CoolAutomation CoolMaster

Local TCP integration for the CoolAutomation CoolMaster family — CoolMasterNet and the larger CoolMaster Pro. These boxes are universal VRF/VRV-to-IP gateways: they sit on a manufacturer's indoor-unit bus (Daikin, Samsung, Mitsubishi Electric/Heavy, Toshiba, Hitachi, LG, Panasonic, and more) and expose every indoor unit over a single ASCII "line" protocol on TCP 10102.

One CoolMaster becomes one GEM device row; each indoor air handler becomes a climate zone addressed by its CoolMaster UID (for example L7.400 — line 7, address 400).

What this integration covers

• Power — on / off per indoor unit.
• Mode — cool, heat, auto, dry, fan (mapped to GEM system_mode; off powers the unit down).
• Setpoint — single target temperature per unit, reported and set in °F.
• Fan speed — low, medium, high, very_strong (CoolMaster "Top"/turbo), auto.
• Swing — auto / vertical / horizontal / off, where the indoor unit supports it.
• Status polling of on/off state, mode, room temperature, setpoint, fan speed, the unit fault code, and the active heating/cooling demand flag.
• Auto-discovery — the driver enumerates indoor units with ls and (by default) creates a climate zone per unit.

What this integration does NOT cover (yet)

• Push updates. The CoolMaster line protocol is strictly request/response with no unsolicited event stream, so a change made at a wall controller appears at the next poll (within poll_interval), not instantly.
• Dual heat/cool setpoints. A CoolMaster indoor unit has a single setpoint; the setpoint command accepts a mode argument for climate-UI compatibility but always applies that one setpoint.
• Line / DIP configuration. Assigning an HVAC line to a manufacturer (Daikin, Samsung, …) is done on the box — by DIP switches for lines L1/L2 and on-device for L3–L8. The driver consumes whatever lines are already configured.
• PRO-only object data (ostat/istat outdoor and indoor "PRO" telemetry), filter-life resets, group management, and the box's other gateway roles (Modbus, BACnet, KNX, REST). The driver speaks only the indoor-unit control surface.

Prerequisites

• A CoolMaster reachable from the GEM host on TCP 10102 (the "ASCII server" / aserver port). Confirm it is enabled on the box.
• HVAC lines already configured on the CoolMaster with indoor units detected (verify with ls / line on the device console).

Setup steps

1. In GEM, go to System → Devices → Add Device (Open Devices) and pick CoolAutomation CoolMaster as the driver.
2. Enter the device ip and port (default 10102).
3. Save. After a few seconds the device row should show Connected — the driver reads the box's °C/°F setting and identity, then polls ls.
4. Run the discover command to list the indoor units the CoolMaster currently reports (UID, mode, setpoint, temperature).
5. Leave auto_create_zones on (the default) to have a climate zone created per indoor unit, or set it off and create zones by hand with address = the CoolMaster UID (e.g. L7.400).

Subsystem placement

Auto-created zones are placed under the seeded Climate subsystem. If your site has no climate subsystem the driver logs a warning and skips creation — create the zones manually (any subsystem works; the subsystem only affects grouping/presentation, not whether commands work).

Attribute reference

Device attributes

Name	Type	Required	Description
ip	string	yes	LAN IP or hostname of the CoolMaster.
port	int	no	ASCII server port (default 10102). A blank or out-of-range value uses 10102.
poll_interval	int	no	How often to poll all indoor units with ls, in ms (default 15000). The poll runs at most once a second; zero, negative or unreadable values use the default.
auto_create_zones	bool	no	Create a climate zone per discovered indoor unit (default true).
firmware	string	—	Read from the box (version).
model / serial	string	—	Read from the box (S/N).

Zone attributes

Name	Type	Description
address	string	CoolMaster unit UID, e.g. L7.400 (required).
state	string	on / off.
system_mode	string	off when the unit is off, otherwise cool / heat / auto / dry / fan.
device_mode	string	The underlying mode regardless of power — used for an optimistic power-on.
setpoint	int	Target temperature in °F.
temperature	int	Current room temperature in °F.
fan_mode	string	auto / low / medium / high / very_strong.
system_modes / fan_modes	json	Capability lists published once so the climate UI renders the right buttons.
min / max	int	Setpoint bounds seeded once by the driver: 60–90 °F, in °F like the setpoint, whatever unit the box displays. Older versions seeded 16 / 32 on a °C box, which capped the setpoint at 32 °F; if a zone still shows those values, set them to 60 / 90.
fault	string	The CoolMaster fail-code for the unit; empty when OK.
demand	bool	true while the unit is actively calling for heating/cooling.
swing	string	Last swing value applied.

Commands

Command	Args	Notes
on / off	address	Power the unit. on resumes its last mode.
system_mode	address, mode	off, cool, heat, auto, dry, fan. Any non-off mode also powers the unit on (a CoolMaster mode verb does not power on by itself).
fan_mode	address, mode	auto, low, medium, high, very_strong (= "Top"/turbo).
setpoint	address, setpoint, mode	Target temperature in °F. mode is accepted for UI compatibility but the unit has a single setpoint.
swing	address, mode	auto, vertical, horizontal, off, where supported.
get_temperature / get_system_mode / get_fan_mode	address	Return the last-polled value for the zone.
discover	—	List all indoor units the box currently reports.

How state mapping works

• Temperature units. GEM works in °F. The CoolMaster has one display unit (°C or °F); each ls temperature carries a C/F suffix and the driver also reads the unit from the box's set reply. Reads are converted to °F; setpoints are converted back to the device unit before sending. On a °F box this is a no-op.
• Off vs. mode. The climate UI treats "off" as a mode, so when a unit is off the driver reports system_mode = off while preserving the real cool/heat selection in device_mode. Turning the unit back on optimistically restores device_mode, and the next poll reconciles.
• Polling. Every ls reply line is parsed independently and keyed by UID, so one poll refreshes every zone. Duplicate UIDs (only possible with the device's simul test mode) collapse onto a single zone. A zone whose address was typed in lower case (l7.400) is matched to the unit the box reports as L7.400.
• Commands. A command answers an error, and leaves the zone's state alone, when the line could not be sent (the box is disconnected). Otherwise the zone is updated straight away and the next poll confirms it.
• Connection health. Once the box has answered on a connection, three polls in a row with no reply (at least 45 seconds) close the connection and the driver reconnects. Without this, a box that lost power could leave the device showing Connected with every zone frozen at its last values.

Troubleshooting

Symptom	Check
discover returns no units but the device connects	The HVAC line may be configured but have no indoor units detected on the bus. Run ls / line on the CoolMaster directly.
Setpoint lands a degree or two off	The box is likely in °C while GEM works in °F; the driver rounds on conversion. Confirm the device unit with the set command.
A zone shows a fault value	The CoolMaster reports a non-OK fail-code for that indoor unit — check the unit's error code on the equipment.
Zone state lags a manual change at a wall controller	Expected — there is no push; state refreshes on poll_interval.
The device drops to disconnected and reconnects on its own	The box stopped answering polls for three intervals. Check its power and network link; the log line coolmaster: no reply to polls, recycling socket marks each occurrence.
A unit never gets a zone and the log mentions a zone insert error	The zone could not be created (for example its name is taken). The driver waits 10 minutes before trying that unit again; create the zone by hand with the unit's UID as address.