Altherma HT, read on its outdoor unit: the HT's leaving and return water are on its outdoor unit (ERRQ/ERSQ, X41A on A1P), in a block the unit only answers when asked with the hydrobox's address. ESPAltherma now reads that address and asks that way, and the new definition "Altherma(HT ERRQ-ERSQ outdoor unit 11-16kW)" gives the water, the outdoor air, the R410A stage and the hydrobox's state and error. It is recognised by the shape of its replies (it was taken for the hydrobox before). Map by @selman61 (#95), checked on @PiotrBeeScale's ERRQ016AAV1 (#599). The drawing shows the compressor when the unit reports it in Hz.
Diagnostics → Memory read: reads bytes of the hydro board's memory, nothing written, for the people mapping a unit (the Altherma 4's upper tank sensor, #523).
MQTT: the keepalive is 60 s instead of 15, so a broker that answers late no longer costs the connection, and a stall of the board's main loop over 5 s now writes a line in the event history with where it was stuck.
Fix: "Run the survey again" (Diagnostics) no longer throws away a model chosen by hand; "Detect again" on the model page still detects from scratch.
Home Assistant card v1.0.22: the HT outdoor unit's water and the compressor in Hz.