Safe HVAC drain line cleaner?

[Cropduster172]

I had/have the same issue with my condensate pump drain line.
I put 2 of these in the condensate pump collection box about once per month especially in summer
Works great.


https://a.co/d/03YKSoQ3

 

[alarmguy]

Sorry if I did not make myself clear. These are not the overflow lines. These are the condensate lines inside the attic that drain to the plumbing system.

Good point.
Our two unit system had 4 drain lines outside the house. 2 for the evaporator units and 2 for the overflow. I would do the garden hose procedure on the unit lines. Also in the attic, the installers had a removable cap that if you wanted to you could put a capful of bleach in there. It would be feasible to also put a copper wire.
That home is now sold.

Our new home, one unit, has two lines outside the house. The one within one foot of the ground is the evaporator unit drain. If I trust the installer properly glued the PVC pipe I will do the same and force water up it with the garden hose. Method can be a little unnerving though it worked perfect on the last house.
If not I will go in the attic which is a hassle in this new home and check to see if they put a cap on the drain for copper or bleach. Most likely I will use bleach. Though its rough getting in the attic, builder did not supply a staircase. Thinking about having on installed.

Interestingly now on all new homes, at least here on the NC coast. The overflow pan pipe is located high off the ground near the soffit on one story homes and two story homes its way up there about the same level. Makes perfect sense because if water ever starts dripping from high up you will see it and know you have a clog in the unit drain line.

 

[BMWTurboDzl]

My BIL who sells commercial units told me to put a couple of pennies in the pan near where it drains. Seems to kill whatever was growing in mine.

Copper has been used to help keep ship bottoms free of barnacles for centuries. I never thought that pennies contained enough copper to the job in an HVAC line.

 

[QwikKota]

The tablets are supposed to be placed inside the evaporator unit's condensate collection pan, not inside the PVC drain line.

Mistakes were made.

 

[QwikKota]

Good point.
Our two unit system had 4 drain lines outside the house. 2 for the evaporator units and 2 for the overflow. I would do the garden hose procedure on the unit lines. Also in the attic, the installers had a removable cap that if you wanted to you could put a capful of bleach in there. It would be feasible to also put a copper wire.
That home is now sold.

Our new home, one unit, has two lines outside the house. The one within one foot of the ground is the evaporator unit drain. If I trust the installer properly glued the PVC pipe I will do the same and force water up it with the garden hose. Method can be a little unnerving though it worked perfect on the last house.
If not I will go in the attic which is a hassle in this new home and check to see if they put a cap on the drain for copper or bleach. Most likely I will use bleach. Though its rough getting in the attic, builder did not supply a staircase. Thinking about having on installed.

Interestingly now on all new homes, at least here on the NC coast. The overflow pan pipe is located high off the ground near the soffit on one story homes and two story homes its way up there about the same level. Makes perfect sense because if water ever starts dripping from high up you will see it and know you have a clog in the unit drain line.

Both of the units have a tee with a vertical vent to allow the air to escape and a ball valve. I am not sure what the valve is for but it must be required per code. If the valve was upstream of the tee it would make more sense. I am going to cut the pipe downstream of the valve and add a tee with a schrader valve connection to be able to pressurize the system to blow out the sludge. If it gets above 40 psi or so I will stop and use a snake.

The HVAC units are always in the attic in Houston as far as houses are built. The entire unit and ducting is soaked in 120 degree air during the summer, it's ridiculous. The pans all drain to the soffit, yes.

 

[alarmguy]

Both of the units have a tee with a vertical vent to allow the air to escape and a ball valve. I am not sure what the valve is for but it must be required per code. If the valve was upstream of the tee it would make more sense. I am going to cut the pipe downstream of the valve and add a tee with a schrader valve connection to be able to pressurize the system to blow out the sludge. If it gets above 40 psi or so I will stop and use a snake.

