block heater question

[team bradfield]

I'm plugged into shore power, I assume all I need to do is flip the switch in the OH cabinet to turn it on, should I leave it on all the time?

 

[stang37]

I've used my block heater a few times. Once while in South Dakota when it was below 30 degrees and was staying that cold for a week. I turned it on for about 2 days before leaving to make sure the oil was warm and wouldn't take so long for the engine to get to operating temperature. I'm not a fan of starting an engine with oil temperature around 30 degrees even though it synthetic oil.

 

[team bradfield]

so, my question was, do I leave it on all the time

 

[Rich W.]

Just looked at some 2023 DS control panel pics and saw the block heater switch. I would only turn it on when needed.

 

[NWIP]

Not only is there a switch in the overhead but also a plug in the engine compartment. I don’t leave mine plugged in and sometimes use the 110v outlet for other things, ie vacuum for cleaning out the truck.

At Spartan academy recommendation was below 40* to use and turn it on 12-24 hrs prior to engine start.

 

[stang37]

The answer for me in no. Why add heat to the oil when it's above 60 degrees outside? Will it hurt the oil no. But if I was staying somewhere and the temperature was going to be below 40 degrees I would have it on for as long as needed. I left mine on while traveling to a warmer area. I wouldn't turn it off until I relocated in an area where the temperature was going to stay above 40 degrees. Per my discussion with Freightliner 24/7 it will never get too hot

 

[Neemer]

No need for it beyond startup.

 

[GlampDaddy]

I'm plugged into shore power, I assume all I need to do is flip the switch in the OH cabinet to turn it on, should I leave it on all the time?

In addition to the switch and the plug in the engine compartment, you also have a breaker that has to be turned on. Our Newmar tech told me to leave it turned on any time the temps were at 40 or below.

 

[team bradfield]

In addition to the switch and the plug in the engine compartment, you also have a breaker that has to be turned on. Our Newmar tech told me to leave it turned on any time the temps were at 40 or below.

That seems kinda redundant, plugged into shore power and plugging in the engine block? Salesman (I know, salesman) said I didn't need to do anything but hit the switch on shore power, boondocking use the genny, he didn't show me a engine plug in, I will have to look for it when it gets a little warmer, not going anywhere soon, its below 20f today and windy, brrrr. Should be 40's by Wednesday

 

[Rich W.]

Ok I’ll chime back in here. The switch in the overhead is relatively new adddition to the system (around 2020?). In older coaches we just have a breaker and the plug so we leave it unplugged because turning off the breaker causes other problems with line 2 (precision circuits display) related to how things are wired in the breaker box (don’t recall the exact reason, but the pic shows what happens).

So sometime around 2020 they added the switch (second pic) allowing you to leave it plugged in, breaker on, and still have the block heater off, and then turn it on easily as necessary. This makes sense, is an improvement, answers the OP’s question, and agrees with all of the above: turn it on when needed, off the rest of the time. And those with newer coaches can do this with the switch, rather than unplugging it since the breakers should be left on.

Until I discovered the ”new” switch, I also though the OP might have had the optional Oasis Engine Pre-heat since he describes the switch as residing in the overhead cab (third pic just for fun). Anyway this discussion has come full circle this morning and since I plugged mine in last nignt and recorded the temp, I’ll go out and check it now to see what it has accomplished.

 

[Rich W.]

That seems kinda redundant, plugged into shore power and plugging in the engine block? Salesman (I know, salesman) said I didn't need to do anything but hit the switch on shore power, boondocking use the genny, he didn't show me a engine plug in, I will have to look for it when it gets a little warmer, not going anywhere soon, its below 20f today and windy, brrrr. Should be 40's by Wednesday

You fall into the ”new system” categoty. You would just always leave yours plugged in, use the switch, on or off as needed, and not worry about the rest. The plug (and outlet) are near the engine, either in the compartment just forward of the radiator or in the passenger side rear compartment. There is not an external cord that you plug in somewhere. Or maybe the newer rigs don't even have the plug, since its been made redundant as you observed, and I’d say your had it right.

I only checked 2020 - 2023 so I don’t know exactly when they added the switch in the overhead. Since this falls into the “wheelhouse” of my nerdy need-to-know-about-these-things hobby, I’ll probably keep digging a bit so I know when this change was made, though admittedly it doesnt matter at all.

 

[Rich W.]

