The SW syringe warmers will heat  DN-Series syringes but not as quickly as with a regular syringe. 
 
Recall that the DN-Series syringes have two syringes, each holding solution. While these two solutions are connected it will take some time for heat to communicate into the inner syringe
 
Many researchers pre-heat their solutions before loading them onto syringes mounted in pre-heated SW units.  This relieves the system from the effort to warm the solutions and increases their efficiency in maintaining the set temperature.