DTG/DTF and UV printers preferably operate at (60-80 F) room temperature. Operating the printer in temperatures below that mark, can cause a change in the consistency of the inks, as their thickness will start increasing.
Humidity is way more important - keep it between 45-60%.
If less than 42%, use a NON-MISTING humidifier
Why non mist humidifier ? water + electronics = short-circuit
In low humidity environment, ink will lose moisture and dry fast. Dry ink always provide poor prints. Dry ink will mess up the printhead. If ink dries into the printhead, it may not be recoverable.