Respironics Humidifier not conducting heat

[Headintheclouds]

Wonder if anyone can help: my Respironics Humidifier was working fine last winter. I disconnected it in the summer months and now something is not quite right when i reconnect: The heating plate within the humidifier is working fine (it's hot to the touch when turned on), but the plate on the water chamber doesn't seem to be conducting the heat (not even luke warm after being in contact for hours). The two plates are touching I'm sure. The air that comes out is not warm and none of the water in the chamber is evaporated in the morning. Why is this happening? Seems to be defying physics.

[Pugsy]

What has your ambient humidity been lately?
Has it been raining much?
What is your humidity setting?

[Headintheclouds]

hi - I live in London UK and it's generally been quite dry indoors with the heating on