PGH/AOS/M1 - Humidifier heater stopped working

The PID controller for the humidograph heater stopped working. The RH inside the wet neph 
stopped ramping up and down each hour and so there aren't any frh data for the fRH VAP.

• Aerosol total light scattering coefficient, Humidograph nephelometer green
  channel, 10 um particle diameter(Bs_G_Wet_10um_Neph3W_2)
• Aerosol total light scattering coefficient, humidograph nephelometer blue
  channel, 1 um particle diameter(Bs_B_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, humidograph
  nephelometer red channel, 10 um particle diameter(Bbs_R_Wet_10um_Neph3W_2)
• Aerosol total light scattering coefficient, Humidograph nephelometer green
  channel, 1 um particle diameter(Bs_G_Wet_1um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, Humidograph
  nephelometer blue channel, 1 um particle diameter(Bbs_B_Wet_1um_Neph3W_2)
• Temperature at wet nephelometer inlet(T_NephInlet_Wet)
• Aerosol backwards-hemispheric light scattering coefficient, blue channel, 10 um
  size cut, wet three wavelength nephelometer(Bbs_B_Wet_10um_Neph3W_2)
• Sample temperature inside humidified nephelometer(T_Neph_Wet)
• Pressure inside humidified nephelometer(P_Neph_Wet)
• Aerosol total light scattering coefficient, blue channel, 10 um size cut, wet
  three wavelength nephelometer(Bs_B_Wet_10um_Neph3W_2)
• Aerosol backwards-hemispheric light scattering coefficient, Humidograph
  nephelometer green channel, 10 um particle diameter(Bbs_G_Wet_10um_Neph3W_2)
• Relative humidity, Humidograph nephelometer(RH_Neph_Wet)
• Aerosol total light scattering coefficient, Humidograph nephelometer red
  channel, 10 um particle diameter(Bs_R_Wet_10um_Neph3W_2)
• Back-scattering coefficient, green wavelength, high RH, 1 um size cut(Bbs_G_Wet_1um_Neph3W_2)
• Back-scattering coefficient, red wavelength, high RH, 1 um size cut(Bbs_R_Wet_1um_Neph3W_2)
• Aerosol total light scattering coefficient, Humidograph nephelometer red
  channel, 1 um particle diameter(Bs_R_Wet_1um_Neph3W_2)