Please help me. I don't know what to do. After a short vacation, my oil
furnace won't turn on automatically for hot water. Nothing else changed.

My home has a 19 year old oil furnace which says Burnham RSM-126 on a
plate. It will not turn on automatically for hot water.

I have to keep hitting the start button to make it turn on to heat the hot
water.

This problem started after I had the water and furnace turned off for 2
weeks while I headed off on vacation.

Any suggestions on how I can troubleshoot this on my own? Or is this one
item which isn't home testable since it involves oil?

Donna