'77 Dometic Operating Install Manual RM46E
 

Operating and installation manual that came with an RM46E in a 1977 HiLo. There is a service manual on this site that may have more details about troubleshooting.

Thanks. My 1978 Hi-Lo came w/ the manual, but nice to have it electronically too. There is a more detailed "Diagnostics/Service Manual" (Scribd & ManualsLib), but just temp viewing, requiring a paid download. But, answered my questions about whether the cooling coils are working.

To summarize, if the burner tubes and "absorber" (to left of burner) are at about the same temperature, it is working correctly. If the absorber is much hotter, that indicates the H2 gas leaked out (not easy fix). If the absorber is much cooler, the system may be clogged. You see these coils when you remove the outside vents.

Sometimes the clogs are temporary, from fluid flowing into the wrong places. Turn off the heat for a day, with the refrigerator perfectly level. If the trailer sat un-level for a long time, it can get permanently clogged from the rust inhibitors settling out (may be fatal). That isn't a problem while moving since it gets shaken. These refrigerators are very fussy about sitting level. The cooling technology is ammonia absorption in an aqueous solution w/ hydrogen gas.