06 t600 heater shut off value

He night of had a bad hose and shut it off. To find the valves follow the the hoses that come out of the cab and under the sleeper.hope this helps

 

look for 2 valves on the passenger side of the engine. with hoses that run to the cab like mentioned above.
1 valve is for the sleeper and the other valve is for the cab heater.

feel the temperature of the hoses. if they are hot. the valves are open. cold means closed valves.

 

there isn't any shut off valves. only a black plastic electrical valve under the heater box where the lines go into the cab. its either that, or the temp. control knob in the cab .

 

you've got 4 hoses. 2 of them don't have valves?????

you can tell if it's a bad core. 2 hoses. if both are hot. the core is plugged.
the core acts like a radiator. water going in will be much hotter then water going out. there should be a huge different in temperature between the 2 hoses.