going to be getting coal boiler in another week (handfired). Going to do some replumbing of exsisting oil boiler(new watts AS-MB 1 1/4" seperator,watts B911 combo fill/BF valve,watts RBFF ResBoilFill Fitting) reposition the exspansion tank off the top of boiler to seperator unit where it should be, and put a pressure gage just above exspansion tank between it and the RBFF valve.
i am going to put duplicate setup on the coal boiler for water supply,backflow and airtrap/expansion. the 2 units will be in seperate parts of house, looking for a pump to run at a low speed continually to keep water circulating between the 2 units to maintain constant temp, and when there is a demand for heat to run pump at a higher GPM flow.
Zones are individual taco pumps, honeywell R845A controlled, zone calls for heat it turns on pump, and draws off common manifold for supply side off boiler, return from zone go to common return manifold then to boiler.
So my hooking up to exsisiting boiler will be rather easy using the common manifolds, and some valves, and "T" and 90's fittings in return/supply side feeds before commonon manifolds.
question is????.....is the duplication of cold feed,exspansion stuff appropiate? and who knows of a pump with a continual low flow/speed variable motor and what contoller to use for the 4 inputs from taco pump controllers?
Coal boiler will still be independent of oil furnce controls for its aquastat/draft controls.