You can't heat a rack with RHP easily, min set up distance for most manufacturers is 18-22 inches that from the face say the panel is 2 inches thick that means each level would need to be 20-24 tall they cannot be safely used horizontally mounted they are 'safe' from CONTACT burns because snakes cannot touch the surface. A 40w RB panel on max will hit 190º too hot for anything other than over head. I know Dr. Del here suggests caging all RHPs in any set up.
Only one RHP per thermostat, they heat objects not air and like the sun the colour and reflective qualities of the object being heated change the amount they heat the object. There are far too many variables to use them safely in this type of set up. Add that they have a carbon heat tape as a heat source inside them, you still are using flexwatt.
I also would question the use of an on/off tstat with RHP, many manufacturers recommend a proportional controller. The way the panels deliver heat is not well suited to the extremes of an off on system there is no buffer against hysteresis, swing, or backlash that all on off have to some degree.
Add that the RHP does not easily build a horizontal gradient but rather a vertical one it has no business in a rack, period. I would suggest it to be unsafe in this application. I am not a huge fan of flexwatt or self wired heat tapes in general. I understand the concern and I would suggest a low wattage low density UTH as the max. safest. (Kane is likely the most robust and runs in the range of RHPs, Ultratherm, intelliheat, there are others any that is designed not to exceed 100ºF) Used with a proportional control and a secondary back up there is little to go wrong especially if on every deep cleaning they are closely inspected. They are as safe as any heater if used according to the manufacturers recommendations.
Reply With Quote