Originally Posted by
onehundred80
I think they are normally open and should close when the temperature dial on the dash is turned to cold.
If the hose going to the firewall from the valve is hot then the valve is not working or the temp control for that valve on the dash is not working properly.
I'm told (in a GrayGhost post) that these valves cycle between open and closed faster or slower depending on the temperature setting, presumably totally shut in the cold position.
These valves cost about $45 used on eBay, which would put them over $500 at the dealers for new ones, just joking.
Hi Dave, GraphiteGhost, there is a greyghost member, just wanted to set the record straight. And, yes, they are normally open (NO) and close upon signal from the A/C head in the cabin. The design is to 'failsafe' to the heating position, hence the open state with no power.
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