The HVAC units are always in the attic in Houston as far as houses are built. The entire unit and ducting is soaked in 120 degree air during the summer, it's ridiculous. The pans all drain to the soffit, yes.

Yes, I think most all new construction it’s put in the attic. I haven’t seen a house in 20 years in South Carolina or North Carolina where it was put any place else.
I have multiple remote thermometers outdoors, indoors and believe it in that one of them is in the attic. I believe our attic hits much the same as you last I remember a peak of 126°f last summer.

I always have on my mind what could be a simple solution to cool the attic better without putting holes in the roof or an electric fan that needs maintenance. But then again our utility bills are very reasonable. Off peak is less than eight cents a kilowatt hour., four hours on peak during the summer is 21 cents a kilowatt hour

 

[QwikKota]

Yes, I think most all new construction it’s put in the attic. I haven’t seen a house in 20 years in South Carolina or North Carolina where it was put any place else.
I have multiple remote thermometers outdoors, indoors and believe it in that one of them is in the attic. I believe our attic hits much the same as you last I remember a peak of 126°f last summer.

I always have on my mind what could be a simple solution to cool the attic better without putting holes in the roof or an electric fan that needs maintenance. But then again our utility bills are very reasonable. Off peak is less than eight cents a kilowatt hour., four hours on peak during the summer is 21 cents a kilowatt hour

I have been meaning to install some sort of active cooling but have been procrastinating. I have a furnace blower in my garage ducted to a roof vent and it makes quite a difference.

 

[Nukeman7]

Both of the units have a tee with a vertical vent to allow the air to escape and a ball valve. I am not sure what the valve is for but it must be required per code. If the valve was upstream of the tee it would make more sense. I am going to cut the pipe downstream of the valve and add a tee with a schrader valve connection to be able to pressurize the system to blow out the sludge. If it gets above 40 psi or so I will stop and use a snake.

I prefer to flush the line(s) out annually with positive pressure using a garden hose because my HVAC unit is easily accessible in the garage. However, with your units in the attic, I suggest using a Shop Vac on the discharge outlet to suck out the accumulated crud buildup. The HVAC professionals often use this technique with 100% success when the air handler unit is difficult to access.

 

[QwikKota]

I prefer to flush the line(s) out annually with positive pressure using a garden hose because my HVAC unit is easily accessible in the garage. However, with your units in the attic, I suggest using a Shop Vac on the discharge outlet to suck out the accumulated crud buildup. The HVAC professionals often use this technique with 100% success when the air handler unit is difficult to access.

I tried that after removing the flexible hose that connects to the sink trap but no dice. I had to take it off of the wall fitting last year and use a snake to break the clog loose. After I unclog it I will add a slime prevention product. It's probably some of those dang de-scale tablets I put in by mistake.

 

[alarmguy]

I have been meaning to install some sort of active cooling but have been procrastinating. I have a furnace blower in my garage ducted to a roof vent and it makes quite a difference.

View attachment 337436

Nice!
The good part about that furnace and air-conditioning blower motors are pretty much maintenance free and they will last a very long time.

I don’t feel the same way about the attic ventilators sold in home improvement stores. I had a house once that I had one installed, pretty heavy duty bought at Home Depot. It had oil ports as well, and I kept it well oiled. It lasted for a while, but not that long.

On new homes with ridge vents, I’m not sure even if you could find a reliable model how effective it will be as you might be pulling just as much air through the ridge events instead of the lower soffit vents

 

[QwikKota]

Nice!
The good part about that furnace and air-conditioning blower motors are pretty much maintenance free and they will last a very long time.

I don’t feel the same way about the attic ventilators sold in home improvement stores. I had a house once that I had one installed, pretty heavy duty bought at Home Depot. It had oil ports as well, and I kept it well oiled. It lasted for a while, but not that long.

On new homes with ridge vents, I’m not sure even if you could find a reliable model how effective it will be as you might be pulling just as much air through the ridge events instead of the lower soffit vents

The initial install was using one of the blowers from the A/C installed in 1998. It lasted for several years before the bearings froze. I replaced the motor about 3 years ago for around $85.

