Smart thermostat schedule logic template

Components in this architecture diagram

• Every minute
• Read schedule setpoint for time of day
• Manual hold active?
• Use hold setpoint until expiry
• Home occupied per sensors or phone geofence?
• Switch to eco away setpoint
• Use scheduled comfort setpoint
• Utility demand response event?
• Pre-cool or pre-heat then offset setpoint
• Keep setpoint
• Read room & remote sensor temperatures
• Check outdoor weather forecast
• Temperature outside deadband?
• Idle HVAC
• Heat or cool?
• Run furnace or heat pump
• Run air conditioner
• Log runtime to app energy report
• Wait for next cycle

How to use this architecture diagram template

1. Click Open in the editor. The architecture diagram opens on a new page in FlowDiagram — nothing is uploaded and there is no sign-up.
2. Rename, add or delete shapes and drag them where you want; connectors stay attached as things move.
3. Drop in vendor logos from the library — 1,160 of them, including every AWS, Azure and Google Cloud service icon — or restyle it with the colour and theme controls.
4. Prefer text? Edit the Mermaid source below and paste it in through ☰ → Import diagram (see the Mermaid editor); it imports as an editable diagram.
5. Export to PNG, SVG or PDF, or press Ctrl+L for a link that carries the whole diagram.

Mermaid source

The whole template is the text below. Paste it into FlowDiagram, keep it in Git next to the code it describes, or hand it to an AI assistant to extend.

flowchart TD
  A((Every minute)) --> B[Read schedule setpoint for time of day]
  B --> C{Manual hold active?}
  C -->|Yes| D[Use hold setpoint until expiry]
  C -->|No| E{Home occupied per sensors or phone geofence?}
  E -->|No| F[Switch to eco away setpoint]
  E -->|Yes| G[Use scheduled comfort setpoint]
  D --> H{Utility demand response event?}
  F --> H
  G --> H
  H -->|Yes| I[Pre-cool or pre-heat then offset setpoint]
  H -->|No| J[Keep setpoint]
  I --> K[Read room & remote sensor temperatures]
  J --> K
  K --> L[Check outdoor weather forecast]
  L --> M{Temperature outside deadband?}
  M -->|No| N[Idle HVAC]
  M -->|Yes| O{Heat or cool?}
  O -->|Heat| P[Run furnace or heat pump]
  O -->|Cool| Q[Run air conditioner]
  P --> R[Log runtime to app energy report]
  Q --> R
  N --> R
  R --> S((Wait for next cycle))

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