Napoleon Arlington Gas Stove Blower Kit with Variable Speed and Thermostatic Control

Yes, this is the proper blower for the GDS20NNSB stove. 

Those instructions are located in the <a href="https://lib.store.yahoo.net/lib/yhst-95622685483394/npl-gds20nne-manual.pdf#_ga=2.253581261.531432785.1611584552-1042354391.1602855499"> owner's manual.</a>

This stove is only listed for use with a Napoleon stove, and it does not offer a size rating.

Yes, this blower is listed as compatible with the Napoleon GDS20 stoves.

The blower will definitely produce a noticeable hum while in operation, but the same may be said for most all blowers used in the hearth industry. This is simply the noise of air circulation and will increase or decrease, depending on the speed setting. More often than not, noisy blowers are the result of a lack of annual maintenance or being installed improperly. Due to the nature of hearth blowers, air is drawn in from floor level. This air will logically include any dust, lint or pet dander found around the hearth, but having a clean home is not a sufficient substitute for annual cleanings. Actually, customers who complain of noisy blowers and who also claim that the area around the hearth is kept clean will have more issues than customers who may have homes that are not so spotless because the act of cleaning will stir up dust, lint, etc., and this will be drawn into the blower housing.