No, the boat is only runing weekends on a regular base, if at all in the current times. In fact I thought it was suspended already long time ago even weekends. Its mainly aimed at bringing visitors to some places and wats along the canal and not that much for Min=muslimburi and perhaps even NC. Youre far, far quicker there to go by various vans, f.e. from Vict.Monument or Mall/Bangkapi. In fact I also suppose on normal weekdays they need all the fleet they have to run the normal service.
How long do you live here? Never still noted that such things are never formal, just ask along the place and sooner or later someone will turn up and offer their services/boats/whatever. That is IF its nowadays even possible to do that. There may very well be dams/dikes/sluices/low bridges preventing it or needing to walk around them. Most likely the water will also be more waste dump as navigatable. But very often near/just off many of these so called ´floating markets´ there will be some boattrip on offer on the days it opens.