Hot Pot: A Tool for the Standardized Testing of Carbon Monoxide and other
Emissions from Gas Range Burners
The CO Hot Pot is a device which allows measurement of carbon monoxide
and other emissions from gas range-top burners. Carbon monoxide emissions
may be measured in a repeatable and standardized manner with this device.
Those needing to measure carbon monoxide and other emissions from gas
range-top burners include natural gas utility service personnel, LPG service
personnel, low-income weatherization energy auditors, and house inspectors.
The CO Hot Pot is not for sale. We attempted to patent it, but found
that the the Gas Research Institute (GRI) published a paper--Interlaboratory
Program to Validate a Protocol for the Measurement of NO2 Emissions
from Rangetop Burners--in December of 1994. This paper included a
description and photographs of a similar, but very expensive emissions-capturing
device. Because this paper was published before we applied for the patent,
the GRI device is considered to be "prior art," thus disallowing
our patent for the CO Hot Pot. As a result, we are not manufacturing or
selling the CO Hot Pot. If you wish, you may make your own CO Hot Pot.
The directions for
Making a CO Hot Pot
and Using a CO Hot Pot
are part of
this Web Site]
The device is used in conjunction with a carbon monoxide measuring meter,
such as the Monoxor II, manufactured by Bacharach. Meters such as the
Monoxor II measure carbon monoxide in units of parts per million (ppm).
There are at least four other manufacturers of carbon monoxide measuring
Carbon monoxide emissions are easy to measure for all combustion appliances
except gas range-top burners. This is because all combustion appliances
(except gas range-top burners) have an emissions-containing device, e.g.,
the vent pipe of a gas or oil furnace, the vent pipe of a gas dryer, and
the vent port of a gas oven. A gas range-top burner is an open flame without
a vent pipe or port to contain the combustion emissions, thus making it
impossible to sample and measure various combustion bi-products with any
degree of accuracy. The CO Hot Pot is an emissions-containing device that
makes standardized and repeatable testing of carbon monoxide or other
emissions from a gas range-top burner possible.
The CO Hot Pot is set on the burner grate of the gas range-top burner.
The steel probe of the carbon monoxide measuring meter is inserted into
the hole on the side of the CO Hot Pot (A grooved hex head bolt protruding
into the center of the device supports the steel probe). The carbon monoxide
measuring meter is turned on and then the gas burner is ignited. The CO
Hot Pot directs the combustion emissions upward past the gas-intake end
of the steel probe of the carbon monoxide measuring meter. The CO Hot
Pot contains the emissions in the same manner as the vent pipe on a gas
furnace. The stainless steel pot at the bottom of the CO Hot Pot (sitting
on the burner grate) allows the gas flame to impinge upon it, thus simulating
a cooking pot. The stainless steel pot at the bottom of the CO Hot Pot
may be filled with water for the test (wet test) or my be left empty (dry
A variation of this prototype will have a teapot-type device at the bottom
instead of a stainless steel pot. This variation is intended for wet tests
only (a wet test more closely simulates the every-day use of a gas range-top
burner, i.e., people seldom heat empty pots or pans on a range-top burner).
The spout of the teapot-type device protrudes through the wall of the
metal pipe. For an emissions test, the teapot-type device is filled with
water and placed on an ignited gas range-top burner. The burner combustion
by-products (emissions) rise inside the metal pipe, but the water vapor
from the hot and boiling water in the teapot-type device exits through
the spout to the outside of the metal pipe, preventing water vapor damage
to the carbon monoxide measuring meter.
The CO Hot Pot can also be used to measure the "air free" carbon
monoxide emissions from a gas range-top burner (wet test or dry test).
To do this, a carbon monoxide sample of the emissions is taken with the
CO Hot Pot and an oxygen sample is taken from the same emissions with
the CO Hot Pot. The carbon monoxide sample is then adjusted to simulate
oxygen-free conditions. The equation used for this adjustment is:
COaf = COppm
[1 - 4.78(O2)]
Where: COaf = Carbon monoxide, air free ppm.
COppm = Measured combustion gas carbon monoxide ppm.
O2 = Percentage of oxygen in combustion gas, as a decimal.
A variation of this bowl unit has a stainless steel teapot-type device
at the bottom instead of a stainless steel pot. The spout of the teapot-type
device will protrude through the wall of the metal pipe. For an emissions
test, the teapot-type device will be filled with water and placed on an
ignited gas range-top burner. The burner combustion by-products (emissions)
rise inside the metal pipe, but the water vapor from the hot and boiling
water in the teapot-type device will exit through the spout to the outside
of the metal pipe, preventing water vapor damage to the carbon monoxide
For more information, please see:
Making a CO Hot Pot, instructions for making a device for measuring carbon
monoxide from gas range-top burners, and
a CO Hot Pot, instructions for standardized use for measuring carbon monoxide
from gas range-top burners.