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Jon mackay
04-09-2010, 11:08 AM
Are condensate lines allowed to discharge to the exterior like this? (upper discharge line).
Wouldn't freezing be a problem with this?

Also the A/C discharges to the exterior. Any issues with that?

Rick Cantrell
04-09-2010, 11:28 AM
"Are condensate lines allowed to discharge to the exterior like this? (upper discharge line)."
Yes

"Wouldn't freezing be a problem with this?"
The A/C is not in use during freezing weather


"Also the A/C discharges to the exterior. Any issues with that?"
No

From the 2006 IRC

M1411.3 Condensate disposal. Condensate from all cooling
coils or evaporators shall be conveyed from the drain pan outlet
to an approved place of disposal. Condensate shall not discharge
into a street, alley or other areas where it would cause a
nuisance.

M1411.3.1 Auxiliary and secondary drain systems. In
addition to the requirements of Section M1411.3, a secondary
drain or auxiliary drain pan shall be required for each
cooling or evaporator coil where damage to any building
components will occur as a result of overflow from the
equipment drain pan or stoppage in the condensate drain
piping. Such piping shall maintain a minimum horizontal
slope in the direction of discharge of not less than 1/8 unit
vertical in 12 units horizontal (1-percent slope). Drain piping
shall be a minimum of 3/4-inch (19 mm) nominal pipe
size. One of the following methods shall be used:
1. An auxiliary drain pan with a separate drain shall be
installed under the coils on which condensation will
occur. The auxiliary pan drain shall discharge to a
conspicuous point of disposal to alert occupants in the
event of a stoppage of the primary drain. The pan shall
have a minimum depth of 1.5 inches (38 mm), shall
not be less than 3 inches (76 mm) larger than the unit
or the coil dimensions in width and length and shall be
constructed of corrosion-resistant material. Metallic
pans shall have a minimum thickness of not less than
0.0276-inch (0.7 mm) galvanized sheet metal. Nonmetallic
pans shall have a minimum thickness of not
less than 0.0625 inch (1.6 mm).
2. A separate overflow drain line shall be connected to
the drain pan provided with the equipment. This overflow
drain shall discharge to a conspicuous point of
disposal to alert occupants in the event of a stoppage
of the primary drain. The overflow drain line shall
connect to the drain pan at a higher level than the primary
drain connection.
3. An auxiliary drain pan without a separate drain line
shall be installed under the coils on which condensate
will occur. This pan shall be equipped with a water
level detection device conforming to UL 508 that will
shut off the equipment served prior to overflow of the
pan. The auxiliary drain pan shall be constructed in
accordance with Item 1 of this section.
4. A water level detection device conforming to UL 508
shall be provided that will shut off the equipment
served in the event that the primary drain is blocked.
The device shall be installed in the primary drain line,
the overflow drain line or the equipment-supplied
drain pan, located at a point higher than the primary
drain line connection and below the overflow rim of
such pan.

Jon mackay
04-09-2010, 11:40 AM
Sorry I didn't specify, the upper condensate is from a furnace which is why the concern for freezing.

Rick Cantrell
04-09-2010, 12:05 PM
M1411.4 Auxiliary drain pan. Category IV condensing
appliances shall have an auxiliary drain pan where damage to
any building component will occur as a result of stoppage in the
condensate drainage system. These pans shall be installed in
accordance with the applicable provisions of Section M1411.3.

Exception: Fuel-fired appliances that automatically shut
down operation in the event of a stoppage in the condensate
drainage system.

Refers you back to 1411.3

mike huntzinger
04-09-2010, 12:13 PM
make a note to see if water drips back on the house, protect from freeze,

H.G. Watson, Sr.
04-10-2010, 06:49 AM
Are condensate lines allowed to discharge to the exterior like this? (upper discharge line).
Wouldn't freezing be a problem with this?

Also the A/C discharges to the exterior. Any issues with that?



Sorry I didn't specify, the upper condensate is from a furnace which is why the concern for freezing.

http://www.inspectionnews.net/home_inspection/attachments/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/17225d1270836452-condensate-c-drain-exterior-100_3576-p.jpg


As I read the thread the upper discharge pictured is supposedly corrosive condensate from a condensing fuel fired appliance (vent), which I doubt. This discharge has no bend, is clear flex humidifier pan drain hose, not corrosive resistant, not UV resistant, and seems way too small to be such, and will discharge (as pictured) upon the drip loop/electrical cable for the AC from its shut off. That (corrosive condensate should that actually be the case, upon the cable) would not be good.

The portal would/could also be a point of entry for insects, snakes, and vermin.

I am doubtful that this line is condensate from a furnace, but more likely discharge from a humidifier catch pan below an evaporator pad, if in fact its origins are near the air handler, furnace, or return plenum. The clear flexible drain hose pictured also makes this much more likely, not designed for penetration to wall - or use outdoors (no UV resistance), should be indirect drain within home protecting water source (see NYS plumbing codes for proper materials and methods of drainage for humidifier pan drains).

