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I have a fairly old (like 1950's) water boiler heating system in my house.

There is a Honeywell LA409A Aquastat high-limit thermostat attached to the system. As far as I can tell, the range of temperature controllable by the thermostat is 100°F to 200°F. If I am correct, this shuts the boiler off when the set temperature is reached.

Is there a recommended temperature for this thing? Should I set it to the high end or the low end? Would middle ground be recommended without any further knowledge of the system requirements?

For giggles, here is an original 50's Honeywell brochure on the Aquastat thermostats: http://www.heatinghelp.com/files/articles/1825/honeywell.pdf

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Anyone have any ideas about this? –  Max Vernon Jan 22 at 23:22

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