Heater and the associated Actuator
 

So many of us have that ugly contraption on the fire wall for the heater core.

See the pic in this thread: https://www.clublexus.com/forums/4920428-post5.html

Is that thing required to be there or can we bypass it entirely? When I went single I took the whole unit out and bypassed the heater core entirely being in Florida. Well the last two weeks has made me rethink that as I haven't really wanted to drive the car an hour to work in the low 40s with no heat :sad: Plus, it's nice to have it working in an emergency overheating situation.

My question: Does that actuator control the actual heat flowing through the a/c vents or is that handled by some sort of electronic actuator under the dash to divert air through the heater core? I do NOT want to reinstall the actuator, but I can easily reconnect the heater core....

yes the actuator is controled by the climate control and vacuume. climate control send signal to actuator allowing a vacume to open up and let collant in thus creating hot air also at the same time the heater vent opens up. Well atleats thats how it was explained to me when my tech simply changed over a vaccume line and like magic I had heat that i never did LoL

Yes it does control it, but remember what the actuator is. It just takes vacuum and converts it into mechanical motion.






In short, it physically moves something. Look to where the actuator arm should be and you will find a sort of "lever". One position is closed, the other is open.

You just need to find a way to pull it in the direction you want and viola, flow to your heater core.

Also, look into how mkiv supras control coolant flow into the heater core. I think they do not have a climate control unit so they don't have the vsv or actuator. Maybe you can adapt it somehow? I don't know, just throwing out ideas.

Hope that helps.

*Edit* I think the heater vents are only controlled by the actual switch, not the vsv actuator.

I understand how it works and that its basically the gate keeper for coolant flow into the heater core. My question remains, if I bypass it and hot coolant continually flows through the heater core (like it does on many other makes/models of cars) will that force the heat to be ON all the time?

According to your link it does not negate A/C, so no it will not be like having the heat on 24/7. I have no first hand experience, so I would say just try it. Its not that hard to do, and you can always switch it back down.

jordon if you want try on a car that still has it.keep it open.then crank on the A/C and see if you get cold air.

Hrm....didn't think about that...good idea richard!

I basically said the same thing... :(

Sad panda face

lol ..... :thumbup:

ha indeed you did :egads: That'll teach me to read more gooder.

Yes I bypassed this in my LS400 it works fine without it.

Ok ,there is a flap that covers the heater core when you turn the knob to cold, while in same time it shuts off the coolant gate(heater VSV).

So if you have the VSV open all the time ,the flap will still close the heater core to keep the hot air going through it.......

BUT...

Your heater will always stay hot because the heater core will be hot. So if you turn off the heater you will still feel the heat from the whole assembly, untill you turn the AC on.