Does NYS utilize the plumbing & mechanical chapters of the 2006 IRC? I didn't think so, but I'm not inclined to verify what NYS is presently using this morning.

imported_John Smith
04-10-2010, 08:19 AM
Since your in NY, Im making the assumption that the house has a basement. Any evidence of leakage or cracking adjacent to this area?

In my part of the country (gulf coast TX), where we have a lot of post tensioned slab foundations, I have seen MAJOR foundation issues from condensate draining to the ground like show in your photos.

Jon mackay
04-10-2010, 08:52 AM
http://www.inspectionnews.net/home_inspection/attachments/heating-ventilation-air-conditioning-hvac-home-inspection-commercial-inspection/17225d1270836452-condensate-c-drain-exterior-100_3576-p.jpg


As I read the thread the upper discharge pictured is supposedly corrosive condensate from a condensing fuel fired appliance (vent), which I doubt. This discharge has no bend, is clear flex humidifier pan drain hose, not corrosive resistant, not UV resistant, and seems way too small to be such, and will discharge (as pictured) upon the drip loop/electrical cable for the AC from its shut off. That (corrosive condensate should that actually be the case, upon the cable) would not be good.

The portal would/could also be a point of entry for insects, snakes, and vermin.

I am doubtful that this line is condensate from a furnace, but more likely discharge from a humidifier catch pan below an evaporator pad, if in fact its origins are near the air handler, furnace, or return plenum. The clear flexible drain hose pictured also makes this much more likely, not designed for penetration to wall - or use outdoors (no UV resistance), should be indirect drain within home protecting water source (see NYS plumbing codes for proper materials and methods of drainage for humidifier pan drains).

H.G. Thank you for the info.

This is a discharge from a high efficiency furnace. The furnace drains into a condensate pump which then routes to the exterior through the upper drain line pictured.

Jon mackay
04-10-2010, 08:55 AM
Since your in NY, Im making the assumption that the house has a basement. Any evidence of leakage or cracking adjacent to this area?

In my part of the country (gulf coast TX), where we have a lot of post tensioned slab foundations, I have seen MAJOR foundation issues from condensate draining to the ground like show in your photos.

No basement on this one. That area of the crawl was not accessible but I did not see any deterioration at the exterior.

I recommended routing the line to the laundry stand pipe.

Don Burbach
04-10-2010, 12:14 PM
I don't think anyone else has mentioned this, but it looks like the base of the condensor may be sitting in a depression/hole that will catch water, either from rain or from the condensation lines. This will shorten the life of the condensor.

Bradley Gleaton
07-07-2010, 11:06 AM
I live in Dallas, TX and my condensation line is sweating causing the wood to rot around it. The condensation line runs from the attic through a closet straight down into the crawl space and then it runs outside and dumps into our french drain. Now, the wood in the closet where the PVC pipe goes through is rotting b/c it has been sweating. What do you suggest I do to fix this? I thought about taking a drill bit and drilling the wood around the PVC pipe to make room to wrap the pipe with insulation, but I was not sure if that would do the trick or not. Please let me know what you think.


Thanks,

Bradley Gleaton

Michael Thomas
07-08-2010, 08:37 PM
(Borrowing thread for a moment...)

"Indirect receptor"... with easy clean-out.

Jim Luttrall
07-08-2010, 09:34 PM
I live in Dallas, TX and my condensation line is sweating causing the wood to rot around it. The condensation line runs from the attic through a closet straight down into the crawl space and then it runs outside and dumps into our french drain. Now, the wood in the closet where the PVC pipe goes through is rotting b/c it has been sweating. What do you suggest I do to fix this? I thought about taking a drill bit and drilling the wood around the PVC pipe to make room to wrap the pipe with insulation, but I was not sure if that would do the trick or not. Please let me know what you think.


Thanks,

Bradley Gleaton
Insulate the pipe.

Rich Goeken
07-09-2010, 05:02 AM
(Borrowing thread for a moment...)

(PHOTOS)

"Indirect receptor"... with easy clean-out.



Looks like the "drip pan" for the "Indirect receptor" meets the spec. min. of 1.6 mm thickness. :D

DANIEL SNYDER
07-09-2010, 09:18 AM
The amount of condensate from a HE furnace is typically low, possibly a few cups a day. It could freeze is very cold weather, so it would be best to run the condensate to an interior drain.

The other common problem with condensate systems is an inappropriate discharge point. There should be an air gap so that nasty sewer gases cannot be drawn back into the system. For example, condensate systems should not discharge into a plumbing stack.

The condensate is also corrosive, but is more corrosive when indoor air is used for combustion.

Does the unit have an air intake and exhaust for the combustion?

Ken Bates
07-09-2010, 10:57 AM
I've been discharging my furnace condensate into a reliabel old toilet tank (3+gallons) for more than 7 years. No problems.

The seasoned installer had it going out at the sill and created a vertical loop in the plastic hose on the bsmt side of the sill. The idea being, it would drain the water at the end and not leave any to be exposed to freezing and blocking the line. But I decided on not having any acid water impacting my plants.

