When I flip the engine heat button the AH makes a funny noise. Almost like a fan not being able to turn. I left it on for a minute but I switched it off.
Is that sound normal.
First time I did it.
Also what is the 115vac switch for?
Rick,
1. Sounds like you may have a zone circulating pump failing that is for the engine heat loop.
2. When that switch is on it powers an 120VAC heating element it the A/H unit. This can be used with the diesel side or independent. If only on 120 you will have limited heat.
Mike
If you haven't been using the engine heat switch, I'd go ahead and flip it on. It only controls a valve that allows engine coolant to circulate through the A-H. You need to have either the diesel or electric switch on to actually heat the coolant. You can feel the engine head or use an IR gun to confirm the valve did open.
The valve Brett referred to is actually the Engine Preheat Pump. Once turned on it circulates engine coolant from the engine, thru the heater and back to the engine.
This switch is only on for the hour or two to maybe overnight when starting the engine in very cold conditions.
With the preheat switch off and main engine running, the main engine water pump circulates hot engine coolant through this loop heating the Aqua Hot coolant.
Hope this helps
At what temperature should you use this. It's 31;degrees here.
It certainly wouldn't hurt to turn it on at that temperature, but you don't necessarily have to. I've started our Cummins at temperatures in the mid-20s without preheating without any problem.
I use mine any time it's below 40 deg. Sure doesn't hurt to have a warm eng when starting!
So I did preheat the engine and it did start better than the last few times when I started it in similar cold temps (it always started
right away but after a few seconds after firing up it seemed like it was going to stall; and that lasted only a couple of seconds).
Thanks for the help
Rick, starting any engine warm is better than cold starts-- Yes they will start cold but until the oil is warm it don't flow through the filter as easily. I heat my engine year around--always warm start, Just me!
Chris
I was told one time to be sure and turn the preheat switch off before starting the engine. Did not ask why.
Lynn, I assumed( you know what that gets you) that the water pump may be pushing water in the opposite direction as the aqua hot
pump, but have not been able to verify that.-- BTY I was told the same thing plus turn off block heater!
Yes, make sure to turn off the block heater before starting the engine. It will burn out and be expensive to replace. Don't ask how I know.