Draft Issue

[scott123]

Here is my configuration:

I had my chimney inspected two days ago. At the base, I found about 5 pieces of terra cotta liner all about this size:

When the tech lit a piece rolled up newspaper at the base of the chimney, the newspaper went out. Twice. The chimney was relatively cool at the time.

There are no visible obstructions inside the chimney and there aren't objects near the chimney opening to affect air flow.

I'm in the process of purchasing a flexible liner kit, but my concern is that I'll put the liner in and it won't solve my draft issue. Am I missing something in this equation?

Also, is this newspaper technique reliable? Was my technician trying to pull a fast one over on me in an effort to get me to quickly purchase a liner (at 3 times the price) from him?

Lastly, there is a bedroom on the basement floor and I'm a little freaked out by carbon monoxide poisoning. I'll be putting a liner in within the week, but in the meantime, do the cheap ($20) home depot carbon monoxide detectors work?

 

[colebrookman]

https://www.hearth.com/econtent/index.php/forums/viewreply/185172/

Lastly, there is a bedroom on the basement floor and I'm a little freaked out by carbon monoxide poisoning. I'll be putting a liner in within the week, but in the meantime, do the cheap ($20) home depot carbon monoxide detectors work?

YES they work. Buy two it's cheap insurance!!
Do not go to sleep without that CO detector unless you like to gamble with your life and all others sleeping in your house. Its been said many times before, Co is odourless, colorless and tasteless, it kills even at low levels and death is permanent. Please do it now.

 

[scott123]

not supposed to have 2 appliances in 1 chimney per code.

Are you sure about that? Could you be thinking about wood appliances?

I just put in a new furnace last year and the local inspector went over the entire setup with a fine toothed comb.

 

[colebrookman]

Pook is absolutely correct. Someone messed up and it could cost your life.

 

[stanleyjohn]

Here in Ct you cant have two heat devices in one chimney flume!its against building code..

 

[scott123]

This is the code for NJ (and many other states):

M1801.11 Multiple-appliance venting systems.
Two or more listed and labeled appliances connected to a common natural draft venting system shall comply with the following requirements:
1. Appliances that are connected to common venting systems shall be located on the same floor of the dwelling.
Exception: Engineered systems as provided for in Section G2427.
2. Inlets to common venting systems shall be offset such that no portion of an inlet is opposite another inlet.
3. Connectors serving appliances operating under a natural draft shall not be connected to any portion of a mechanical draft system operating under positive pressure.
M1801.12 Multiple solid fuel prohibited.
A solid fuel-burning appliance or fireplace shall not connect to a chimney passageway venting another appliance.

I'll be picking up a CO detector tonight (thanks).

Now, the draft issue. Is there any reason why a S/S liner won't give me a good draft?

Also, does liner insulation help for draft issues?

 

[jtp10181]

You COULD have two GAS B-Vent appliances into the same flue in some areas, but you should never have an oil and gas dumping into the same flue. The inspector must have assumed the furnace was gas.

You might have to get a power vent kit for the oil furnace and then reline the chimney for the water heater. Not sure if you could get two liners down there and have them installed legit. Not sure on specifics for oil and gas liners.

 

[billb3]

I've always understood the rules as "fuel types" not being mixed.
Rules change. There may even be some grandfathering involved.

My dad had a wood stove and oil burner in the same chimney. A no-no, but the wood stove was just set up for emergency use. It used to get used but mom's allergies got worse.
He probably disconnected it if anyone besides the oil burner guy was t check it out.
There was an incinerator there at one time, too.

(was supposed to be better than a 55 gallon drum in the back yard. I kinda doubt it)

 

[scott123]

Okay, here's more code (Bold Mine):


2006 International Residential Code® New Jersey Edition

G2427.5.6 (503.5.7) Chimneys serving equipment burning other fuels. Chimneys serving equipment burning other fuels shall comply with Sections G2427.5.6.I through G2427.5.6.4.

_____G2427.5.6.1 (503.5.7.1) Solid fuel-burning appliances.
An appliance shall not be connected to a chimney flue serving a separate appliance designed to burn solid fuel.

_____G2427.5.6.2 (503.5.7.2) Liquid fuel-burning appliances. Where one chimney flue serves gas appliances and liquid fuel-burning appliances, the appliances shall be connected through separate openings or shall be connected through a single opening where joined by a suitable fitting located as close as practical to the chimney.

