The controller should work with all Mitsubishi Lossnay ERVs. This has been used for more than an year now and no issues were observed.
The functionality includes: 1) Turning on and off the device. 2) Setting the fan speed to 1, 2, 3 or 4. 3) Switching between Lossnay and bypass mode. 4) Monitoring the ERV diagnostic output (operating, bypass/lossnay, error). 5) Tracking two BME280 sensors for monitoring the supply and exhaust air temperature and humidity. 6) API for exposing the current status (http://{...}/get). 7) Telemetry collection and publishing to a local InfluxDB instance.
The PCB project is available at EasyEDA's OSHWLab. From there you can directly order the PCB at JLCPCB.
| Designator | Name | Footprint | Quantity |
|---|---|---|---|
| C1,C2,C8 | 100nF | C0603 | 3 |
| C6 | 10nF | C0603 | 1 |
| C7 | 3.9nF | C0603 | 1 |
| C9 | 10uF | C1206 | 1 |
| C10 | 22uF | C1206 | 1 |
| CN17 | jst xhp-5 | JST_XH2.54_5P | 1 |
| CN26_BPS,TM2 | Taster_H | JST_XH2.54_2P | 2 |
| D6 | SS26 | SMA | 1 |
| I2C,MONITOR | jst xhp-4 | JST_XH2.54_4P | 2 |
| L1 | 100uH | IND-SMD_L7.3-W7.3 | 1 |
| L2 | 100uH | CD32 | 1 |
| P2 | DG308-2.54 | DG308-2.54-6P | 1 |
| R1,R2,R3,R4,R5,R6 | 430 | R0603 | 6 |
| R7,R8 | 4.7k | R0603 | 2 |
| R9 | 6.8K | R0603 | 1 |
| R10 | 100K | R0603 | 1 |
| R11 | 1k | R0603 | 1 |
| R12 | 2k | R0603 | 1 |
| R13 | 4k | R0603 | 1 |
| R14 | 560 | R0603 | 1 |
| R16 | 26.1K | R0603 | 1 |
| R18 | 10K | R0603 | 1 |
| R31 | 4.7k | R0603 | 1 |
| R32 | 120 | R0603 | 1 |
| U1,U2,U3,U4,U5,U10 | VO1400AEF | SOP-4 | 6 |
| U7 | WEMOS D1 MINI | WEMOS D1 MINI | 1 |
| U8 | MP2307DN-LF-Z | SOP-8 | 1 |
| U9 | MAX3485 | SOIC-8 | 1 |
The supply voltage should be between 5V and 24V.
The RS485 part is not yet implemented in the firmware and can be skipped. This will likely be added in future versions of the firmware.
If there are WiFi connectivity issues swap the WeMos D1 Mini for a D1 Mini Pro with the same module size. The pro has a ceramic antena and SMA connector for external antena.
This is based on the official documentation provided by Mitshubishi. Download the "Lossnay Energy Recovery Ventilator Installation Instructions" (the file is usually named LGH-RVX_Installation_Manual.pdf) and crosscheck each connection point.
Based on "When interlocked with indoor unit of air conditioner or other external device including other manufactures." from the documentation, 3rd option - "When the external device has an uncharged a-contact signal".
The device must be turned on before operating it. Untill it is turned on - the speed settings have no effect. This is acomplished by one of the SSRs that connects TM2-1 to TM2-3.
| The wiring diagram is: | Controller | Lossnay |
|---|---|---|
| TM2-1 | TM2-1 | |
| TM2-2 | TM2-2 |
Based on the "When switching fan speed externally" from the documentation.
This works by using the CN17 connector. There are 4 SSRs that are connecting one of the CN17-2/CN17-3/CN17-4/CN17-5 to CN17-1.
| The wiring diagram is: | Controller | Lossnay |
|---|---|---|
| CN17-1 | CN17-1 | |
| CN17-2 | CN17-2 | |
| CN17-3 | CN17-3 | |
| CN17-4 | CN17-4 | |
| CN17-5 | CN17-5 |
Based on the "When switching By-pass externally." from the documentation.
In some cases it would be desired to use the bypass mode to avoid heat/humidity recovery. Again achived by SSR connecting CN26-1 to CN26-2. Connecting these two will force bypass mode. Disconnecting them will set the desired mode to recovery (lossnay) mode. The HRV may decide by itself to enter bypass mode in some cases. Check the documentation for details.
| The wiring diagram is (Controller <-> Lossnay): | Controller | Lossnay |
|---|---|---|
| CN26_BPS-1 | CN26-1 | |
| CN26_BPS-2 | CN26-2 |
Based on the following 3 sections from the official documentation:
The Lossnay exposes 3 relay outputs indicating if the device is on or off, if there is a malfunction and the current mode (lossnay/bypass). The controller monitor these through the analog input and array of 3 resistors.
| The wiring diagram is (Controller <-> Lossnay): | Controller | Lossnay |
|---|---|---|
| MONITOR-1 | TM3-7 | |
| MONITOR-2 | TM3-8 | |
| MONITOR-3 | TM3-9 | |
| MONITOR-4 | TM3-10 |
The project uses a common set of tools that are availabe in another repo - https://github.com/funnybrum/esp8266-base. Clone the esp8266-base repo in the lib folder:
cd lib
git clone git@github.com:funnybrum/esp8266-base.gitOn first start the device will create an open WiFi network named ventilator. Connect to it and open http://192.168.0.1. This will bring the configuration page. Set the host name, the SSID and the password. Click "Save" and "Restart". The device will reboot, connect to the WiFi network and will be accessbile by its hostname.
The configuration page will be available all the time. Go the http://{hostname or IP address}/ and you will get redirected to the same page that you used for the first boot.
This will expose a JSON document similar to the following one, but without the comments:
{
"ra_temp": 20.6, -> return/exhaust air temperature, in C
"ra_humidity": 49.9, -> return/exhaust air relative humidity, in %
"ra_pressure": 922, -> retur/exhaust air pressure, in mbar
"ra_abs_humidity": 8.94, -> retur/exhaust air absolute humidity, in g/m3
"sa_temp": 19.4, -> supply/fresh air tempeature
"sa_humidity": 46.9, -> supply/fresh air humidity
"sa_pressure": 922, -> supplyfresh air pressure
"sa_abs_humidity": 7.82, -> supply/fresh air absolute humidity
"bypass": false, -> current desired mode (the one set by the controller)
"power": true, -> Lossnay desired power status
"fan_speed": 1, -> Lossnay fan speed
"analog": 965, -> Current status on the analog input, for debuging purposes
"i_bypass": 0, -> Lossnay bypass status as reported by the Lossnay itself
"i_malfunction": 0, -> Lossnay error/malfunction indiciator as reported by the Lossnay itself
"i_operating": 1, -> Lossnay operating status as reported by the Lossnay itself
"rssi": -73 -> WiFi RSSI
}```