Heating a kitchen with a gas oven

[HayZee518]

There was an article in a Buffalo NY newspaper that cautions about using a gas stove to heat a house after the power went out. They say a gas stove produces carbon monoxide which is a poisonous gas. OK, what happens when you are cooking a turkey for more than 6 hours? No carbon monoxide?? Explain this one..

[LazyPup]

The answer to your question is really a two part answer.

1. When cooking their is generally someone in attendance in the kitchen and periodic opening or closing of doors, whereas if you were to use the oven for heating the risk is everyone could be asleep and no one notice the buildup.

2. The real risk is not carbon monoxide but rather it is overheating the oven. When being used in the prescribed manor the oven door is normally kept closed so as the air in the oven is heated it is constantly beings sensed by the thermostat and the burner flame regulated accordingly. When the oven door is left open for heating purposes the majority of the heat then channels out the oven door and the thermostat sensor, which is typically in the rear upper part of the oven is outside the main airflow pattern. This results in the thermostat sensing a false reading and keeping the burner on full fire for the duration of the operating time and the bottom of the oven and lower portion of the oven walls are then heated well above the normal safe operating temperatures.

[HayZee518]

But carbon monoxide is still produced either from the burners OR the oven. I know about the stat cycling the burner on and off. OK here's another one. My outside grill is propane. My stove inside is propane. They say NOT to burn a grill inside because of the CO produced. My propane range produces CO off the burners just like the burners off the grill. The grill is tended to by a body just like the propane stove inside.

[LazyPup]

In fact, you are correct, code does require additional venting whenever a gas appliance is installed in a "Confined Space"

A confined space is considered any space less than 50cu.ft for each 1Kbtu/hr.

A freestanding kitchen range is rated at an average of 65KBtu/hr

Thus in this example a confined space would be a kitchen that is less than 65x50 = 3250cu.ft.

Allowing an 8' ceiling we could then compute 3250/8= 406.25sq.ft

Unsing the square root of 406.25 we get a 20'x20'x8' room or equivalent.

When a gas appliance is installed in a confined space we must then provide two vents from the confined space to an adjacent unconfined space and each opening must be a minimum of 100sq.in. One opening must be installed with the top not more than 12" below the ceiling and the second one must be installed with the bottom of the opening within 12" of the floor.

Most codes allow a variance for a kitchen range providing the there is no door on the doorway from the kitchen to an adjacent room or if there is open airflow between the adjacent rooms such as a serving window type pass through or open counter space between the kitchen and adjacent room.

While this is not enforced nearly as much as it should be, in many jurisdictions a sharp eyed inspector will require a gasseous fired kitchen range to have a vent hood that is vented directly outside when the room dimension is less than the prescribed minimum for an unconfined space.

[leodlion]

There was an article in a Buffalo NY newspaper that cautions about using a gas stove to heat a house after the power went out. They say a gas stove produces carbon monoxide which is a poisonous gas. OK, what happens when you are cooking a turkey for more than 6 hours? No carbon monoxide?? Explain this one..

When you cook a turkey, you use the gas oven. The CO produce goes not go into the kitchen, its vented out of the house. So, no harm done. When you use the gas stove to product heat, the CO is inside the kitchen. The buildup of CO plus the depletion of O2 becomes a deadly combination.

What if you cook the turkey in the gas stove? Nobody cooks turkey in the gas stove.

... My outside grill is propane. My stove inside is propane. They say NOT to burn a grill inside because of the CO produced. My propane range produces CO off the burners just like the burners off the grill. The grill is tended to by a body just like the propane stove inside.

In this example, the danger from the grill and from the gas range is the same. The only difference I can see is that the grille may topple and cause a fire.

[LazyPup]

"When you cook a turkey, you use the gas oven. The CO produce goes not go into the kitchen, its vented out of the house."

WRONG__ Sometimes built in ovens are vented to the outside but not in all cases, and in the case of a free standing range the over vents directly up through the underside of one of the surface burners as a heat recovery technique.

The freestanding range oven is only vented to the outside if there is a vented range hood and if that said rangehood is running while the oven is firing.

[leodlion]

"When you cook a turkey, you use the gas oven. The CO produce goes not go into the kitchen, its vented out of the house."

WRONG__ Sometimes built in ovens are vented to the outside but not in all cases, and in the case of a free standing range the over vents directly up through the underside of one of the surface burners as a heat recovery technique.

The freestanding range oven is only vented to the outside if there is a vented range hood and if that said rangehood is running while the oven is firing.

The exhaust gas from ANY gas oven is eventually vented out of the house - for all cases no exception. Otherwise, you will have a lot of dead people around.