On Sun, 10 Aug 2008 11:48:55 -0700, Donita Luddington wrote:

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

Sounds like you have some sort of circulating Hot Water home heating
system that also supplies heated water from a oil fired boiler to a large
potable hot water tank by way of separate piping and a circulating pump.
This is now a rare home heating system for most of the USA and Canada.

However, and whatever, device that controls the temperature inside the
H.W. tank and acts as the temperature set thermostat isn't getting it's
signal sent to your oil fired boiler and pump. It could be anything from
a simple switch you forgot to reset, to some limit switch that needs to
be manually bypassed until boiler gets up to some temp range, to....

It may not be your furnace (boiler) but some control electronics for the
boiler and H.W. Tank.

Sorry to say, but due to the your description, you may need a
professional to make a house call.

Best of luck.