I am new to Partial Mash brewing and recently mashed my first batch of NB’s Surly Bitter Brewer kit. I just had a quick question regarding the temperature of my mash. I was using the lab thermometer that was included with my Deluxe Starter Kit and I am worried that my mash temperatures may have been a bit off due to the reported inaccuracies of this thermometer. However after my 90 minute boil my OG was about 1.042 with the kit giving an estimated OG of 1.040. So would this mean that my temps were ok if I achieved an accurate OG reading?