Troubled Houses - A Home Owner's Resource^sm - C O Tests

We see many interesting adverse conditions during our inspections, partly because of the unlimited number of ways people can mess up a house, but also because we do a thorough inspection to reveal these adverse conditions. We hope these stories and illustrations help home owners avoid these costly conditions by learning about causes, preventions, and remedies.

Copyright HankeyandBrown.com. All rights reserved.  "Troubled Houses - A Home Owner's Resource" is a SERVICE MARK of Hankey & Brown Inspection Service Inc.  Click here for the list of topics and all articles in this resource.

THANK YOU for visiting HankeyandBrown.com.   Click here to learn more about our services, which now include IR Thermography, radon testing, and carbon monoxide tests.

Hankey & Brown Inspection Service includes carbon monoxide testing of heating systems (furnaces & boilers), gas water heaters, gas clothes dryers, and indoor ambient air.  We also test gas fired direct vent fireplaces.

Our tests are done with Bacharach single gas detectors and measure the carbon monoxide levels in the vents of the equipment and the indoor air near the equipment.  Typically, the readings indicate the equipment is operating properly (less than 100 parts per million) of carbon monoxide and no carbon monoxide is present in the indoor air.   We issue a separate memo listing the test results.

Occasionally, the tests reveal either that the equipment is making excessive levels of carbon monoxide, OR that carbon monoxide (regardless of the level) is leaking from the equipment, or spilling from the vent connector or its draft regulator. 

Recent carbon monoxide test of 53 year old boiler, leaking 44 ppm of  carbon monoxide into the indoor air.   Immediate repair or replacement recommended.

The production of elevated levels of carbon monoxide, or the spillage of any combustion fumes into the house are both very serious adverse conditions that have the potential to cause deaths to people in just a few hours.  Exposure to lesser amounts of carbon monoxide can cause chronic illness, headaches, and loss of mental & physical functions if the exposure is lengthy.   

For more information on the health effects of carbon monoxide see http://www.coheadquarters.com/CO1.htm

Testing is not required by ASHI® Standards, but our view is that in Minnesota, carbon monoxide (CO) is an essential part of a complete home inspection.

One of our CO testing experiences is told in the Sept. 2006 ASHI® Reporter artice entitled: Misunderstanding and Communication

Hot water with Carbon Monoxide

We test furnaces, water heaters, gas ovens, and indoor air for carbon monoxide (CO).  Water heaters usually make very little CO and usually all the CO goes up the vent, but not on this 16 year old water heater.

The level of CO at this water heater was over 2200 parts per million since the test instrument does not read higher than the level shown.  The heater was also SPILLING carbon monoxide at its burner door.

The CO level at the water heater burner door was over 800 parts per million.   Opening the burner door revealed that the main gas burner flame was actually touching the bottom of the tank.  This cools the flame, makes poor combustion and creates the CO. 

Our inspection was done for the buyer, but we left a warning note for the seller indicating the potential for carbon monoxide poisoning.  We learned two days later that the seller was purchasing a new water heater.

Fear of Carbon Monoxide is often used as a scare tactic by furnace service technicians to encourage the replacement of furnaces with "cracked" or damaged heat exchangers.  There can be several ways that carbon monoxide enters the home, but heat exchanger cracks rarely introduce CO into the circulating air of the house.  For more information on this topic, link to Carbon Monoxide Myths.