Checking around doors for positive and negative airflow with a Smoke Pencil

Checking around doors for positive and negative airflow with a Smoke Pencil

How to check for positive or negative air flow around doors with a Smoke Pencil?

There are many hospitals that use the Smoke Pencil to check for positive or negative airflow around doors and ventilation registers to ensure that certain rooms in the hospital are not leaking air into other rooms.

Currently we are in the midst of a Corona Virus (COVID-19) outbreak in the United States. Hospitals are working feverishly to ensure their clean rooms, operating rooms, labs, quarantine rooms, waiting rooms, etc… are all separated effectively. This means the air in one room is not exchanging with the air in adjoining rooms.

Hospital maintenance staff often use the Smoke Pencil to check the airflow around door seals and vents to make sure the airflow is going in the correct direction and ventilation is operating properly. One advantage to using the Smoke Pencil is its vapor is a simple food grade mixture of Glycerin, Propylene Glycol, and water. This is much cleaner than using a smoke emitter to check airflow.

Why do I get smoke in my basement through the fireplace when I use the upstairs fireplace?

Why do I get smoke in my basement through the fireplace when I use the upstairs fireplace?

Q: Jason, I have 2 fireplaces, one below the other. There are 2 flues up the same chimney. The one in the basement has no damper and needs some work before it can be used, so we put a piece of concrete board over it and a bookcase to hold it in place to block the opening. Obviously, it wasn’t a perfect seal, but it was pretty covered.

We noticed though that when we used the upstairs fireplace smoke would come into the basement room. We want to use the upstairs fireplace this winter but aren’t ready to make a full decision on what to do with the basement fireplace. Would the Chimney Balloon be a good stop-gap solution until we decide whether to just block this fireplace off permanently or fix it? – MB

A: Dear MB, What you are referring to is called “smoke crossover” it happens when you have two chimneys close to each other and one is breathing out smoke while the other is breathing in outside air to equalize air pressure in the house. Here is a link to an article and a picture diagram of the issue.

The Chimney Balloon is used regularly buy chimney sweeps and homeowners to correct smoke crossover issues. If you use a Chimney Balloon to seal the basement fireplace chimney it will force the house to find another path to draw air in from other than the basement chimney flue. This, therefore, eliminates the smoke being drawn back into the house.

You can use the Chimney Balloon as a temporary or permanent solution to this chimney smoke crossover issue. The Chimney Balloon will function as your damper once it is installed so there will be no need to do anything with the old metal damper. So you can save the rest of the chimney funds to hit the other projects on the old honey-do list. – Jason

How good does the Chimney Balloon really work? What testing has been done?

How good does the Chimney Balloon really work? What testing has been done?

Q: Jason, How good does the Chimney Balloon work? How much air can I really expect to stop from coming in through my fireplace?- SH

A: SH, The amount of money you save with a Chimney Balloon is directly proportionate to how bad your damper leaks. If you have no damper, or you keep your damper open, the Department of Energy says you will consume 30% more fuel to heat your home (conservative estimate). If you do have a damper (and it is in good shape) you are better off, but a metal damper is still not a good way to hold back the cold and keep in the heat.

Imagine you install a metal flap damper on your front door as a mail slot. Aesthetically that wouldn’t be pretty, but it is certain you would feel the cold convecting through the metal, and if you have the slightest warpage to the metal you are going to feel a full on draft. The reason we don’t think about our dampers (and the cold air it lets in) is that it is out of sight up our chimney not on the front door.

One good way to tell if you need a Chimney Balloon is if you stick your hand in the hearth of your fireplace and you notice a temperature change. If it is colder in there, a Chimney Balloon will without a doubt save you money. If you notice no change a Chimney Balloon will help, but it won’t help as drastically because your damper is in better shape than most.

If you want more definitive numbers data. Here is a link to a third party Chimney Balloon field test review that was done with a blower door on a ranch home comparing the Chimney Balloon to a damper, glass doors, and open damper condition. – Jason

Should I buy a standard size Chimney Balloon or a custom size Chimney Balloon?

Should I buy a standard size Chimney Balloon or a custom size Chimney Balloon?

Q: Jason, My chimney opening measures 33″ x 6″ just above the damper. In one place on your website, it says to go with a Chimney Balloon that measures within 6″ in either direction. Therefore, I was going to choose the 30″ x 9″ Chimney Balloon. However, when I selected that Chimney Balloon, it said that it would only work on chimneys that were up to 6″ smaller (not larger). Please let me know whether this Chimney Balloon would work and, if not, what I need to order.- UT

A: Dear UT, For a 33X6 opening I would recommend a 33X12 stock Chimney Balloon. The 30×9 would be too small in length for your application. You could also call our customer service line (608-467-0229) a 33X9 Custom Chimney Balloon for the same price. The only difference is a custom Chimney Balloon requires a 14-day turnaround before it ships. Either option will work well.- Jason

How can I stop the cold draft and odor from a Pot Belly Stove with a bad damper?

How can I stop the cold draft and odor from a Pot Belly Stove with a bad damper?

Q: Jason, I have a pot belly stove with a bad damper on it. Can I use this Chimney Balloon to stop up the chimney?I believe the stove pipe is 8.25″ ID – PS

A: Dear PS, If you can reach into your stove and touch the location where the chimney meets the stove you can use a  9×9 Chimney Balloon.

You will put the Chimney Balloon into the pipe right where it attaches to the firebox. The handle of the Chimney Balloon will be sticking into the firebox and the Chimney Balloon will plug the pipe. Most of the time on a pot belly stove the butterfly damper is ways up the flue pipe so that will not be a factor at all. I would recommend you put the Chimney Balloon reminder card on the pot belly stove handle if you use that stove at all.- Jason

Can a Chimney Balloon help me keep in my cool A/C air in the summer?

Can a Chimney Balloon help me keep in my cool A/C air in the summer?

Q: I live in an area that is very hot (115F) in the summer, even though it goes below freezing in winters. Should I remove my Chimney Balloon in the Spring of each year due to the heat that is coming? Thank you, – PU

A: Dear PU, There is no real need to remove the Chimney Balloon in the summer even though the temperature gets that hot. As a matter of fact, I would encourage you to leave it in to help keep out the infiltrating heat. Air sealing helps you in the summer months as well as the winter. No doubt about it that kind of outside temperature is crazy hot! But your Chimney Balloon can handle it.- Jason