co-ordinated systems

Alan_5

I have a hydronic system that bugs me !
The boiler control keeps a small loop of water hot.
The zone valves turn on a circulator pump when the temp drops.
This is fine in the dead of winter. BUT
Since the two systems are independant of each other, the boiler is keeping water hot even if nothing needs it. The circulator pump blindly pumps water into the loops without knowing if the temp is right. Added to that, there is a heat exchanger for the DHW that also blindly turns on a pump when the tank goes below the set pt.

I first noticed a problem when sometimes the hot water in the shower would go from hot to cool to hot again. The original hot from the tank, then the pump kicked in, the cool coming from cold water from the heat exchanger, then the boiler would kick in and the temp would rise again.

I am a computer systems developer and have some knowlege of process automation. This system bugs me !

I need
A logical AND of from the zone valves(on) and boiler thermometer(cold)to enable the boiler.
A logical AND from the boiler thermometer(hot) and the zone valve (on) to enable the zone pump.
A logical AND from the DHW tank (cold) and the boiler thermometer (hot) to enable the DWH pump.

What type of controls can I use to do this?

Any comments?

Thanks
Alan

prm_8

More Intelligent Controls

Alan

Look at tekmar controls. While they may not have one controller you can drop in, they do have an extensive line of intelligent controllers. www.tekmarcontrols.com.

Paul