A bad gas valve will not allow any gas to go to the burner or pilot light. See the article on 'Hot Water Heater Gas Valves' for the issues surrounding this device. A clogged or partially clogged vent can cause this problem. See Venting a Gas Water Heater for information on keeping your vent clear.
Definition. A hemoglobin test measures the amount of hemoglobin in your blood. Hemoglobin is a protein in your red blood cells that carries oxygen to your body's organs and tissues and transports carbon dioxide from your organs and tissues back to your lungs. If a hemoglobin test reveals that your hemoglobin level is lower than normal, it means you have a low red blood cell count (anemia). Anemia can have many different causes, including vitamin deficiencies, bleeding and chronic diseases.
HbA1c facts. 1  Hemoglobin A1c, often abbreviated HbA1c, is a form of hemoglobin (a blood pigment that carries oxygen) that is bound to glucose. 2  The blood test for HbA1c is routinely performed in people with type 1 and type 2 diabetes mellitus. 3  HbA1c levels are reflective of how well diabetes is controlled.