2 stage boiler,2 100 dhw tanks, with barrel chiller, 2 pipe syst

scott h.

currently there is 2-300k btu boilers with a barrell chiller for cooling. two pipe system, fan coils in every room,(100 year old house,bed and breakfast) tekmar 261 controlling boiler. manual seasonal change over from summer to winter w/valves and power stoppage. Looking at putting in 2 100 gallon indirect dhw tanks, and they want mod boilers installed period. The boilers are only 5 years old at most, I think they should leave them be but it is refused and no longer a discussion. I am having trouble coming up with a control to handle all of this. the tekmar 265 will up to 3 mod boilers with dhw but i don't know how to do it in the summer with the chiller going. manual valve closing again? manual pump shut downs? I don't want this. I really am looking for a auto change over and still run the boilers for dhw in summer, not affecting the freeze protection or hot water lock out(cooling). tips would be great. I hope that it isn't too obvious and you guys take it easy on me. thanks

Don_197

Controls?

Hi,

You are stuck with the manual changeover UNLESS you get someone to design an autochangeover controller with electric valve actuators (not a big deal really.....maybe a little spendy) for you. I could do it if you provide me ALL points of control and monitoring......and most likely do it with off the shelf temp controls. As far as sequencing the boilers.....I HIGHLY recommend you go with the Lochinvar Knight. Each boiler has a built in cascading sequencer that can handle up to eight boilers and domestic hot water. Good Luck and let me know 8-)

Don Smet