Adding a ASHP to residential model

asked 2024-01-08 18:04:15 -0600

ahahawhut

31 ●2

updated 2024-01-09 08:13:29 -0600

Aaron Boranian

14250 ●86 ●24 http://bigladdersoftware.com/

I am building a residential model in EnergyPlus in a heating dominant climate. The model currently has DX:SingleSpeed for cooling and Coil:Heating:Fuel for heating. I would like to change the HVAC such that it is now a ASHP (preferrably min-split ducted) with the furnace as a supplement during winter months.

I've looked up product specs to build out the performance curves using the axillary programs, but am unable to figure out the node and equipment placement with the furnace in a Blow Through position. I'm also consistently getting an error for not having a defrost curve, which I know is a known error, but cannot figure out how to build this curve to appease EnergyPlus.

Please provide some guidance to resources which may help.

tl;dr : looking for examples of HVAC diagrams with ASHP system (preferably min-split ducted) with furnace as supplement and/or resources to build defrost energy input ratio function.

answered 2024-01-11 16:56:15 -0600

shorowit

11961 ●203 ●9 https://www.nrel.gov/b...

Assuming the ducted mini-split and furnace are sharing the same distribution system and blower, you can model the mini-split using the AirLoopHVAC:UnitarySystem object (with MultiSpeed or VariableSpeed DX heating/cooling coils) and then describe the furnace using a Coil:Heating:Fuel that's assigned to the UnitarySystem's Supplemental Heating Coil. The supplemental coil will provide heating whenever the DX heating coil has insufficient capacity compared to the building's heating load.

You might also set the Minimum Outdoor Dry-Bulb Temperature for Compressor Operation field for the DX heating coil if the mini-split cannot operate below certain temperatures, in which case the supplemental coil will provide heating during those situations as well.

Here is an example IDF w/ this kind of setup:

https://drive.google.com/file/d/1Ezds...

edit flag offensive delete link

add a comment

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Adding a ASHP to residential model

1 Answer

Your Answer

Training Workshops

Careers

Question Tools

Stats

Adding a ASHP to residential model edit

1 Answer

Your Answer

Training Workshops

Careers

Question Tools

Stats

Adding a ASHP to residential model