How much does ambient temperature affect the indication given by strip heaters?
I ask because with my fermenter in an insulated box it reads 22 deg C, outside (ambient of 14 deg C) it is reading 18 deg C. I have an immersion heater inside the fermenter.
On a related topic, I can buy a variety of inexpensive digital thermometers at my local electronics store, the inside/outside style have a lead and a remote temperature probe. These seem to be made of PVC and I had some doubts about putting PVC in contact with the wort. Any tips?
cheers