Ironbug ASHP w/ Boiler Backup

I am looking to model a ASHP as the plant loop that provides heating and cooling to the terminal unit coils. When the O/A temp drops below a certain temperature then a backup gas boiler would take the heating load.

I found this old post:
Hybrid system (heat pump and gas boiler) - grasshopper / honeybee - Ladybug Tools | Forum

@mingbo can this be modelled using ironbug? Is there any similar examples?

Tagging @mingbo here so it doesn’t get lost

This is what I would do to control the backup boiler:
You can try to use AvailabilityManager:HightTemperatureTurnOff for the backup boiler’s control, and set the temperature along with the sensor node set to the OA inlet node.

I have not tested this, but this should give you an idea.


Hi @marentette

I have just finished adding all Availability Managers to Ironbug. (You need to download the latest version of Ironbug from here)

Here is a sample Availability Manager with (13.6 KB) that includes an AvailabilityManagerHighTemperatureTurnOff that turns off the system based on the outdoor air temperature. (note this is not a simulatable airloop, but just giving you an idea how an availability manager works with a sensor probe)