Modulate the Thermostat

Normal sudoku rules apply: every row, column, and box must contain a complete set of the digits 1-9.

Thermometers: Digits on thermometers must increase from bulb to tip, not necessarily consecutively. Each thermometer is also a modular line running from bulb to tip.

Modular lines: every set of three sequential digits along a modular line must contain a complete set of residues modulo 3, i.e. one digit from {1,4,7}, one from {2,5,8}, and one from {3,6,9}.

Thermometers extending from the same bulb are distinct modular lines; that is, modular lines do not necessarily cross over bulbs from one thermometer to the next.