Compressor Condensation

[ATC USN]

I have a Carrier 25HNB648 compressor the coolant return line is producing a lot of condensation on the order of several gallons a day, it looks like most of the condensation is being produced at night. The problem is my compressor sits on top of a wooden retaining wall.

The exterior lines to the unit were insulated by the installer, but the lines inside the cabinet are not insulated.

I first impression is that the lines inside the cabinet need to be wrapped, but then I read that the problem may be caused by either low airflow or over/under charging.

The Compressor was recently relocated (because of a neighbor’s complaint) it sweated in both locations. Before it just watered the grass but now it’s going to rot out the retaining wall.

I have a FE4ANB005 Fan Coil and an Infinity control the T-Stat is set for comfort blower is set to auto.

[second opinion]

Over charged or low load

[ATC USN]

I have a 2400 sqft tri level house, 2/3 brick and 1/3 siding, it has 3 doors and 24 windows, but no insulation in the exterior walls, on a hot day it runs constantly.
It replaced a 3 ton unit which could barely cool the house below 78.

[second opinion]

I have a 2400 sqft tri level house, 2/3 brick and 1/3 siding, it has 3 doors and 24 windows, but no insulation in the exterior walls, on a hot day it runs constantly.
It replaced a 3 ton unit which could barely cool the house below 78.

Do you have any service tickets with performance data on them. An undersized duct system would cause this issue. Jumping one ton without redoing the duct system to compensate for the additional air can and usually will lead to equipment failure.

[TwincamDave]

You need a professional to go out to your home and check it all out. Too many items can cause your unit to do what you are describing.

[ar_hvac_man]

Air flow through the condenser usually dries up the majority of the condensation from the suction line. It IS all to common for me to see compressors sweating like a whore in church. Overcharge, dirty evap/poor airflow. Have it checked by a pro.

[kdean1]

A wooden retaining wall? If this wall is outside, doesn't it get wet when it rains or snows? If it isn't treated lumber it is going to rot anyway.
Is the entire compressor sweating or just the point where the suction line enters? The latter is normal, the former is not.

[ATC USN]

No service tickets with performance data.

The suction lines are definitely sweating, but the compressor is wrapped in a blanket I cannot tell if it is sweating, there is water dripping out from what look likes rubber grommet with metal tangs, (maybe a compressor shock mount or blanket drain) under the cabinet.

The compressors and fan coil was installed in May 2012. I had the compressor relocated last week because the neighbor was complaining. It sweated in both locations.

There are 18 supplies and two returns a 14 X 14 first level and a 28 X 14 third level.
The fan coil is located in a crawl space under the second level.
The installer checked the duct work air capacity was 4500 CFM. I don’t remember the measurements but the supply and return duct work was larger than the fan coil the installer had to use reducers on both ends. The three ton unit was undersized it never shut off.

My T-Stat displays the static pressure it is .54 which is within limits.

The wall is made from landscaping timbers, even pressure treated lumber will rot if exposed to water 24/7 also the wall is under an eave and the gutters are drained into a ravine 40 feet away.

[drife678]

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[hvacvegas]

No service tickets with performance data.

The suction lines are definitely sweating, but the compressor is wrapped in a blanket I cannot tell if it is sweating, there is water dripping out from what look likes rubber grommet with metal tangs, (maybe a compressor shock mount or blanket drain) under the cabinet.

The compressors and fan coil was installed in May 2012. I had the compressor relocated last week because the neighbor was complaining. It sweated in both locations.

There are 18 supplies and two returns a 14 X 14 first level and a 28 X 14 third level.
The fan coil is located in a crawl space under the second level.
The installer checked the duct work air capacity was 4500 CFM.
You must have hit the 4 instead of a 1 there. It is rare to find a residential system out that handles 4500 cfm. Thats 11+ tons of cooling. Your returns diffenetly wouldn't handle that.


I don’t remember the measurements but the supply and return duct work was larger than the fan coil the installer had to use reducers on both ends. The three ton unit was undersized it never shut off.

My T-Stat displays the static pressure it is .54 which is within limits.

