My furnace worked well for about 6 years. At that point I noticed an awful, propane-like smell (I'm on natural gas) from the exhaust outside my home. During my annual maintenance, the technician noted the heat exchangers were going bad.
Blood urea nitrogen (BUN) measures the amount of urea nitrogen in bloodstream. Urea is formed in liver as the end product of protein metabolism and digestion. Urea is transported to the kidneys for excretion. A normal range for blood urea nitrogen is generally 8 to 24 mg/dl for adult males and 6 to 21 mg/dl for females.Generally, a high blood urea nitrogen level means that the kidneys are not performing well, particularly if the result is above 50mg/dl.n adult men, normal range of serum creatinine is 0.9-1.3mg/dl; while in adult women, normal range of creatinine is 0.6 to 1.1mg/dl. A muscular young man will have a higher normal creatinine result than the senior people with poorer health conditions.
If kidney function begins to decline, BUN and creatinine rise. A normal creatinine depends on muscle mass and age. In general, a normal creatine is 0.5 to 1.2 milligrams per deciliter (mg/dL). A normal BUN is 7 to 20 mg/dL.Remember that different laboratories use different testing equipment, and may have slightly different ranges for normal.A small, temporary increase in either BUN or creatinine can occur during illness or dehydration; the numbers usually return to normal during recovery. normal BUN is 7 to 20 mg/dL. Remember that different laboratories use different testing equipment, and may have slightly different ranges for normal. A small, temporary increase in either BUN or creatinine can occur during illness or dehydration; the numbers usually return to normal during recovery.