Sometimes there is a draft that blows out the pilot. The regulator (the little box that the thermocouple connects to) may also be defective. You could start by replacing the regulator and checking the installation for bad drafts, but that is about as far as I’d recommend going as a DIYer. While you’re at it, make sure that the gas supply has a drip stub to catch moisture and particulate matter, a frequent cause of problems. If you can’t correct the problem with this advice, do yourself and your family a favor by calling in a licensed gasfitter/plumber.
Here is a simple solution to your problem – get your head down and look at the pilot burner when it going – is it burning a clean blue in colour or does it have some slight yellow tipping – I suspect it will be the latter which requires a gas serviceperson to resolve for you. Either way the problem is only minor and you should not be up for big bucks for the repair job.
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