Gas and Oil Home Heating Furnaces - Pilot lite on furnace blowing out

I have a forced air gas furnace (Ruud) that has a pilot light. During the winter, the pilot light blows out mysteriously -- It doesn't blow out in the summer so I don't think it's due to a draft of some kind. I think it may be a thermocoupler but I'm not sure.

I'm hoping one of the "experts" may have run across this in the past and can help me with the diagnosis.

Thanks !!

What sort of flame do you have ?
How long do you have to hold the button down when you relight it?
If you are having to hold it down more that 20-30 sec thats a sure sign the 1) the flame is not heating the thermocouple enough or
2) The thermocouple is getting weak.

If the pilot is on all summer do you have an AC on this furnace?Could be there is a crack in the heat exchanger that opens when hot and the blower blows it out. Try the T/C and get a new one cost about $5.00. Clean out the pilot venturi also.;) ED

I do have A/C on this furnace with no blowouts over the summer months.

Turn gas off and vac all the burners and pilot light good. Then relight. For $5.00 Id get a new T/C;) ED

Thanks for everyone's suggestions.

I verified that the TC was OK (25 mV). The pilot assy was pretty clean but it does blow out fairly easily. I called in support from an expert who rigged up a re-igniter circuit that should relight the pilot light automatically next time the little bugger decides to blow out. It senses when the flame is out and sends a spark before the TC shuts off the gas -- pretty cool stuff ! Still a mystery on why it keeps blowing itself out but this should solve the problem.

The funny thing was that the HVAC guy had just come from another house with the exact same Ruud furnace that was having the same problem -- he rigged up the re-igniter for them also.

Thanks again !!