I recall a brutally cold winter where I found a situation similar to that in the photo. The condensate had frozen around and up and on and in the small ac condenser. It was practically entombed. I informed my smug yuppie clients and then returned to finish up the exterior inspection.

The idiots impetuosly decided to "test" the condenser to see if was functional
but fortunately I have a habit of killing power to ac units when left on during the fall and winter.

DANIEL SNYDER
07-09-2010, 11:10 AM
The idiots impetuosly decided to "test" the condenser to see if was functional
but fortunately I have a habit of killing power to ac units when left on during the fall and winter.

You should check to see if the condenser has a crankcase heater before shutting it off ofr the winter.

The crankcase heater keeps liquid refrigerant from pooling in the crankcase and diluting the oil. It can be shut off during the winter but it needs to be on for at least eight hours before operating the unit the next spring or summer.

Most crankcase heaters consume around 50W. If you turn off the heater for 5,000 hours per year, that saves 250 kWh. At 10 cents per kWh, that is $25/yr. But if you forget to energize the heater in the spring, and damage the compressor, that could cost $750 to $1000.

I hope if you shut off the power you at least stop by in the spring to turn it back on before the yuppie homeowner runs their AC.

Rich Goeken
07-10-2010, 05:12 AM
You should check to see if the condenser has a crankcase heater before shutting it off ofr the winter.

The crankcase heater keeps liquid refrigerant from pooling in the crankcase and diluting the oil. It can be shut off during the winter but it needs to be on for at least eight hours before operating the unit the next spring or summer.

Most crankcase heaters consume around 50W. If you turn off the heater for 5,000 hours per year, that saves 250 kWh. At 10 cents per kWh, that is $25/yr. But if you forget to energize the heater in the spring, and damage the compressor, that could cost $750 to $1000.

I hope if you shut off the power you at least stop by in the spring to turn it back on before the yuppie homeowner runs their AC.


The reason for the heater is to make the AC an "All-Season" unit. This is required in some commercial situations where the AC unit will run 24-7 365 days, due the requirement to keep a room cool-----such as a communications room. Special order. Although I can't think of a situation where a home may have requirements such as these, they may exist. The condensate drain is routed to an inside floor drain, etc.

David Bell
07-10-2010, 05:36 AM
Most residential split systems have no crankcase heaters and don't need them. If it is warm enough to need A/C in your home then, migration of refrigerant is a non issue. Heat pumps and commercial units on the other hand should always have heaters along with other low ambient controls.

Tim Fuller
07-10-2010, 06:39 AM
I have a similar set up for condensation drains on my own residence that has a high efficiency furnace. I have not seen this on an inspection yet but I do have a couple of questions.

On a cold winter the condensate from the furnace forms a huge ice dam below the drain. The ice dam on mine looked like a stalagmite that was two feet high and had a base three foot across. If this happens in New York then a similar ice dam will be right on top of and encasing this electrical line. Wouldn't that be a concern?

In the summer my condensate drain will collect 20 gallons of water per day if I don't set the thermostat any lower than 76 degrees. That leaves a huge mud puddle under the drain. In the case of the picture in question wouldn't that undermine the pad that the AC unit is sitting on and cause it to tilt toward the house?

I have attached a pic of my residence for reference. My neighbor is only six feet away and if you combine the two AC drains flow then you can imagine how large the mud puddle can get.

David Bell
07-10-2010, 07:11 AM
Consider purchasing a condensate pump and piping it to an indirect drain, such as a washing machine drain.

Vern Heiler
07-10-2010, 09:29 AM
Consider purchasing a condensate pump and piping it to an indirect drain, such as a washing machine drain.


Some areas prohibit using the sewer for condensate drain, so draining to the exterior is the only option. As Tim said in the previous post, 20 gallons of condensate a day X thousands of evaporators = a lot of water to process.

James Duffin
07-10-2010, 10:24 AM
In NC where it gets cold but not "that" cold I normally recommend that a plastic hose that is used from a condensate pump be changed to 3/4" PVC before it goes outside and be piped away from the foundation just like an A/C condensate drain would be. Notice I said recommend since I have no code to back it up. But if there is a problem at least I tried. Piping to the sewer is not an option around here.

David Bell
07-10-2010, 04:15 PM
If 20 gals. a day is the norm I would consider a enclosed sump pit pumping to a drywell away from the house. The piping can be run below the frost line to prevent winter freezing.

Rich Goeken
07-10-2010, 08:42 PM
Consider purchasing a condensate pump and piping it to an indirect drain, such as a washing machine drain.


While this is an easy fix, it requires constant supervision. I have seen these units fail causing structural damage. Spec'ed them out in all communications rooms where I worked. A gravity drain should be 1st choice.

Tim Fuller
07-11-2010, 04:20 AM
I don't believe that the local authority would see the humor if I ran the condensate into the drains. Although this would be a wonderfully easy fix since the air handler is in the attic.

Our HOA won't let me dig a hole either. I think that we just have lots of water for our house plants in the summer.