Vulcan-Hart GRS25 Service Manual page 53

19. If servicing a D or C model with a 5/16" wrench remove the hi limit packing nut. For S models use a 1/2"
wrench. (Fig. 81)
20. With an 11/16" wrench remove the compression nut securing the limit bulb to the tank. (Fig. 82)
Fig. 81
Fig. 82
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