Same here. I installed a replacement vent fan in our old home and it didn't last very long at all. Waste of money.

This house has ridge vents and I had 3 round vents installed, doesn't seem to help. I can't feel any air flowing so I don't think it's short cycling between these two. The soffit vents are relatively clear of insulation as far as I can tell. That is where I was thinking of installing a fan to pull in outside air, down low.

 

[alarmguy]

The initial install was using one of the blowers from the A/C installed in 1998. It lasted for several years before the bearings froze. I replaced the motor about 3 years ago for around $85.

Same here. I installed a replacement vent fan in our old home and it didn't last very long at all. Waste of money.

This house has ridge vents and I had 3 round vents installed, doesn't seem to help. I can't feel any air flowing so I don't think it's short cycling between these two. The soffit vents are relatively clear of insulation as far as I can tell. That is where I was thinking of installing a fan to pull in outside air, down low.

Yes, that’s the problem with ridge vents.
As far out as this idea might seem in my mind if you could put a duct up to the roof, but the blower down low, you would think that would help.

Or what about pumping air in at the soffit level?
Meaning a blower air intake down low blowing into the attic you would think that would force more hot air out the top…. Hmmmm …

 

[QwikKota]

Yes, that’s the problem with ridge vents.
As far out as this idea might seem in my mind if you could put a duct up to the roof, but the blower down low, you would think that would help.

Or what about pumping air in at the soffit level?
Meaning a blower air intake down low blowing into the attic you would think that would force more hot air out the top…. Hmmmm …

That's what I meant, the fan would be ducted so that the suction was through the soffit vents. I have an inducer fan off the furnace with a nice sized flange shaped like a small oven tray that would work well but most likely I would need 4 of them to make a difference. It's very small.

 

[alarmguy]

That's what I meant, the fan would be ducted so that the suction was through the soffit vents. I have an inducer fan off the furnace with a nice sized flange shaped like a small oven tray that would work well but most likely I would need 4 of them to make a difference. It's very small.

I just saw a devices like this. However, they seem to use a huge amount of energy, but I only know of one that I saw at 500 Watts I haven’t looked too much into it yet.

There are a ton of these things on the market all different size duct lines
I did a search for something like attic, blowers, or fans with ducts

Below is a link to even more, there are so many and in so many price ranges. Don’t just look at the one in the link below scroll down to the bottom of the page.
https://www.amazon.com/VEVOR-Industrial-Ventilator-Extraction-Ventilation/dp/B0D9Q8HLVT/

Besides the link above, here is another brand

 

[alarmguy]

I prefer to flush the line(s) out annually with positive pressure using a garden hose because my HVAC unit is easily accessible in the garage. However, with your units in the attic, I suggest using a Shop Vac on the discharge outlet to suck out the accumulated crud buildup. The HVAC professionals often use this technique with 100% success when the air handler unit is difficult to access.

Yes, I made a post in here. I’ve done this for 16 years on our old house.
I will admit, though, until I was sure I used to keep my fingers crossed that the contractor glued the PVC piping together and not just squeeze it in together.
Meaning reverse flushing it with the water pressure I was hoping somewhere along the line the pipe wasn’t going to disconnect in the attic

So now in the new home again, I’m wondering the same thingLOL HOPING THE CONTRACTOR PROPERLY GLUED ALL THE PVC PIPING

 

[JimPghPA]

My BIL who sells commercial units told me to put a couple of pennies in the pan near where it drains. Seems to kill whatever was growing in mine.

Copper in pennies might help, but do not let them touch the a aluminum of the ac evaporator or heater core. Try to distance them from those items.

While evaporator may be made of copper pipe and aluminum fins, when used in combination like that, it is without moisture getting between them.

