TD2K has done the most reasonable estimate, except that the assumption of surface temperature may not apply to the four sides. In that case, since he already allowed that his estimate was "comfortably" on the high side, I submit that it's still trivial. Even if the case was several dryers concentrated in one spot, it may still be better to estimate the periodic opening/closing of the door. This was not that case, however - "dryer" was singular, not plural.
At something less than 400 Watts ("comfortable" allowance from TD2K's estimate), by the time you count the diversity (intermittent, infrequent operation), you really are at a trivial amount. In any event, the latent load is zero as well.
As for making the house noticeably warmer, some installations may have made mistakes - such as exposed duct runs or crawl space/basement/attic venting that can re-radiate back into the conditioned space. Or, in some cases, the dryer vent may dump onto the outdoor unit of the A/C system. Any of these may adversely affect space load.
The Carrier design books (several versions), ASHRAE Handbooks, and ASHRAE load manuals were checked before my first post. An estimate is not there - and is itself an indication of the load effect.