Oil burner reset button problems - after rainy days?

I have a reset-button problem that I think might be related to condensate in the fuel. I'll provide as much detail as possible in hopes that someone can enlighten me on what to do about this problem. (It's a long post - I appreciate your patience...)
I have a 10-year old boiler that is used for steam heat and for hot water. I've lived in the house for two years. The house is in Massachusetts. The oil tank is in an unheated garage and the boiler is in the basement which stays warm in the winter because of all the steam pipes. We had no problems the first summer but in the fall, shortly after our first oil burner service call, we had to start hitting the reset button about once or twice a week. The pump would pump the oil but the flame was not catching in the allotted time period (around 10 seconds or so). When this happens, one or two hits of the reset but will restart the boiler. At first I thought the service guy screwed something up but the same thing happed this fall as the same time of the year so I think it's more related to temperature then something the service guy did.
I have a two-year free service plan and they have been out about 10 times trying one thing or another to fix it. (This company has a reputation for being very good and but expensive.) The things they do seem to help a little so that sometimes I only have to hit it once a month. They have concluded that it is a flow problem because the tank is in unheated space and have been adding something like dry gas with every fill. I think they call it Actane. (As a side issue, I watched the guy fill the tank last time and he didn't add anything so I don't really know if it is being added or not. Is this something I can buy and add myself?)
I don't think it is cold flow problem because it once happened on a day last spring that was 70 degrees and it has happened about 10 times this fall when the temperature was around 40 degrees. Also, I can see a mist of something and can usually smell fuel when the thing is trying to start so I know that something is flowing in there. (Once it sort of backfired and blew smoke out of the chimney vent)
This year, I starting writing down all the conditions of when the thing failed to start and I noted a curious thing - about 70% of the times if failed, it had rained the day before. One day where it rained heavily the day before, It failed to start three times over the course of the day. And on one of those times, I had to press the reset button four times before it finally started.
I'm going to take a guess here and assume that this is related to condensate in the fuel. Moist air on the rainy day is getting into the oil tank and when things cool down at night, the water vapor condenses and I end up with water in the fuel.
Does this sound like the cause of my symptoms? If so, what can I do about it short of bringing the oil tank into the warm basement? One thought is tipping the oil tank away from the feed so that the water settles at the other end of the tank and adding the dry gas stuff and any anti-corrosive treatments so the tank won't rust from the inside out. Is there any kind of water separating filter I can install? I know that boaters with diesel engines have Racor brand fuel filters with glass bowls and a drain valve at the bottom for releasing water.
Is that anything else that can be causing this? I once had a car with a cracked distributor cap and only acted up on rainy days. Could the sparking system be affected by moisture? (I currently don't have a rain cap at the top of my chimney.)
Thanks, Scott
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wrote:

Your post is amusing at best. Here is what you need to do: 1) Leave your oil boiler alone and STOP pushing the reset button (especially more than once. Keep it up and you will be learning a lesson the hard expensive way). 2) Ditch your present oil service company IMMEDIATELY. They dont have a freaking clue what they are doing. 3) Now comes the hard part. Find a good reputable oil hvac contractor. Here is a clue. If they dont come out with a digital combustion efficiency analyzer, smoke pump, draft gauge (and the knowledge how to use them) immediately show them the door too. 4) They should analyze everything. Boiler, proper nozzle and settings, flue length/size, etc. Look at the whole picture. Its not rocket science but it is a science. Bubba
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