Plumbing in the Home/water heater
I have a water heater that is two years old. It is propane fueled and is located in a water heater closet accessible from the exterior of the house. The door to this closet has two screened vents (high and low) and the water heater is vented through the roof. The house is in a coastal area with LOTS of wind. About four weeks ago, my wife couldn't get hot water to the shower so she checked to see why and discovered the water heater pilot was out. She re-lit the pilot and a week later our son visited the house (it is a vacation/second home) and had hot water the first two nights here, but cold water the morning last morning. So he re-lit the pilot. My wife and I returned a week later and have had a week of hot water. This afternoon, we discovered the pilot was out again. I just kinda dismissed it to the wind- cause it's been very windy the last few weeks, but i guess I can't say it's been windier than the last two years. After almost two years of no problems, why would we be experiencing this now? I don't suspect it is a good idea to try to restrict the ventilation a little bit to so if it is wind related?
Combustion air requirements are typically 100 in.² if the area/enclosure that contains the water heater is less than 50 ft.². This is required to be divided into two equal portions with 50% within 12 inches of the top of the enclosure and 50% within 12 inches of the bottom of the enclosure.
That being said, this can be accomplished in a number of ways and NO
it is not a good idea to restrict this combustion air intake area.
If the current openings are just "screened" you could change them to a louvered style vent panel. Note though that a louvered vent is de-rated by 50%. That means you would need a vent twice as big to get the same effective venting area. You may be able to accomplish the task by having a sheet metal "wind" baffle made to fit over the existing vent openings.
Another possibility is that the the flu vent is back drafting and blowing out the pilot. Possibly changing the vent Terminator To a different style might help.
Lastly, it might be a good idea to have your local gas provider check the system out to make sure that the inner draft panel (there are two panels at the bottom of the heater, an outer one and an inner one over the combustion chamber) is properly in place and that the thermocouple and gas valve are operating correctly.