2000 Silverado 1500 heater control valve

kwed2011 · October 15, 2018

Hi All,

After a cold front overnight today was my 1st opportunity to use the heater this season. Unfortunately no warm air came out of the heater regardless of the dial position. I checked both heater hoses under the hood & they are not hot. I believe my heater control valve is stuck/broken. Does anyone have experience replacing these on a 2000 Silverado 1500 5.3L. I checked Youtube but could not find a good video for this truck. There was one for a 96 truck but the valve is not in the same location. I'm sure I can figure it out but if anyone can give any tips, I'd really appreciate it.

Thanks

carkhz316 · October 16, 2018

These trucks don't utilize a heater control valve like others do. If your truck is up to operating temp, but both heater hoses are not hot, then it would seem there is little to no flow to/ through the heater core. Is one (inlet) slightly warmer though? If so, then your core is plugged.

kwed2011 · October 16, 2018

Hi carkhz316, thanks for the reply. Yes. The hose closest to the to the engine is warmer than the other. Is it possible to run water through the heater core in the opposite direction to unclog it?

sefiroxx · October 16, 2018

Yes, disconnect hoses and try to clear out simple clogs first. Then hook up hoses reversed and run for an while.

kwed2011 · October 16, 2018

Hi sefiroxx, Thanks. That worked like a champ. with a warmed up engine, pressurized radiator I clamped the heater feed hose & disconnected it from the heater core. The pressure in the system pushed coolant through the heater core in the reverse direction. I then switched both hoses so it now flows the other way. The heater is working great now. Will it cause any problems to leave the hoses like this flowing the other way? I wouldn't think it really matters.

Thanks