The wall is made from landscaping timbers, even pressure treated lumber will rot if exposed to water 24/7 also the wall is under an eave and the gutters are drained into a ravine 40 feet away.

Am I the only one here that thinks a condensating suction line is normal?
Inlet, lets say 72* return, could be as high as 43* saturated suction. TXV 10* superheat, suction temp 53. 53* is probably below the dew point in my area today. Now the line is sweating.

I've never heard of a suction line sweating gallons a day.
But, I'm just a installer.

[just_opinion]

The suction line WILL SWEAT if the OD air meets its dewpoint temp. Wonder how much does it cost to insulate the suction line within the unit ALL THE WAY to the compressor? I am sure this compressor has the blanket cover.

I don't think the unit is over-charged causes MORE SWEAT because the inside has TXV (hopefully it is properly installed).

[ar_hvac_man]

No doubt the suction line will sweat but your compressor shouldnt be pouring water. that was my point anyway

[hvacvegas]

The suction line WILL SWEAT if the OD air meets its dewpoint temp. Wonder how much does it cost to insulate the suction line within the unit ALL THE WAY to the compressor? I am sure this compressor has the blanket cover.

I don't think the unit is over-charged causes MORE SWEAT because the inside has TXV (hopefully it is properly installed).

I don't think the question is how much does it cost to insulate.
I think the question is why the heck does it matter.

Seriously though. Several gallons? A day?
At 4 gallons a day (if the unit runs literally 24 hours, which I doubt), your looking at about a quart every hour.

I am officially claiming:
"Pics or it didn't happen."
Or I should say video.

[jpsmith1cm]

Well, a gallon of water requires just over 8000 btus per hour to condense out of the air.

So, if we actually ARE condensing gallons a day, how much energy is being wasted.

[catmanacman]

Sounds like normal operation , if the unit has a accumiator it will condensate more

[ATC USN]

My installer came out today and checked the pressures and said it was ok.
He pointed out that it’s the accumulator that is what is producing most of the water. In an earlier I post pointed out rubber grommet with the metal tangs had water coming dripping out of it, turns out that’s the accumulator mount.
The only solution he could offer was a drip pan with a drain line to channel the water away from the house.
I placed a 2” roasting pan under the accumulator mount area at 0700 by 1000 it was full. I now have water leaking into the crawl space through the foundation wall, anybody who thinks that isn’t an issue should consider finding another line of work.

[ATC USN]

Well, a gallon of water requires just over 8000 btus per hour to condense out of the air.

So, if we actually ARE condensing gallons a day, how much energy is being wasted.

“As water vapor condenses back to a liquid or solid phase onto a surface, the latent energy absorbed during evaporation is released as sensible heat onto the surface.” I haven’t done the math, but I’m curious as to why the manufacture chose not insulate the accumulator.

[jdblack]

As others have mentioned the condensation is going to be a normal thing depending on where the dew point maybe at a given time. Your biggest concern is where the condensation is going. Have your contractor install a pan and modify it to control the drainage. It's an unfortunate side effect. We can talk about wasted btu's but reality is that it's just like the exhaust gasses in your car. There is wasted energy there as well and that's why someone had the bright idea to design and build turbochargers to put that wasted energy to work. Why not collect that water and use on your garden?

[jpsmith1cm]

“As water vapor condenses back to a liquid or solid phase onto a surface, the latent energy absorbed during evaporation is released as sensible heat onto the surface.” I haven’t done the math, but I’m curious as to why the manufacture chose not insulate the accumulator.

Because the purpose of an accumulator requires that it be able to absorb heat.

Insulating an accumulator is counter-productive

[jpsmith1cm]

As others have mentioned the condensation is going to be a normal thing depending on where the dew point maybe at a given time. Your biggest concern is where the condensation is going. Have your contractor install a pan and modify it to control the drainage. It's an unfortunate side effect. We can talk about wasted btu's but reality is that it's just like the exhaust gasses in your car. There is wasted energy there as well and that's why someone had the bright idea to design and build turbochargers to put that wasted energy to work. Why not collect that water and use on your garden?

Now we're thinking.