The former Reading keeper beat away Danny Drinkwater's blistering close-range drive and was then quick up on to his feet to turn away Lee Novak's follow-up header.
It helped secure a first point on the road for the Pirates since a 3-2 win at Southampton in September. The double save came after 20 minutes and it took another hour for a lacklustre home side to seriously threaten Andersen's goal.
Robbie Williams laid off a free-kick to Peter Clarke and the Huddersfield skipper drilled a 20-yard drive which Andersen did well to tip round the post.
Chris Lines nearly won it for Rovers after 84 minutes with a shot from a tight angle which Huddersfield keeper Alex Smithies tipped onto the post and former MK Dons midfielder Mark Wright also went close at the end of a poor first half.
Wright beat the offside trap and fired a shot at Smithies which looped off the keeper towards the Huddersfield goal but was cleared off the line by Town's Antony Kay.