Here is the Cen-Tec nozzle that you have mentioned you are looking to get. Both power nozzles are very similar. I'm fairly certain they are the same motor. Both use Serpentine belt, both have same 14" double brushed wooden Chevron agitator. Both have bristle up to both edge of nozzle- double edge cleaning. Note that neither one has a suction duct extending around the belt area to reach the far side of the nozzle. Dirt swept in that area has no where to go, a flaw that greatly angers me about CenTec nozzles. Both nozzles have the same carpet height adjustment and motor protection shutoff. I've noticed with these nozzles that if something gets stuck in them it takes the sensor a good bit to react and shut down the nozzle, generally it's faster if I have turn the machine off myself.
The CT18DXQD in above posting has plastic rear wheels, straight nozzle design, slightly higher profile in rear. In servicing there is a separate nozzle area cover to be removed, after taking off top cover.
Pictured here is CenTec CT20DXQD. Rubber rear wheels, which according to some consumers, they've had experience with rear wheels coming off axle, lower profile from many other nozzles. Very bright headlight. You will notice it lighting up the cieling greatly. T shaped nozzles will fit around some chair legs and some other obstacles a little.
Many repair shops like both nozzles. I've heard some argue that the belt on Cen-Tecs is too narrow to really distribute power. My argument is of the suction dection. Overall cleaning performance is good on both, chevron agitator is good, but bristles aren't very long so I imagine they may wear quickly. Motors are very powerful and quiet, and built for many years of use.
Best of luck, let me know if there is anything else I can help with. Try plugging in the machine without hose connected, I'd be curious if it turns on or not. You can see what others or a vac shop may recommend but I wouldn't worry too much about cleaning the hose as I think you will need to replace it in-order for the machine to shut off.
http://www.centeccommercialvacuums.com/commercial-cleaning-items/CT20DXQD
