heater bypass valve?

[The motor guy]

Anyone ever install one of these? My 99 dodge cummins takes coolant from the cylinder head, goes through the heater core and then returns it to the water pump according to a youtube video I watched. AFAIK it circulates coolant all the time whether you're using the heater or not, but my question is if you close this valve is the water pump still pumping coolant? Aren't you cutting off flow to the water pump? I would think that gives it a little bit of help cooling the engine in the summer, because it flowing through the heater core is like a mini radiator Opinions? I don't get how these valves make the ac colder, is it just cutting the hot heater core out of the system making it cooler inside the dash?

Amazon.com

 

[Dave Sherman]

Heaters often just have a split so some coolant is going through the heater and the radiator in parallel, so shutting off the heater entirely still allows coolant to go through the radiator. I believe my Pilot (maybe it was my old CR-V) actually has a valve that operates automatically to stop coolant going through the heater when the temperature is set to cold. My MG also has a heater valve, but you have to pop the hood and turn it by hand if you want to turn the heater on or off. Keeping the heater core cool probably would help the A/C since it's still inside the dash and not far from the evaporator.

 

[BMWTurboDzl]

Your engine must have more than just one coolant hose leading to the radiator.

On my vehicle the HCV is used to reach the set temp. The AC is cooling at max capacity and the cold air is reheated as it pass through the heater core. The amount of hot water running through the heater core to reach the desired temp. The HCV is electronically controlled.

 

[The motor guy]

Your engine must have more than just one coolant hose leading to the radiator.

On my vehicle the HCV is used to reach the set temp. The AC is cooling at max capacity and the cold air is reheated as it pass through the heater core. The amount of hot water running through the heater core to reach the desired temp. The HCV is electronically controlled.

The return heater hose goes to the water pump housing, not the radiator

 

[BMWTurboDzl]

The return heater hose goes to the water pump housing, not the radiator

The lines for the heater core branch off from that line correct?

 

[The motor guy]

The lines for the heater core branch off from that line correct?

The supply line goes from the cylinder head, then through the heater core and back to a return hose that goes into a hardline thats connected to the water pump housing is my understanding. So technically if I block that line, then I suppose I am reducing flow around cylinders 5 and 6 and cylinder 6 always runs a bit hotter then the rest because on the 5.9 cummins that's usually the cylinder that's damaged

 

[Chris142]

You need that heater hose. It's also the bypass when the thermostat is closed.

 

[BMWTurboDzl]

The supply line goes from the cylinder head, then through the heater core and back to a return hose that goes into a hardline thats connected to the water pump housing is my understanding. So technically if I block that line, then I suppose I am reducing flow around cylinders 5 and 6 and cylinder 6 always runs a bit hotter then the rest because on the 5.9 cummins that's usually the cylinder that's damaged

So there's a valve but it's not bypassing anything. Very strange.

 

[BrendanC]

i have one of these on my truck and the wife’s car. essentially a 2 way valve. one way it circulates back into the engine or the other selection it circulates through the heater core
Joywayus All Solid Brass Body Automobile Integrated 4-Way Heating Water Manual Control Valve 5/8” (16mm) OD Barb https://a.co/d/9rNVHZD

 

[The motor guy]

i have one of these on my truck and the wife’s car. essentially a 2 way valve. one way it circulates back into the engine or the other selection it circulates through the heater core
Joywayus All Solid Brass Body Automobile Integrated 4-Way Heating Water Manual Control Valve 5/8” (16mm) OD Barb https://a.co/d/9rNVHZD

That's true. Not sure who said it blocked off completely. Maybe I did and was confused lol

 

[MattPersman]

You are looking to solve a issue that doesn’t exist on a cummins

If you want to bypass the heater core do it with the 2 hoses together and take the heater core out of the equation

 

[bullwinkle]

I put something similar on the F-450 in my sig-coolant filter between the 2 heater hoses, & a brass ball valve between the filter & core on the “hot” heater hose. If I turn it off, then all the heater hose coolant passes through the filter & returns to the WP. Stops the non-air conditioned interior from getting as hot in summer. There has to be some bypass for when the thermostat is closed to allow coolant to circulate, or hot spots & possible boiling of coolant could occur.

 

[SHOZ]

I've got a NOS Ford vacuum operated one. Not sure what it was from but saw it and had to have it.....