So a little update. Since I’m in California at 1150’ elevation, and usually steer clear of traveling in colder climes, I don’t normally use the block heater. But I plugged it in last night to test it and the “cold” engine temp was 57°. This morning it‘s at 104°. Apparently it works and I’m certain my little 6.7 (as with any diesel) would rather be started warm than cold. So I‘ll use it more often, but as detailed above, for me and those with earlier coaches, this means unplugging it and plugging it back in, since the breaker has to be left on. That’s something to do with the inverter also supplying line 2, but I’m still a little foggy on that.

@GlampDaddy, I changed my outlet to a conventional type so I can also use that circuit for other things as you mentioned, and because I don’t like the cheap RV outlets. For me its usually used for a charger for my cordless tools. See pic - that compartment is a bit messy since Im working on some stuff, but it gives you the idea. I also made that change before I installed that shelf and moved the light, but it was still a cramped, busy space to work in. Since you have a side radiator, I’m guessing your block heater plug and outlet are in the rear most driver’s side compartment? Or are they in the “service bay” on the other side?

 

[Joe Hogan]

Here is the setup in the 2024 DS

 

[Neal]

Love the display and the newer OASIS setup. However, what is in the bubble wrap to the right of the OASIS? And it's right on your door latch so be careful!!

 

[Neal]

There are various options for block heaters as I understand it. One is an electrical setup that some turn on inside the coach, some of us have a plug in the aft of the coach such as mine is in the left aft compartment. It is a high amp draw and requires shore power (not inverter).

The other option is to add an additional pump into the OASIS system, if you have one, that circulates the heater fluid which has a path to/from the engine that can warm it. Many of us have a "blank" in our control panel in the control for this switch which can be swapped out if you add the pump per ITR at the recent Newmar Hoots rally. Some have it built into KIB or Silverleaf from what I understand. Maybe the new Chinook OASIS models in newer Newmar coaches have this pump in by default? A call/question to ITR would be good to get an answer to share here for those with Chinooks and recent coaches, cough, Joe!

As to when to use it. This is another one of those 8 gagillion opinions like tire pressure so I'll add mine. I'm in freezing temps as I type this. What I am monitoring is how long the "glow" light is on before it goes out so that the engine is ready to start. In colder climates this will be longer. On some coaches I think on digital dashes this is a wait to start indicator. In the climate I'm in now (around 30F in the morning), it's all of maybe 3 seconds.

So in my opinion, the block heater is for people camping in the northern US, CA, and Alaska, i.e. temps below 20 or near or below 0 F. I do not agree with the 40F suggestion, it is not necessary IMHO. I think for most of us it is not necessary and adds no benefit other than significantly higher electrical loads and wasted electricity.

 

[Kevin D Pem]

Yah! You all have heard that thing about!
I had to replace my _______ because I used it to much when it was new!

Don't over think this! Outlets have heat treated terminals so they will hold their shape. Used to much they do wear. Heating elements have a life or useful life.

I find the idea a standard item (block heater) would be replaced by a long corded item, or that it would be hard wired. Anyone servicing such an ill installed device would have a lot to say about the factory that did the job!!!

 

[Neal]

Let's try to debunk opinions and see if we can figure out the right answer(s). My google search - click here

20F according to this article

Per this article:

Newer models of vehicles can start at temperatures as low as -22°F. One official rule of thumb is to plug in your block heater if the temperature drops to 5°F. But to be safer and to ensure a better running engine, it is better to plug it in when the temperatures are below 15 degrees.

As for the length of time to use an engine block heater, anywhere between two to four hours is the recommended time. Again, this would also depend on how low the temperature is. Plugging it in for more than four hours is just going to be a waste of electricity, but it will not harm your vehicle. You could use an electrical plug timer that will activate the block heater plug at certain times. This saves you time and money.

 

[Rd1]

Neal; "So in my opinion, the block heater is for people camping in the northern US, CA, and Alaska, i.e. temps below 20 or near or below 0 F. I do not agree with the 40F suggestion, it is not necessary IMHO. I think for most of us it is not necessary and adds no benefit other than significantly higher electrical loads and wasted electricity"

Spot on.

One, if you have been driving for some hours and then park over nite, even if below 30, there is no need for a block heater. the engine core temp remains warm enough for the next am startup. just give it a few mins for the engine/trans temps to stablize and a slow start off camp area to hwy speed, is just fine.

I've driven in 18F wyoming snow bleezards and parked in rest area overnite for 5-6 hrs, without block heater. next day a 5 min warmup while I get ready and a slow moving (40-45mph) for 10-15min for everything to warmup before hitting cruise speed.

If you are parked long term and temps are 30 or even below, 3-4 hrs is enough to get heat for startup. if 20s or lower, then overnite 7-8hrs of block heater.