Heater Control Valve or Shut Off Valve
#1
Heater Control Valve or Shut Off Valve
I want to put a shut off valve on my heater core for the summer. I don't mind having a manual shut off valve, however it would be pretty easy to install a heater control valve. My experience is a heater control valve is another extra level of complexity and I prefer to keep things as simple as possible.
What are the compelling reasons to install a heater control valve over a manual shut off valve?
Thanks,
Brandon
What are the compelling reasons to install a heater control valve over a manual shut off valve?
Thanks,
Brandon
#5
TECH Veteran
iTrader: (4)
Newer cars use blend doors to keep hot air out when not needed, but coolant always circulates through the heater core. That's why there is a lot of drama as to whether or not you should block off the heater hoses on an LS engine. I have used heater control valves that shut the water off completely on swaps for years with no I'll effects.
#7
TECH Junkie
iTrader: (1)
I use a Classic Auto Air system with fully electronic heater control valve that shuts completely off when you tell it to. And I simply used two 5/8” x 5/8” x 1/8” tees between the heater hoses - that allows a small amount of coolant to always be flowing across the back side of the t’stat as GM desired.
Trending Topics
#9
TECH Junkie
iTrader: (1)
If you're using the original dash controls, they were almost certainly vacuum operated. The LS engines were designed to bypass the heater core with a 4 port HCV, although I've used conventional shutoffs on both my swaps with no effects. Andrews would work well for vacuum operated.
In addition IIRC the Lincoln LS used an electronic 4 port HCV if you want to go that route.
Classic auto air also has a 2 port cable operated HCV if you need that.
In addition IIRC the Lincoln LS used an electronic 4 port HCV if you want to go that route.
Classic auto air also has a 2 port cable operated HCV if you need that.
#10
TECH Junkie
iTrader: (1)
Then there's this -- nice piece -- https://www.lojkits.com/products/ls-...r-bypass-block. Then put your heater control valve between the bypass and the core.
#11
Michael, what would be the difference between using Andrews and using the unit you mentioned and then adding a valve between the core and the Nissan unit? Are you saying that the unit Andrew posted allows some to bypass into the heater core even when shut off and that adding the Nissan unit would allow no flow at all?
#13
TECH Junkie
iTrader: (1)
I wasn’t “saying” anything at all about the unit Andrew showed - I don’t have a clue how it works or what it does. I was simply showing a way you could 1) assure you have some constant flow around the t’stat as GM designed it to work, and 2) be able to control coolant to the heater core.
#14
TECH Senior Member
iTrader: (7)
For the record, I don't know anything about that valve. I remember finding it in some searches I was doing and book marking it. I believe it is from a late model GTO, but I could be way off on that.
Andrew
Andrew
#15
TECH Addict
70's fords had a pure shutoff valve, same with old mopar,, gm went full flow much earlier than some, found out it helped prevent air lock in the cooling system. YMMV