This is a 2-part question, please, appreciate any help you can provide -
I had a Keystoker K6 installed late last winter, and it is wired into my 3 existing zone thermostats rather than on a separate thermostat. This allows for optimum zone heat control, as with a regular gas boiler. The problem is the gas boiler still wants to keep the water to the temperature on the gas boiler aquastat. This isn't a savings, obviously. I turned the BTU's down to 150 on the gas boiler aquastat and it still wanted to fire, not sure why. This is an old gas boiler.
Question 1 -
The gas boiler has a "main" gas line and a separate gas line to the pilot.
So I'm wondering as the season approaches if I can simply turn off this main gas line to the gas boiler (as I do in the summer) to keep the gas boiler from wanting to heat the water and take advantage of having the 3 zone heat control?
Question 2 -
I know it is typical to have the coal boiler on a separate thermostat that is set slightly higher than the gas boiler thermostat so if the coal fire goes out the gas boiler will come on.
How often do coal boilers go out or shut down? If there's a power loss the gas boiler will be out of commission as well, won't it?
Is the current installation using the existing zone thermostats ill-advised for any other reasons? I don't plan on leaving the coal boiler on when away from home for more than a day or two, and will turn on the gas boiler in those cases.
Thank you for your comments and your help. This will be my first year using coal and this site has already been invaluable. I know I will learn much more here as the season begins.