> For the complete documentation index, see [llms.txt](https://docs.ladybug.tools/hb-energy-primer/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ladybug.tools/hb-energy-primer/components/4_hvac/shw_system.md). # SHW System ![](/files/iwlNTpNG883G4vFQW0sO) ![](/files/YzuU76JETc4LeDLep3Wx) - [\[source code\]](https://github.com/ladybug-tools/honeybee-grasshopper-energy/blob/master/honeybee_grasshopper_energy/src//HB%20SHW%20System.py) Apply a template Service Hot Water (SHW) system to Honeybee Rooms. Note that the rooms must have hot water loads assigned to them in order for them to be connected to the system. ### Inputs * **rooms \[Required]** Honeybee Rooms to which the input template system will be assigned. This can also be a Honeybee Model for which all Rooms will be assigned the SHW system. * **system\_type \[Required]** Text for the specific type of service hot water system and equipment. The "HB SHW Templates" component has a full list of the supported system templates. * **name** Text to set the name for the Service Hot Water system and to be incorporated into unique system identifier. If the name is not provided, a random name will be assigned. * **efficiency** A number for the efficiency of the heater within the system. For Gas systems, this is the efficiency of the burner. For HeatPump systems, this is the rated COP of the system. For electric systems, this should usually be set to 1. If unspecified this value will automatically be set based on the equipment\_type. See below for the default value for each equipment type: ``` * Gas_WaterHeater - 0.8 * Electric_WaterHeater - 1.0 * HeatPump_WaterHeater - 3.5 * Gas_TanklessHeater - 0.8 * Electric_TanklessHeater - 1.0 ``` * **condition** A number for the ambient temperature in which the hot water tank is located \[C]. This can also be a Room in which the tank is located. (Default: 22). * **loss\_coeff** A number for the loss of heat from the water heater tank to the surrounding ambient conditions \[W/K]. (Default: 6 W/K). ### Outputs * **report** Reports, errors, warnings, etc. * **rooms** The input Rooms with a Service Hot Water system applied. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.ladybug.tools/hb-energy-primer/components/4_hvac/shw_system.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.