cooling effect. Then it returns through the larger copper pipe to the Condensor ( the box outside ) runs through the compressor which provides the presure for it to keep running through the system. Then it runs through the condensor coils in the condensor which condenses it back into a liquid as it dissapates the heat it picked up in the house before starting the whole trip over again.

Rick

 

[redsky49]

Of course you can run refrigerant piping underground. It is done all the time. The risk is that refrigerant, which also lubricates the working parts of the compressor, can do funny things if the refrigerant piping is not installed or sloped properly. Perhaps Rickairmedic can also speak to that. Length of piping also comes into play, as do accidental piping "traps", etc. Most manufacturers can provide a long line 'kit' to assist in placing the outdoor unit further away than normal.

Rick, doesn't Trane use a lot of standard Copeland units in their condensing units? From my vantage point, I haven't seen a lot of difference in residential systems by Trane, Carrier and York, but then again, I don't install them. Biggest problems I've seen have come from inadequate airflow due to home owners/installers placing the condensing unit too close to an exterior wall and then surrounding the unit with shrubbery or fences, allowing leaves to foul the unit, etc.

If this is what the OP wants, select a good contractor and pray that the actual mechanic that installs the unit knows what he is doing. If all else fails, call Trane tech support and discuss your situation.

Offered only as opinion

 

[mmg440]

What happens in underground the low side/gas side is cooled to much before entering the compressor causing the liquid to get into and "slug it" hydro lock like a car engine with anti-freeze or gas in the cylinder. Very Very hard on it.

That said it can be done well anything can be done!! Refrigeration systems have to contend with this many time because of the colder temps they may be dealing with, What many commercial refrigeration systems do is a solenoid valve shuts the flow of refrigerant to the evaporator. the compressor will pump down the system and the shut of by a low pressure switch in the system. This work well because there is not enough refrigerant in the line set then to liquefy and cause a compressor slug. Another option is a low side residual pressure valve many times use on blast freezers. In most cases I would think running the high side(pressure small tube) in the same insulation as the low side for the last 10 feet or so should keep this to a minimum, or if at all possible after coming out of the ground on the condenser side have the low side line at least 5' un-insulated go to the condensing unit. This will allow the refrigerant in this part of the line to heat up and stay as a gas before entering the compressor and possibly slugging it.

What you are proposing is putting the unit were you want and out of your other area is really good. I am afraid most hvac contractors most likely would not get it right without some guidance. They just are not used to dealing with this type of condition. I think you may want to contact a contractor that also does commercial refrigeration to get a solid plan in the works and yes express your concerns up front. I only did commercial refrigeration for a short number of years and no longer am I involved and every install and service was different. Many times I was sent out to correct installs performed incorrectly for one reason or another.


"Offered only as opinion " mine too

 

[rickairmedic]

Ok here is one option that would allow you to do what you want but I wont say it wont void the warranty on the unit . Have the installers add an accumulator to your new condensor these are used in heat pumps mostly to insure liquid refrigerant doesnt get back to the compressor . This would be installed inside the condensor before the compressor . The idea here is that liquid refrigerant is stopped at the accumulator before it gets back to the compressor basically a canister with a long and short pipe stuck in the top liquid goes in on the long side but only gas coes out the shorter pipe.I have been in the business for 20 years and own an HVAC company and I would not do what you are wanting done most newer units are not much louder than a refrigerator and honestly some of the higher end units such as carrriers Infinty 18-21 seer units you cant hear running nless you are standing right on top of them. The first one of these I put in several years ago freaked me out becouse I came out the back door of the house 15 feet from the unit and didnt hear it running it wasnt till I got right next to it that I realised it was running and even then it wasnt loud.

Rick


Rick

 

[mmg440]

Neat to here about the new units being so quite. I could still see wanting to have a unit out of the way. If wanting to keep it as a conventional ac system he probably could also run say a 3" or 4" PVC under the walk so the lines would not be in contact with the ground?

Just a note if going with the designing a system with a accumulator as rick spoke of the system should ideally should be running a TXV and not cap tube or office for the restriction by the evaporator.

I had no idea system have gotten that quite. Maybe see if you can go see someone's new system running this summer and the decide were you might want to put it. You may save your self a lot of expense. Don't forget all A/C condenser units will still put out heat no matter how quite.

 

[rickairmedic]

MMG ost newer systems use TXV's in order to get the higher SEER ratings so that shouldnt be a proble . I had also thought of using PVC to run the lines in but this I think woud fill with water and become a problem.


Ben you might ask your dealer if the distributor has units at the warehouse set up and running so you could see what they sound like . My Locaal Carrier distributor has several differant systems set up and running at their warehouse so I can take customers over there for sound tests.


Rick

 

[Bencrx91]

WOW ! Thanks every one for the info, that's very valuable comment.

I will follow your guidelines and see if the sound of the unit is ok.
I could find some db on the specs of the trane XR13
http://www.waychoffsac.net/pdfs/ac-XR13.pdf = 75db

75db = dishwaser run in the open.
http://www.tlc-direct.co.uk/Technical/Sounds/Decibles.htm

Shouldn't be that bad ?

After talking to the company today (before I saw your posts), he mentioned that most likely they would not be able to honor the warranty if something happens, since it's not a common setup and distance is close to 30ft away from the furnace.

The last thing I want, is a A/C that fails too quickly, these gizmos are expensive.

Thanks again for help, much appreciated.

 

[Bencrx91]

Finally got the new furnace in this week in the basement.
Here is the old vs the new furnace.
AC components will be installed in spring time.
I have attached some pictures of the work.
Have a nice week end !
Ben

 

[rickairmedic]

Ben your installers seem a ittle off to me . I understand why they didnt want to set the condensor right now ( its really cold outside ) but why they didnt go ahead and set the Evap coil on the furnace makes no sense . They have basicaly doubled their work by not puting it on top of the furnace while all the flue pipes and such were out of their way .I will also point out that that evap coil should be inside an insulated cabinet not just tossed into the metal ductwork.

Rick

 

[Bencrx91]

Thanks Ric for the comments.

What do you mean when you say an insulated cabinet ?
Do you have an example / picture ?

Thanks,
Ben

Ben your installers seem a ittle off to me . I understand why they didnt want to set the condensor right now ( its really cold outside ) but why they didnt go ahead and set the Evap coil on the furnace makes no sense . They have basicaly doubled their work by not puting it on top of the furnace while all the flue pipes and such were out of their way .I will also point out that that evap coil should be inside an insulated cabinet not just tossed into the metal ductwork.

Rick

 

[rickairmedic]

Ben the cabinet would be the same color as the furnace on the outside and have insulation on the inside . Basically your guys are cheaping out which is odd cause cased coils really are not much more than uncased coils . The only time I install an uncased coil is in a Mobile home and thats the way they come factory.

Rick

 

[Bencrx91]

Thanks Ric, I have looked around, to my surprise , and it seems that it's a common thing in the area, all my neighbors are installed the same way. I just don't see how it will fit in my current setup, it seems that the coil will arrive right in the lower joint, I'll send more detailed picture tonight.
Thanks again,
Ben