laars mini therm 2 zone gas fired boiler

[crugj1]

I have a laars mini therm gas fired boiler with 2 zones. Question: when it calls for heat, the gas always turns on, is there a way to have the circulator pump continue to run when it calls for heat without the gas flame on when the water temperature is 150-170 degrees F?
it seems like a waste of money to have the gas heating the water when its hot enough to heat hosue?? thanks

 

[Fitter30]

Is long as you keep the return water temp over 130° its in the manual. I use 140° so if it dips down there is some room just in case. Cast iron boilers don't like the water temp because of shocking it and condensation in the flue and cast fire block surrounding the burner. If boiler is in a basement that beat isn't lost it's going into the house.