Danfoss BD35 and BD 50 compressors have variable speed capability and can run at speeds between 2,000 and 3,500 RPM. The longer and slower these compressors run, the more efficient they get, so it makes good sense to exploit this feature. Fixed Speed can be obtained by installing resistors into the thermostat circuit. With no resistor installed, the compressor will operate at the lowest speed, 2,000 RPM. Manually Adjusted Speed - Speed Board. Additional circuit board that plugs on to the controller (module). Has rotary adjustment to select speeds from 2,000 to 3,500 RPM. Guardian system controller. Remote panel that has Coastal MK II digital thermostat, diagnostic LED, and compressor speed selection knob. Merlin Smart Speed Controller. Additional circuit board that plugs on to the controller (module). Gives fully automatic speed control plus cold-start ramp-up routine. LED shows compressor run speed. Can be used with Guardian for the ultimate control package.
Click image for explanation of compressor speed control
Click to buy Merlin Smart Speed Controller
Merlin Smart Speed Controller
Circuit board that plugs on to Danfoss controller (module). Gives automatic variable speed for higher efficiency, plus warm-start ramp-up sequence for protection of electronics. Status LED flashes speed of compressor when running; steady glow when compressor idle. Plug-and-Play installation. No tools required.
Click to buy Guardian System Controller
Guardian Replaces SSC. Small Panel, approx. 5" x 2". Features Coastal MK II Digital Thermostat/Thermometer plus auto/manual speed selection knob and diagnostic fault LED. When used with the Merlin Smart Speed Controller, gives automatic speed control. TheGuardian is pre-wired with a 10' harness and slip on connectors to facilitate a quick and easy installation.
Click to buy Frigoboat speed selection board
Speed Board This is a secondary circuit board that is mounted with female connectors on to the Danfoss 101N0210 Controller. Compressor speed is adjustable from 2,000 RPM to 3,500 RPM with small screwdriver.
NOTE: Controller not included.
Coastal Climate Control, Inc. Annapolis MD USA 301-352-5738