thanks. it was the heater band indeed.
Using a spare one the temp reached 25C while the previous one was only 14C

Hello, My heater band is plugged on my UPB v2 PWM port with a RCA cable. The current consumption is measured 1.5 - 2 Amps (tried with 2 different bands and always at 100% of the output power). That seems ok to me but the band barely warms up. Recommended power for the band is ~12/16Watts (for a 140m...