This stuff does the trick for an outside or exposed oil tank. We have a 275 gallon vertical with a short feed line into the house and haven't had any issues since with gelling. If anything it's piece of mind when your oil sits in the tank all summer or you moved into a house not knowing how long its been there, as we did. Well worth the purchase and will buy again.

I have an outdoor oil tank at my home in Pennsylvania and have had problems with condensation affecting the oil fuel- but not any time since after I began using this product.

This stuff works great! In winter months, my oil company will fill my indoor tank and shortly after, my furnace won't fire. No so good when you have to go to the basement at 430 am and retire it cause there's no hot water and the house is cold. I think there was water in the oil. This treatment has completely stopped unwanted basement trips. I add it to every new delivery and my furnace fired all winter long. Great product. Thanks

Simple prevention. I use oil heat, and the location where the tank is can get cold. Oil company offered to sell me an additive for $30. I asked them what they would put in. "Hot 4 in 1". While I was on the phone with them, I googled it and ordered two on Amazon. Saved 50% off what I would have paid. Also, gives a bit more peace of mind for less oil heat troubles.

We ordered this product on the recommendation of our plumber after having issues with 'sludge' clogging our lines to our furnace. I received the usual notifications from the seller when the product was shipped but after a week I was still waiting for it to arrive. I sent an email to the seller and they assured me it was shipped and delivered to our address. UPS confirmed this...however I didn't receive the item. The seller assured me that if the UPS tracking procedure didn't solve my problem, they would happily ship another bottle out to me asap! Turns out the box WAS delivered to my house and accidentally swept into our entryway closet. My bad!! The sellers had a great sense of humor about my blunder! I have since added the Hot 4-in-1 treatment to our oil tank and so far, we have not experienced any more issues with the furnace not firing on when we turn the thermostats up to 69 degrees!