Permanent Fix to summer heater control valve heat soak
#16
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I just test drove the car and it works flawlessly.
Left the valve closed and fully warmed up the car. Moved the heater lever to full hot and drive for a while with the valve still closed and got totally cool air out of all the vents. Pushed the button to open the valve and within 15 seconds I had hot air coming out of the vents. Moved the temp slider just.below half way and the air became cooler but was still warm. Moved it to full cool and it became cooler still. Presses the button to allow the valve to close again and it got cooler.once again with no warm coolant entering the heater core.
No leaks and no temperature gauge changes on the coolant temp gauge.
Calling this one done and a success and looking forward to no heat soak in the summer and not having to make any seasonal changes to the heater control valve.
Left the valve closed and fully warmed up the car. Moved the heater lever to full hot and drive for a while with the valve still closed and got totally cool air out of all the vents. Pushed the button to open the valve and within 15 seconds I had hot air coming out of the vents. Moved the temp slider just.below half way and the air became cooler but was still warm. Moved it to full cool and it became cooler still. Presses the button to allow the valve to close again and it got cooler.once again with no warm coolant entering the heater core.
No leaks and no temperature gauge changes on the coolant temp gauge.
Calling this one done and a success and looking forward to no heat soak in the summer and not having to make any seasonal changes to the heater control valve.
#17
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Quote from Petza914 . . "This is the solenoid I used from Amazon - 1/2" NPT Brass Electric Solenoid... https://www.amazon.com/dp/B01N0Q4QYI?ref=ppx_pop_mob_ap_share"
That is a nice install, but, here is a warning from the manufacturer of that particular valve:
"PLEASE NOTE: This valve is NOT a continuous duty valve and should NOT be in continuous use for more than 8 hours in a single cycle; to do so will shorten the life of the valve and may cause the core of the valve to burn out. If you need a continuous duty valve for your project please search for our U.S. SOLID Motorized Ball Valves"
.
That is a nice install, but, here is a warning from the manufacturer of that particular valve:
"PLEASE NOTE: This valve is NOT a continuous duty valve and should NOT be in continuous use for more than 8 hours in a single cycle; to do so will shorten the life of the valve and may cause the core of the valve to burn out. If you need a continuous duty valve for your project please search for our U.S. SOLID Motorized Ball Valves"
.
Last edited by GUMBALL; 03-27-2024 at 07:11 PM.
#18
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Quote from Petza914 . . "This is the solenoid I used from Amazon - 1/2" NPT Brass Electric Solenoid... https://www.amazon.com/dp/B01N0Q4QYI?ref=ppx_pop_mob_ap_share"
That is a nice install, but, here is a warning from the manufacturer of that particular valve:
PLEASE NOTE: This valve is NOT a continuous duty valve and should NOT be in continuous use for more than 8 hours in a single cycle; to do so will shorten the life of the valve and may cause the core of the valve to burn out. If you need a continuous duty valve for your project please search for our U.S. SOLID Motorized Ball Valves.
That is a nice install, but, here is a warning from the manufacturer of that particular valve:
PLEASE NOTE: This valve is NOT a continuous duty valve and should NOT be in continuous use for more than 8 hours in a single cycle; to do so will shorten the life of the valve and may cause the core of the valve to burn out. If you need a continuous duty valve for your project please search for our U.S. SOLID Motorized Ball Valves.
I have to stop for gas every 300 miles or so (every 3.5 hours) which will make it impossible for the valve to be in continuous use for anywhere near 8 hours. Most of my longer trips in the car are also during the summer too, which means it won't be energized at all on those as it's hot and I'll want it closed with is the non-enwrgized state.
#19
Three Wheelin'
I installed a 12v solenoid for >10 years ago and it worked brilliantly until I removed it to refine or fine-tune how much heat enters the cabin.
Problem with this valve is that it ONLY allows full or no flow to the cabin. My car lives in Florida and whenever heat is needed only a wee bit is required.
Post #6
https://rennlist.com/forums/928-foru...rol-valve.html
Instead, I have installed a solenoid that allows full control of how much hot water I want into the cabin.
Hope this helps others.
It is a product made by Vintage Air https://www.vintageair.com/ (no affiation)
Part #: 461178
The solenoid assembly fits against the firewall in the engine bay and the cables are long enough to get the controller in the cabin.
Problem with this valve is that it ONLY allows full or no flow to the cabin. My car lives in Florida and whenever heat is needed only a wee bit is required.
Post #6
https://rennlist.com/forums/928-foru...rol-valve.html
Instead, I have installed a solenoid that allows full control of how much hot water I want into the cabin.
Hope this helps others.
It is a product made by Vintage Air https://www.vintageair.com/ (no affiation)
Part #: 461178
The solenoid assembly fits against the firewall in the engine bay and the cables are long enough to get the controller in the cabin.
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9two8 (03-26-2024)
#20
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I installed a 12v solenoid for >10 years ago and it worked brilliantly until I removed it to refine or fine-tune how much heat enters the cabin.
Problem with this valve is that it ONLY allows full or no flow to the cabin. My car lives in Florida and whenever heat is needed only a wee bit is required.
Post #6
https://rennlist.com/forums/928-foru...rol-valve.html
Instead, I have installed a solenoid that allows full control of how much hot water I want into the cabin.
Hope this helps others.
It is a product made by Vintage Air https://www.vintageair.com/ (no affiation)
Part #: 461178
The solenoid assembly fits against the firewall in the engine bay and the cables are long enough to get the controller in the cabin.
Problem with this valve is that it ONLY allows full or no flow to the cabin. My car lives in Florida and whenever heat is needed only a wee bit is required.
Post #6
https://rennlist.com/forums/928-foru...rol-valve.html
Instead, I have installed a solenoid that allows full control of how much hot water I want into the cabin.
Hope this helps others.
It is a product made by Vintage Air https://www.vintageair.com/ (no affiation)
Part #: 461178
The solenoid assembly fits against the firewall in the engine bay and the cables are long enough to get the controller in the cabin.
You could certainly do it with variable flow as you have. What position does that valve go to when the power signal is removed from it - open or closed? The whole purpose of my project was to get a valve that was closed when the car was shut down to prevent the heat soak. If yours closed when no power then that's another good solution.
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davek9 (03-26-2024)
#21
Three Wheelin'
It is closed when you turn it fully closed.
Fully closed with no power
Anyways, for Fl's winter (not really winter) I found there was too much heat even with the slider controls.
Like I said in my text, I wanted to 'fine-tune' the heat supply and this does it for me.
Obviously, it differs for you
Fully closed with no power
Anyways, for Fl's winter (not really winter) I found there was too much heat even with the slider controls.
Like I said in my text, I wanted to 'fine-tune' the heat supply and this does it for me.
Obviously, it differs for you
#22
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Did a test with the heater valve today where I left it connected and engaged for 2 hours and measured the temperature using an infrared heat gun shot at the upper section of the of the solenoid every 15 minutes. it does get hot, but I don't think hot enough to be dangerous based on the clearance that's around it when installed because in cupping my hand over the top of it in close proximity to, but not touching it, it's just emanates some warmth.
As a refresher, here's the valve installed with the clearance around it. Based on the temp readings below, I think I'm going to replace this with a motorized ball valve as some of you have suggested to better control the heat emissions from the valve. Going to go with this stainless one -
The only things close to the solenoid are the metal lines above and below.
Starting temp before connection to the 12v power source
After 15 minutes
After 30 minutes
After 45 minutes
After 1 hour
After 1 hour and 15 minutes
After 1 hour and 30 minutes
After 1 hour and 45 minutes
Took another reading at 2 hours and it was the same as the above at just about 160 F, so it looks like that's where the temperature increase stops. This also is with no coolant moving through the valve, which when activated for cabin heat would allow coolant flow. I don't know if the valve would act as a heat sink for the solenoid and keep the temps when in use slightly lower or not.
After 2 hours, I disconnected the power supply and this is after 15 minutes of cool down
As a refresher, here's the valve installed with the clearance around it. Based on the temp readings below, I think I'm going to replace this with a motorized ball valve as some of you have suggested to better control the heat emissions from the valve. Going to go with this stainless one -
The only things close to the solenoid are the metal lines above and below.
Starting temp before connection to the 12v power source
After 15 minutes
After 30 minutes
After 45 minutes
After 1 hour
After 1 hour and 15 minutes
After 1 hour and 30 minutes
After 1 hour and 45 minutes
Took another reading at 2 hours and it was the same as the above at just about 160 F, so it looks like that's where the temperature increase stops. This also is with no coolant moving through the valve, which when activated for cabin heat would allow coolant flow. I don't know if the valve would act as a heat sink for the solenoid and keep the temps when in use slightly lower or not.
After 2 hours, I disconnected the power supply and this is after 15 minutes of cool down
Last edited by Petza914; 04-05-2024 at 12:53 AM.
#23
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Replaced the electric solenoid valve with the electric ball valve tonight.
This is a better solution as it only opens when energized, then cuts power to the motor, but monitors the signal to stay open as long as it's receiving power, which means it will close automatically when the ignition is shut off or when I push the dash button.
This is the new ball valve and is a 2-wire with what they called "Auto-return" which means it closes automatically when power is removed
Installed in same spot but the top assembly is a little larger
I used some high density foam tape to isolate it from the metal lines it's close to on the left and underside
Wired up with disconnects this time in case I need to swap it at a later date or remove it to work on something.
Still tucks in under the airbox without touching.
This is a better solution as it only opens when energized, then cuts power to the motor, but monitors the signal to stay open as long as it's receiving power, which means it will close automatically when the ignition is shut off or when I push the dash button.
This is the new ball valve and is a 2-wire with what they called "Auto-return" which means it closes automatically when power is removed
Installed in same spot but the top assembly is a little larger
I used some high density foam tape to isolate it from the metal lines it's close to on the left and underside
Wired up with disconnects this time in case I need to swap it at a later date or remove it to work on something.
Still tucks in under the airbox without touching.
Last edited by Petza914; 07-23-2024 at 12:06 PM.
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WestInc (04-08-2024)
#24
I probably missed the geographic location of the OP.
Hot cars take on a unique representation in the southeast US (100 degrees, 90% humidity with no falling precipitation). But the deserts are seriously unique representers of “heat” once the sun is above the horizon.
In the mid-Atlantic, with leak free AC seals, heater valve subject to full vacuum, HVAC temp set to 65 and outside temp at just above 90 degrees, within 15 mins it gets too cold not to add a little heat to the air flow. This even with the car having set outside in the sun before entry.
But in the southeast, it wasn’t uncommon on one of those days to be required by passengers to FIRST start the car, turn AC on and let it run for a bit before anyone would take a seat in the sauna. I can only imagine how it is in the desert. I’d be afraid to run AC in my 928 on a heat defining day in the desert.
Hot cars take on a unique representation in the southeast US (100 degrees, 90% humidity with no falling precipitation). But the deserts are seriously unique representers of “heat” once the sun is above the horizon.
In the mid-Atlantic, with leak free AC seals, heater valve subject to full vacuum, HVAC temp set to 65 and outside temp at just above 90 degrees, within 15 mins it gets too cold not to add a little heat to the air flow. This even with the car having set outside in the sun before entry.
But in the southeast, it wasn’t uncommon on one of those days to be required by passengers to FIRST start the car, turn AC on and let it run for a bit before anyone would take a seat in the sauna. I can only imagine how it is in the desert. I’d be afraid to run AC in my 928 on a heat defining day in the desert.
#25
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I love the idea of the electrical solenoid. A more complex thought is to add an activation line into the HVAC controller, so when the slider is moved into the “heat” zone, power is activated to the circuit. This will reduce “training” and make it part of the system? All is needed is minor mods.
#26
Rennlist Member
I love the idea of the electrical solenoid. A more complex thought is to add an activation line into the HVAC controller, so when the slider is moved into the “heat” zone, power is activated to the circuit. This will reduce “training” and make it part of the system? All is needed is minor mods.
I am changing to an electric ball valve as described above, however. I didn't know we had those, but I am sticking with the factory configuration and purchased a normally open one (as vacuum closed the orig. one, current closes the ball valve).
With engine off, ball valve opens and allows coolant to circulate in the heater element. I adjusted the climate control "doors" to account for the disintegration of the factory foam.
I never had any trouble from the original electric solenoid based valve I put in when I built it but love the idea of the mechanism not being constantly powered up while running but instead closing the valve and "monitoring" the power lead and automatically opening the valve back when the power turns off....
I like being able to have it work the way it was designed. Having access to electric valve equipment is what was missing...all the other elements are present in the car...there are extra fuse spots and empty relay slots so its all right there available to do...
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khalloudy (04-10-2024)
#29
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@Petza914 I had a quick question. By installing this valve, how would you limit the amount heated coolant that enters the heater cooler any better than factory vacuum pump. Does the OEM version allow a portion through, thus affecting cabin heat?
I've now had both hot days (94 yesterday) and cooler days where I needed heat, and the setup works perfectly. The heat slider blends in cooler air with warm air when you don't want it full hot. Another benefit I didn't think of is that when you need the defroster in the rain on a summer day, you don't have to have it on full hot and it can be on cold by leaving the valve closed, or you can occasionally open and close the valve with defrost on to regulate the heat, which you can't do with the OEM setup where the heat is on full blast with full fan speed when defrost is selected.
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Snowglobe (06-27-2024)
#30
No, the factory valve is fully open with no vacuum issue to the spring and fully closed with vacuum. Itsbdiesnt partially open.
I've now had both hot days (94 yesterday) and cooler days where I needed heat, and the setup works perfectly. The heat slider blends in cooler air with warm air when you don't want it full hot. Another benefit I didn't think of is that when you need the defroster in the rain on a summer day, you don't have to have it on full hot and it can be on cold by leaving the valve closed, or you can occasionally open and close the valve with defrost on to regulate the heat, which you can't do with the OEM setup where the heat is on full blast with full fan speed when defrost is selected.
I've now had both hot days (94 yesterday) and cooler days where I needed heat, and the setup works perfectly. The heat slider blends in cooler air with warm air when you don't want it full hot. Another benefit I didn't think of is that when you need the defroster in the rain on a summer day, you don't have to have it on full hot and it can be on cold by leaving the valve closed, or you can occasionally open and close the valve with defrost on to regulate the heat, which you can't do with the OEM setup where the heat is on full blast with full fan speed when defrost is selected.