"Heating the Water The thermostat controls the temperature of the
water inside the tank. Normally you can set the temperature between 120
and 180 degrees Fahrenheit (49 to 82 degrees Celsius). It is generally
recommended that you keep the temperature between 120 to 140 degrees F
(49 to 60 C) -- especially if there are children living in the house --
to prevent scalding. It also saves energy." and more at:
http://home.howstuffworks.com/water-....htm/printable
how your boiler works:
http://home.howstuffworks.com/how-to....htm/printable

usual definition clarification:
furnace=heating of air
boiler or hydronic =heating of water

lookup boiler manual online. look up any manuals online for any
connected parts that control your devices. like honeywell. depending on
what type of heating this is there will be everything with operating
manuals or instructions and they will all need to work together. if the
third zone is a forced air furnace, i don't know. if it is a boiler, it
may be along for the ride as a passive loop with the system operating
year round. if it has an active burner or heating element find its
temperature control or zone control valve.


El Penguini wrote:
I have a potable hot water system that uses the third zone off of my furnace
to heat a coil in a storage tank.

While the water is hot, it isn't hot enough for my liking.

Can someone give me a clue on how this system works, and what settings I
should be looking for?

Thanks
Peter