UPPER MERION TOWNSHIP, Pa. (CBS) – A defective heater sent an odor of natural gas through a home in Montgomery County Sunday morning.

Firefighters and workers from PECO Energy’s gas division were called out to the 100 block of Holstein Road in Upper Merion Township at about 8 a.m. Three residents who fell ill due to the fumes were removed from the home and taken to Montgomery Hospital in Norristown for evaluation.

Workers were able to secure the heater, but PECO is trying to determine why the heater defect occurred.

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