Kitchen Gas Appliances - Range Hood Vent System
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02-25-01, 09:39 AM
We are in the midst of renovating a home and we are installing a kitchen. There is a chimney running along a wall in the kitchen against which we are placing our high-end professional range. We want to install a high capacity hood vent for the range and tap it into the existing chimney flue. Is there any reason why we could not tap into a flue that is also being used by a hot water heater in the basement? The flue would serve to vent gases from the hot water heater and food odors from the kitchen. Is there any fear that gases might come into the kitchen from the hot water heater through the hood vent?
HELP!?!?!?!?
HELP!?!?!?!?
dkerr
02-25-01, 10:07 AM
I am not specificly familier with any code covering this, but my gut instinct says NO. You don't want exhaust flumes from the furance and water heater coming into the kitchen, a dangerous and very unhealthy situation. I assume that your water heater burns gas and the chimmey is being used to exhaust the flumes to the outside.
Sharp Advice
02-25-01, 10:15 AM
Hi: Lisa C.
Based on the information you posted, the answer is definitely not. Do not interconnect the two exhaust vents!
The reason is the range hood has a fan which will cause a positive air pressure force in the flue of the water heater. This air pressure will force some of the air down the water heaters flue.
Should the water heater be operational, at the same time the hoods exhaust fan is on, the fumes from the water heater will be negetively effected. This negetive air flow can cause servere burner flame distortion in the firebox of the water heater.
The range hoods forced air exhaust fan will cause what is known in the industry as "spillage at the downdraft diverter."
The spillage is a reversed air flow which means some of the water heaters fumes will come out the diverter <spill> and into the room where the water heater is.
These fumes, contain a slight amount of carbon monoixides when the water heater is operating normally. However, should the water heaters flames, in the firebox, become distorted by reverse air flow caused by the range hood, the fumes will contain an extremely high level of CO.
Enough to kill anyone and everyone in the area/house depending on the tanks location. This could happen within minutes if CO fumes levels are high enough or over hours. Lower levels, over longer time frames will cause flu like symtoms, etc.
I highly recommend you check with the building and safety department in you area for codes pertaining to this topic prior to any installations. Your safety and health could be at risk if not.
Based on the information you posted, the answer is definitely not. Do not interconnect the two exhaust vents!
The reason is the range hood has a fan which will cause a positive air pressure force in the flue of the water heater. This air pressure will force some of the air down the water heaters flue.
Should the water heater be operational, at the same time the hoods exhaust fan is on, the fumes from the water heater will be negetively effected. This negetive air flow can cause servere burner flame distortion in the firebox of the water heater.
The range hoods forced air exhaust fan will cause what is known in the industry as "spillage at the downdraft diverter."
The spillage is a reversed air flow which means some of the water heaters fumes will come out the diverter <spill> and into the room where the water heater is.
These fumes, contain a slight amount of carbon monoixides when the water heater is operating normally. However, should the water heaters flames, in the firebox, become distorted by reverse air flow caused by the range hood, the fumes will contain an extremely high level of CO.
Enough to kill anyone and everyone in the area/house depending on the tanks location. This could happen within minutes if CO fumes levels are high enough or over hours. Lower levels, over longer time frames will cause flu like symtoms, etc.
I highly recommend you check with the building and safety department in you area for codes pertaining to this topic prior to any installations. Your safety and health could be at risk if not.
02-26-01, 12:04 PM
Tom,
Thanks for the quick reply. We obviously nixed the vent thru flue idea. Can you vent a range hood down? We could go down the floor to the basement and then out of the house on the side of the house. Does that make sense? We would like to have a solution so we can finish our drywalling in the kitchen. If you don't know...what kind of professional would do range hood installation?
Thanks,
Lisa
Thanks for the quick reply. We obviously nixed the vent thru flue idea. Can you vent a range hood down? We could go down the floor to the basement and then out of the house on the side of the house. Does that make sense? We would like to have a solution so we can finish our drywalling in the kitchen. If you don't know...what kind of professional would do range hood installation?
Thanks,
Lisa
Sharp Advice
02-26-01, 07:23 PM
Hi:Lisa
You asked if all this makes sense. The answer is yes. Primarily because you write well and clearly discribed the situation. Needless to say, on my end that helps out tremendously. Thanks.
In regards to the downward vent from the range hood, I can't say for sure. Never seen one installed that way. May be because the fan won't be able to force the fumes from over the stove out fully.
Upwards, the fan blower in the hood gets some help do to the fact that the warmer air aids the lifting process. <Warmer air rises.>
Several suggestions to offer.
Try contacting the range hoods manufacturer and ask them the same question. Be prepared to offer some facts. Like the distance of the vent tube downwards, sideways, straight, etc. total feet to the exterior, etc. I am sure they will have a definite answer to the question.
Have you considered having the vent tube going horizontal behind and thru or above the cabinets to the exterior? Possibly some other non typical installation simalar to this maybe.
You could get some alternate suggestions by asking installation contractors. The can be located in the phone book, ask at the building supply yard. Ask the hood manufacturer or inquire at the city building department. Contractors license board or post that exact question regarding installation contractors, on this web site, in the appropriate forum.
Since I am not an installation contractor etc. I hope something I have to offer here helps you.
Good Luck,
Tom
You asked if all this makes sense. The answer is yes. Primarily because you write well and clearly discribed the situation. Needless to say, on my end that helps out tremendously. Thanks.
In regards to the downward vent from the range hood, I can't say for sure. Never seen one installed that way. May be because the fan won't be able to force the fumes from over the stove out fully.
Upwards, the fan blower in the hood gets some help do to the fact that the warmer air aids the lifting process. <Warmer air rises.>
Several suggestions to offer.
Try contacting the range hoods manufacturer and ask them the same question. Be prepared to offer some facts. Like the distance of the vent tube downwards, sideways, straight, etc. total feet to the exterior, etc. I am sure they will have a definite answer to the question.
Have you considered having the vent tube going horizontal behind and thru or above the cabinets to the exterior? Possibly some other non typical installation simalar to this maybe.
You could get some alternate suggestions by asking installation contractors. The can be located in the phone book, ask at the building supply yard. Ask the hood manufacturer or inquire at the city building department. Contractors license board or post that exact question regarding installation contractors, on this web site, in the appropriate forum.
Since I am not an installation contractor etc. I hope something I have to offer here helps you.
Good Luck,
Tom