# suction line insulation?



## coolmen (Apr 11, 2006)

Keeping the suction line insulated is very important.Not insulated WILL cause the line to sweat and drip water on the floor when operating. It will allso cause the air conditioner effiancy to drop.1/2 " thick insulation should be good.


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## Lookin (May 5, 2006)

If it is so important why don't the manufactures insulate the suction line inside the condensors.


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## coolmen (Apr 11, 2006)

Why on earth would you ask something like that on this site.ask the manufacter.I only do what is required of per manufacter INSTALL requirements.So lets insulate 12"to 15 "of sution line to the compresser and then insulate the compressor. The only real advantags I see is less noise from the compressor.


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## ASHMAD2BLUE (May 21, 2006)

I have a compressor that I think might still be good. I checked the ohms on it & I got 4.8 ohms on all three phases. Is this a good reading?


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## ASHMAD2BLUE (May 21, 2006)

Where is the best location to install an oil trap in a residential HVAC system


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## Chimichanga31 (Jun 2, 2008)

An oil trap on a residential? if you got a 3 story i can see it. Check with your manufacturer but usually if you have more than 20 feet of vertical rise you need to install one at the base of the riser and at the top. There is another problem if you are needing to install traps. If you got excessive run out of refrigerant pipe, you MUST upsize the lines. It is typically over 50 linear feet of travel, you MUST check with the manufacturer on that too. Don't take a SWAG at it. Internal friction of the gas along the wall of the pipe will seriously hinder performance. Don't believe me? Ask an MEP Engineer. Other wise if you have the lines running thru the slab then up a wall in a single or two story home, I wouldn't worry unless you have a long run.

The suction line also serves to cool your compressor. As the compressor compresses gas, it generates heat. Building codes in my area require a 1-1/2" wall insulation on suction lines. If I use a cellular type of insulation. I am required to paint it with white exterior grade paint where it exposed to weather. Goofy but it's what is required. Other than that it is simply to keep condensation from forming.

The suction line needs to be insulated to the point where it connects to the manifold on the evaporator. Any condensation past that will get caught by the pan or evaporated in the airstream.

ASHMAD, if you got 3 phase power in your home. You or the person who had the house built knows someone at the power company who hooked you up good. It is very rare to find 3 phase outside of commercial buildings. The data plate on your compressor or unit housing will tell you the amperage (not resistance) of your unit. And i will bet good money it is 240 volt/1 phase on the outside unit (same for the inside unit if you have electric heat. Gas heat will typically be 115 volt/1 phase to power the fan) Don't mistake that because you have two or three lines running to a unit that is a phase of power to each. I would explain it but i don't want to right another half a page about series and parallel circuits and how it effects voltage.

Not trying to come across as a know-it-all. Just answering your questions. Good luck


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## HvacWiz (Nov 24, 2006)

Chimichanga31 said:


> An oil trap on a residential? if you got a 3 story i can see it. Check with your manufacturer but usually if you have more than 20 feet of vertical rise you need to install one at the base of the riser and at the top. There is another problem if you are needing to install traps. If you got excessive run out of refrigerant pipe, you MUST upsize the lines. It is typically over 50 linear feet of travel, you MUST check with the manufacturer on that too. Don't take a SWAG at it. Internal friction of the gas along the wall of the pipe will seriously hinder performance. Don't believe me? Ask an MEP Engineer. Other wise if you have the lines running thru the slab then up a wall in a single or two story home, I wouldn't worry unless you have a long run.
> 
> The suction line also serves to cool your compressor. As the compressor compresses gas, it generates heat. Building codes in my area require a 1-1/2" wall insulation on suction lines. If I use a cellular type of insulation. I am required to paint it with white exterior grade paint where it exposed to weather. Goofy but it's what is required. Other than that it is simply to keep condensation from forming.
> 
> ...


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## Chimichanga31 (Jun 2, 2008)

I am sure he will not be the only person who will need to have that question answered. And since no one else ANSWERED it, I thought i would do it.

And yeah. I didn't bother to look at the date.:no:


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