Copper and aluminum are on opposite ends of the chemical electronegativity chart. So add moisture between them and you get corrosion. It will shorten the life of the evaporator and or heatercore.

 

[QwikKota]

I just saw a devices like this. However, they seem to use a huge amount of energy, but I only know of one that I saw at 500 Watts I haven’t looked too much into it yet.

There are a ton of these things on the market all different size duct lines
I did a search for something like attic, blowers, or fans with ducts


Below is a link to even more, there are so many and in so many price ranges. Don’t just look at the one in the link below scroll down to the bottom of the page.
https://www.amazon.com/VEVOR-Industrial-Ventilator-Extraction-Ventilation/dp/B0D9Q8HLVT/

Besides the link above, here is another brand

Thanks a lot. Those large ones look like beasts. I have used those for confined space work but probably a little overkill or expensive to run as you mentioned for attic venting. The flat gable style fan with louvers would be nice but I don't have a spot for one. The inducer fan I have is tiny in comparison.

 

[QwikKota]

Copper in pennies might help, but do not let them touch the a aluminum of the ac evaporator or heater core. Try to distance them from those items.

While evaporator may be made of copper pipe and aluminum fins, when used in combination like that, it is without moisture getting between them.

Copper and aluminum are on opposite ends of the chemical electronegativity chart. So add moisture between them and you get corrosion. It will shorten the life of the evaporator and or heatercore.

I would not say they are on opposite ends of the chart but definitely not ideal. I would be very surprised if aluminum is not extensively used in evap coils that have copper tubing. The fins darn near have to be made of aluminum. There is probably some sort of coating involved to prevent corrosion.

 

[JimPghPA]

I would not say they are on opposite ends of the chart but definitely not ideal. I would be very surprised if aluminum is not extensively used in evap coils that have copper tubing. The fins darn near have to be made of aluminum. There is probably some sort of coating involved to prevent corrosion.

View attachment 337522

In my 2nd Colledge chemistry, course section on metals interacting, the handout the elderly chemistry teacher with industrial experience handed out, had one at the top of the list of electrochemical positivitely or negativity, and the other at the bottom of that list, making them have the biggest spread of electronegativity between any two metals on that list.

I still rember the two stories she told about copper and aluminum. A roofer installing copper gutters and downpipe saved a few pennies by making the gutter supports also of the copper he was working with, and using the aluminum roofing nails he had to tack them to the roof.

Throw in some rain for moisture and in a few years those gutters fell down from the corrosion where the aluminum nails interacted with the copper causing corrosion.

The other one was of a job she once was called for, an expensive aluminum injection mold had coolint leak problems when the copper pipe fittings corroded the area they were threaded into the mold, and the corrosion was so bad the mold could not be salvaged.

---‐------

I know its common to use copper pipes with aluminum fins in heatexchangees. They likley use something to slow the reaction between those metals.

 

[QwikKota]

In my 2nd Colledge chemistry, course section on metals interacting, the handout the elderly chemistry teacher with industrial experience handed out, had one at the top of the list of electrochemical positivitely or negativity, and the other at the bottom of that list, making them have the biggest spread of electronegativity between any two metals on that list.

I still rember the two stories she told about copper and aluminum. A roofer installing copper gutters and downpipe saved a few pennies by making the gutter supports also of the copper he was working with, and using the aluminum roofing nails he had to tack them to the roof.

Throw in some rain for moisture and in a few years those gutters fell down from the corrosion where the aluminum nails interacted with the copper causing corrosion.

The other one was of a job she once was called for, an expensive aluminum injection mold had coolint leak problems when the copper pipe fittings corroded the area they were threaded into the mold, and the corrosion was so bad the mold could not be salvaged.

---‐------

I know its common to use copper pipes with aluminum fins in heatexchangees. They likley use something to slow the reaction between those metals.

The galvanic chart I use at work has them about 1/3 of the chart apart. Opposite aluminum is stainless, not copper. They are both negative but not close enough together to be recommended in a mated fashion.