I am stumped on this one, sorry for long background required:
Currently installing Lennox Brentwood fireplace (zero clearance high efficiency with fan blower kit to move air)
I purchased the factory blower (UZY5) which comes equipped with a molded plug and SJT cord, here is the documentation for the fan (minus instructions on plugging it into a receptacle that is pre-wired into the fireplace - very helpful):
The fireplace has a handy box within the bottom of the unit with the one and only electrical KO into the fireplace from the outside of the unit into this box. I was hoping to use a P&S DDH16P fan control to vary the motor speed (since Lennox has been unable to provide their blower control for 6 months and counting):
My original thought was to have the DDH16P control a receptacle mounted in the fireplace junction box, which is designed to accept a receptacle for plugging in the molded plug-equipped blower. However, I believe it is not to code to control a receptacle with a dimmer (and I assume a fan control as well). So, I figure that I could have the receptacle receive direct power and insert the fan speed control in the loop where the factory dimmer is supposed to go (see sketch above)...except there is only the one KO into the bottom of the fireplace and that goes into the handy box (where the receptacle will be). And yes, the factory blower control unit (VRUW) is also a wall mounted unit - so its control wires are supposed to get inside somehow other than through the louvers in the front of the unit.
Possible options seem to be:
1) Can the fan speed controller control the receptacle (maybe there is an exemption for a receptacle installed within an appliance)?
I know that Lutron has these:
but I do not like the lutron controls and the receptacle is listed on for Lutron dimmers and I would have to cut the plug off of my blower and the plug is only 2 prong - it's really just for lights, I think?
2) Can the blower be hard wired into the junction box and control with the fan control (this means cutting off the plug and using a strain-relief bushing into the cover of the handy box)? Not sure I can install a cord in this way, either...
3) Can a second wire be routed into the fireplace, either by putting two NM 14-2 through a single bushing and out the side of the handy box that will have a receptacle installed in it (don't think so), or by drilling another hole in the fireplace? (for the record, their tech support indicated they thought there were additional knockouts in the fireplace - there aren't anymore than the one)
This is a permitted job and I will be talking to the electrical inspector prior to starting the electrical (I just want to know what I am talking about/proposing).