I can figure this out, but a heads up would be nice. What's going on is the heat doesn't shut all the way off. when summer gets here the AC will be in competition with the heater. Is it hard to get to the heater cable to adjust?

I had to splice 2 shut off valves into the water lines going into the heater core to prevent this problem. 

I've gone to the two cut off valves on mine as well.

If you only use one valve, you still have hot water backing up to the heater core, so 2 valves will keep it cooler.

The vacuum operating valve will only do so much, as it is only in one side of the line so you have the same issue as above.  The valves are cheap.

You need to check to see if you have the correct 3/4 and 5/8 lines or if someone did like mine and put 3/4 on both sides.  I changed out the lines first, then installed the valves in the new lines.  You can also get the valves at Auto Zone and other parts houses, just tell them the size you need for the hoses.

Thanks!!! I'll check it out this weekend. Since it's going to be 50 to 60 degrees. I don't have a garage so I have it  covered and a tarp to protect it. Not very good to do winterTime work. But Good News.... Spring IS Coming !

Somewhere in here I posted a NAPA part number for the valve if I remember correctly...

  Found it.....NAPA Part number is 660-1414 JimG2007-03-01 05:49:14

Thanks!!!

I when to napaonline ,.. But that # didn't showup. but when I looked for heater valve 660-1200 did  . That one?

You won't get it on line..go to the store and give them the number...I don't know why.

BTW, here is the old thread where we talked about this before. Might give you some ideas.