I had my house built 10 years ago and purchased a stove from Sears which was originally natural gas but set up as propane from the kit it was shipped with. The stove works but I noticed it took a long time for my cook. Sometimes I cook at my dad house and noticed a couple cups of water took 2x as long on my stove versus his. I can never stir fry because my pan takes a long time to get hot and when I put food in then it cools off and will take a long to time to get hot. I thought I just had a poor quality stove but a couple of years ago we remodeled the kitchen and bought a "high end" dual fuel stove. This stove also takes a long time to cook and I still can't do stir fry. I then thought it was the propane but my sister bought a house with a stove converted to propane and it works fine over there. She can boil water in a minute where I have to wait 5. Does anyone have any ideas?