 

[jtp10181]

You COULD have two GAS B-Vent appliances into the same flue in some areas, but you should never have an oil and gas dumping into the same flue. The inspector must have assumed the furnace was gas.

You might have to get a power vent kit for the oil furnace and then reline the chimney for the water heater. Not sure if you could get two liners down there and have them installed legit. Not sure on specifics for oil and gas liners.

OOPS i dont htink u can vent a forced draft gas appliance with a natural drafter into same vent. they both use b-vent.
waterheater has draft hood & furnace has barometric damper which is probly like natural draft, after proper adjustment.

That's why I said B-Vent, that implies natural draft. When speaking of the power vent kit for the oil unit, this would punch out the side of the house and free the entire flue up for use with the water heater.

 

[Redox]

Since I am not an authority on code, don't take this as anything but an observation. I have seen literally hudreds of oil furnaces and boilers installed with a gas water heater in the same flue. Both of them operate under a negative pressure and aren't likely to condense. The rule I always heard was solid fuel must be on its own flue. Local codes take precedence, obviously.

I am wondering if the draft problem might be caused by the chimney being on the outside of the house? These are notorious for poor draft when they are cold. I have a water heater in our house that is vented into an oversized flue on the outside of the house. The oversizing happened when we replaced the furnace with a condensing model that vents out through the sidewall. The water heater "spills" flue gases for a couple minutes when it fires up, but has never registered a blip on any of the 3 CO detectors in the house. I know I need to run an insulated liner down the existing chimney to correct this, but I may replace the water heater with a high efficiency direct vent unit that wouldn't use the chimney at all. I should be able to get a 4" insulated liner down the old terra cotta flue with no problem, if I don't replace the water heater. BTW, I am using the Nighthawk CO detectors that have a digital display showing PPM, and I have never seen it read anything but "0".

Chris

 

[scott123]

I am wondering if the draft problem might be caused by the chimney being on the outside of the house?

It's kind of hard to tell in the pictures, but the chimney runs up the center of the house. Thanks for addressing my question, though.

I took the pieces of liner out right before the technician did the draft test and they were definitely cool to the touch. I'm 99% certain that it's a temperature issue. The oil furnace pumps out a lot of heat- the b vent gets hot, so I'm certain that the terra cotta liner gets heated as well, which, in turn gives me good draft (from the oil furnace). The gas water heater on the other hand, I'm not so sure about.

 

[Dave T]

I have an old Tarm ot 70 multi fuel,oil and wood that I only burn oil in right now but it ran in the basement exclusively for 22 years and a common chimney was used Is there different rules for multi fuel furnaces,maybe Craig could enlighten us on how Tarm has done this for many years and made good on it..

 

[heaterman]

It's perfectly acceptable to vent gas and oil appliances into the same flue both from a code and safety standpoint. Solid fuel along with oil and/or gas is a big no-no! The moisture from oil and especially gas combustion can do really nasty things, very rapidly, to a chimney when combined with solid fuel residue.

One can also vent for example a power vented gas water heater into the same flue serving a natural draft furnace or boiler. Venting is indeed a critical part of an installation and the manufacturer's instructions should be followed to the letter. They are based on the companies own research and the NFPA guidelines for a given circumstance.

Most problems that I have encountered with venting stem from a lack of combustion and/or makeup air available in the mechanical room or home. Common culprits are whole house exhaust fans, (should be banned IMHO) dryers, kitchen range hoods, bath fans and houses that are wrapped very tightly. Any device that removes air from the home needs to be considered in how much makeup air needs to be provided to the mechanical room. External factors would include chimneys that are located on the exterior of the house, (cold all the time negating draft) downdrafts caused by other buildings nearby, trees or other obstructions that may intermittently cause a "cap" on the chimney. The third thing is an oversized flue which is too large for the appliance vented. In this case the water heater is probably to blame for the moisture caused failure of the liner. It doesn't provide enough heat to the 8" flue to keep all the exhaust gas going up and out. This allows moisture to condense on the walls of the chimney leading to deterioration of the clay liner as shown.

A separate vent for the water heater would probably cure the problem. In this case a liner will ensure the integrity of the chimney itself but I'm not sure that it will alleviate the lack of draft issue. From the looks of the installation and the appliances vented into it, an 8" round chimney is not overly large for the application.

 

[ISeeDeadBTUs]

Have Eliot sleep in your basement. If He's ALL stiff in the morning, you have a CO problem. If only one part of him is stiff, he has the problem :lol: