Heater valve bypass to fix "heated dashboard vents"?

[Gooseberry]

http://www.google.com/imgres?imgrefu...dM&h=612&w=800


would this work only $90

[JWA]

Originally Posted by Gooseberry

http://www.google.com/imgres?imgrefu...dM&h=612&w=800


would this work only $90

Yeah it would work but its a bit of overkill for this use. If all we need is to stop coolant flow there'd be no need to modulate that flow like it seems that valve and control would do.

That is an excellent replacement for the older cable-driven temperature controls but maybe just a tad more than needed for this project?

[carringb]

Originally Posted by JWA

That's interesting CarringB you had those failures----I check my hose connections :

It's also likely I'm getting a lot higher coolant temps there than typical. Moving 25,000 pounds up a 6% grade at 60 mph makes a lot of heat. And yeah, very possible I over tightened it as well. I have not had the same problem at other locations, only at the manifold outlet.

[JWA]

CarringB there was a time early on in my career of DIY auto repairs I too would tighten hose clamps until the hose itself was oozing out from those little "threads" in the band---not my brightest moments. Your idea of the spring clamp on a barbed fitting is one of the best alternatives as those do hold up to temps and pressures normally found in coolant circulation connections.

Over time I've discovered several very loose band clamps, almost to the point they weren't really doing much, not of my own installation mind you. For whatever reason the connection was still pressure tight, no signs of leaks anywhere. While I still recommend a snug tightening this does show the pressures seen in typical automotive cooling systems is relatively low.

Higher temps as you experience are another issue, not sure if a silicone hose would solve that for you?

[carringb]

Originally Posted by JWA

Higher temps as you experience are another issue, not sure if a silicone hose would solve that for you?

it would, and I have some. But the clean routing of the factory 3-way heater hose (for dual HVAC) can't be beat. And it hasn't been an issue since I went back to the spring clamp. The original one lasted 350,000 miles anyways so if I get half that on he current hose, I'll be happy. By then it might be time to start thinking about something a little newer.

[Scalf77]

OK. I did some testing this evening, I was able to hook up the http://www.dieselsite.com/maxacassis...200373l-1.aspx and test that it closed with The max A/C, A/C, and Vent setting. It would work on all the other settings OFF, Floor,Mix and Defrost. I expect that I will need to get a different T then the one that came with the kit to fit the Line I am attaching it to. To test I just hooked into port 4 vacuum line (this was conveniently located under the panel on the dash-mid passenger side). Tonight all I did was hook into this vacuum line and test the max AC control valve in all the settings. I will do a proper write up on the install when I get around to actually doing it in a couple off weeks





I applaud JWA in his DIY attitude, I have some reservations on the electrical valve holding up in the Engine Compartment. This also allows me not have to add any switches or power to get the job done, and I won't have to remember to turn it on off depending on the setting I am in.

-greg

[JWA]

Sounds great Scalf77 aka Greg! I'll look forward to the installation process as well as your final impressions.

There's merit in both approaches, depending which one seems better or best for any individual user will probably dictate the kit version or my ideas.

Hope the install goes as easy as the testing!

[Scalf77]

Originally Posted by JWA

Sounds great Scalf77 aka Greg! I'll look forward to the installation process as well as your final impressions.

There's merit in both approaches, depending which one seems better or best for any individual user will probably dictate the kit version or my ideas.

I agree, I wouldn't hold my breath for the full install ( I've had the kit for over a year) and I am in the time of year where it won't be important for me.

This has been a great thread, as it renewed my interest in installing the kit, which actually made me look at the instructions, it was there that I noticed that there was a vacuum setting that would work in the vans that PU trucks did not have. That actually makes this a pretty easy installation "no cold rush needed", and really how it should have been designed from the beginning, but then again I am not a car designer.

-greg

[JWA]

Ya know Greg I'm loath to understand why the original heater control valve was replaced by the blend doors---even in theory it makes little sense. Hot coolant flowing through the heater core full time means temps above ambient will always be present, the blend door useless for a true cool air flow.

Without bashing the MaxAir and ColdRush kits my only real concern was how they seemed to work only in concert with one another. This increases the cost without necessity, IHMO anyway. I've already DIY sourced and installed something similar for far less money however my experience and lack of concern of not having a mobile vehicle during my experiments figures greatly into all that.

On another point about the electric-actuated valves I suggested---they would be slightly better than the composite cast vacuum valves the MaxAir and ColdRush kits feature. That's NOT saying those parts are one bit inferior as they appear to be the brand Four Seasons which is a huge supplier of all sorts of automotive specific coolant flow devices--I have a few in operation right now.

My point is underhood temps aren't excessive which allows the use of the composite materials with high confidence. OTOH my valve choice is a brass body rated for much higher temps and pressures than we'll ever see during normal operation. The ONLY benefit to the electric actuation is it doesn't require digging into the vacuum control system which some might find ever so slightly "intimidating".

Greg whenever you get around to installing your kit it will be great seeing it in action---as we head into winter or whatever passes for it locally "cool air flow" isn't our top priority.

[Scalf77]

JWA I hear ya. I do like your solution, and probably would lean that way, but I already have the Max Air. My concerns around the valve in engine compartment are not on the valve or valve body, but the electrical turning it on or off. It has a 1.8 amp current draw to stay closed. Part of my work experience is to break things with hot and cold temperatures. Admittedly I did not really dig any deeper into it, but other things I would look at would be the possible failure modes. In failure does it get stuck in the closed position or in the normally open position. I suspect most likely open, but if it were closed then I might design differently.

The Max Air solution was a simple automotive fix for a automotive problem. In reality it did exactly what it was intended to do, turn off water to the heater when the Max A/C setting was used. It did it using standard parts used in automotive applications, so I don't really fault them for that. I do see it as a solution for a non-problem, I never had an issue with my AC temperature.

I think the Cold Rush was a afterthought, and they probably would have done better, just putting the two together in one package. Again, they used a simple automotive solution, for the problem at hand and provided an upgrade path for the existing MAX AC units they had sold. Choosing a vacuum controlled valves is really what I would have expected, they are car guys.

So I think there solution is fine, there documentation and sales propaganda need work. Your solution is definitely thinking outside the automotive box, it is more cost efficient, then purchasing the two Dieselsite products together. I suspect the cost difference gets a little tighter when comparing just the Max AC by itself (in a Van), once you add the switch, fuse, wire, etc. But, then again it would not be as full featured (having complete control) as your solution and the combined Dieselsite solution.

We have provided options, for a common complaint in our vehicles, which is a what the forum is all about.

greg