Setpoint Manager on the demand side of the hot water loop in DesignBuilder
Hello, I have a question about Detailed HVAC in DesignBuilder. Is it possible to add a Setpoint Manager-Outdoor Air Reset directly on the demand side of the hot water loop fed by a gas boiler, in order to control the water radiator supply temperature based on outdoor air temperature?
– In my system the HW Loop branches into multiple circuits, but I need to change the setpoint only for the node supplying the garage radiator without affecting the other loops.
– I’ve tried using EMS, but either the setpoint is overridden by a supply-side manager or the EMS has no effect on the demand side.
I’m attaching a schematic of my system. https://ibb.co/cKDmhKyj
How would this approach be reproduced in a real system? The temperature only for the radiator cannot be higher than the boiler temperature, and for it to be lower it would need to be mixed with cold water, which achieves the same result as lowering the water flow through the radiator.
The garage radiator must have a circulator pump and mixing valve. The mixing valve would have to be automated to modulate the loop temperature based on OA reset. Cold water is not required.
Thank you all for your replies. @Greg Estep I tried to implement this solution earlier, but it is not possible to add a mixing valve and pump without adding a buffer tank (as I did in the underfloor heating loop). As far as I know, real systems do not have this additional tank, so I wonder if it will not cause too much energy loss due to the efficiency of the tank and, in general, if it will not affect the system too much. Do you know of a way to connect the boiler loop with an auxiliary water loop with a mixing valve without adding a tank?