Coolant heater addition. 1997 1078

[Blairg]

Was wondering if anybody has added one to their truck? Would like to heat water for the camper as well as have the motor in the loop as well. And if you have added a heater where did you tie into the motor cooling loop.

Thanks,
Blair

 

[TechnoWeenie]

While a hydronic heating system sounds great, it adds complexity.

With complexity, comes the increased opportunity for something to go wrong.

Why would you complicate one of the few systems that's REQUIRED for your engine to operate?

You get a coolant leak, and you're dead in the water. Sure, shutoff valves might work, but how long before you realize you've dumped all your coolant on the ground as you're driving down the highway? You got 10 gallons of coolant/distilled water on hand to top it off after you shut off the leaking lines?

Better off with a standalone heater, IMO.

 

[ramdough]

Was wondering if anybody has added one to their truck? Would like to heat water for the camper as well as have the motor in the loop as well. And if you have added a heater where did you tie into the motor cooling loop.

Thanks,
Blair

I plan to have a stand alone hydronic heater for the camper and maybe I will add the truck with a heat exchanger so the loops don’t mix. Still on the fence for the engine side.


Sent from my iPhone using Tapatalk

 

[Blairg]

While a hydronic heating system sounds great, it adds complexity.

With complexity, comes the increased opportunity for something to go wrong.

Why would you complicate one of the few systems that's REQUIRED for your engine to operate?

You get a coolant leak, and you're dead in the water. Sure, shutoff valves might work, but how long before you realize you've dumped all your coolant on the ground as you're driving down the highway? You got 10 gallons of coolant/distilled water on hand to top it off after you shut off the leaking lines?

Better off with a standalone heater, IMO.

My current design includes a marine water heater/tank and a diesel heater that will be used for the camper. I wll be able to use both 110v(shore power or inverted) or diesel depending what the siuation is. My thought was to add the ability to plumb into the motor cooling system if needed. I appreciate the addition of a failure point but pre-heaters are pretty common. I think the FMTV's came with a pre-heater in the acrtic packages.

Blair

 

[TechnoWeenie]

My current design includes a marine water heater/tank and a diesel heater that will be used for the camper. I wll be able to use both 110v(shore power or inverted) or diesel depending what the siuation is. My thought was to add the ability to plumb into the motor cooling system if needed. I appreciate the addition of a failure point but pre-heaters are pretty common. I think the FMTV's came with a pre-heater in the acrtic packages.

Blair

Some would say it's a minor risk.

They're probably not wrong. The odds of something going wrong are slim. The problem is, if they go wrong, can you implement a FER and get on the road?

You're on a forest service road and you get a leak.... how long until you realize you dumped all your coolant? When the overtemp light comes on?

How you gonna get down off the mountain?

Got a way to replace the coolant? I mean, I guess at that point anything liquid will do, but...

I just look at as certain things are mission critical.

Oil.
Fuel.
Coolant.

A truck will run with damn near nothing else working as long as you have those 3 things.

You lose one of those things, and you're dead in the water... So, just me personally, I wouldn't want Murphy to come visit me as I make things more complex.


My mission goals might be different than yours. If it's a grocery getter, stuck on pavement, and never more than 4 miles from a truck stop or Walmart.. then no big deal.

Going off road? Added complexity.


Same inverse reasoning is why I'm gonna have multiple sources of heat AND blankets/cold weather gear... No one has ever complained that their plan B or plan C saved their butt when plan A failed.

 

[Gibberogill]

I too am in the process of converting an M997A2 ambulance into a camper. I have purchased the Espar D5S diesel hydronic heater and have a similar plan to Blair. I read the comments made to Blair above and would like to address those first.

Added complexity: Yes, this definitely adds complexity to an already complex thermodynamic energy conversion plant (diesel engine). However, I am not creating a life-support piece of equipment. I am creating a hunting camper. I will not be in a primitive third world nation without resources to address unanticipated mechanical issues. I doubt I will face hostile forces intent on my destruction. I want to enjoy my time in nature and retire to a comfortable place at night so I can enjoy more time in nature.

Another way to look at this issue is by identifying the objective of the mission I will undertake. In this case, it is a hunting experience. What equipment do I need to fulfil that mission?? For me I want a warm place to shelter from the elements, a vehicle that will reliably start in very cold weather, and hot water. This diesel hydronic heater fulfills these needs remarkably well. This system will add 5-10 liters of additional coolant, there will be shut off valves to and from the engine if I want to isolate that loop from the camper portion of the loop if a leak were to occur. If anything, this system give me coolant volume redundancy with many additional benefits which further the intended purpose of this vehicle. In addition, I will not have to source and store an additional fuel source like propane.

So . . . given that I am willing to deal with the added complexity a hydronic coolant heater will add to this system, please accept that, for me, this type of conversion is consistent with the objectives I have in mind for an overland hunting camper. It may not be consistent with your mission parameters, but you are not the one paying for this conversion, nor are you the one who will be using this camper in a third-world combat situation.

 

[Gibberogill]

With that out of the way, I would like to know how those of you more experienced with the 6.5L platform (non-turbo) than I am would plumb the hydronic heater into the coolant system.

Here are my thoughts:

1. The line of heated coolant going from the hydronic heater to the engine I thought should be plumbed into the lower radiator hose to allow for the engine block and heater core to receive heated coolant prior to engine startup. Coolant in that hose is under the lowest pressure of anywhere I could plumb into in the coolant system. This makes the pressure differential of that location the most advantageous to pump heated coolant into from the Espar unit. On the other hand, I have read that coolant should be removed from the lowest part of the system to reduce the incidence of introducing bubbles into the hydronic coolant circuit. Any thoughts?

2. Where should I wye off to transfer pressurized coolant from the engine to the Espar unit? Ideally, I think it would be best to take the coolant from the back of the engine where the coolant is still under pressure. Taking coolant from this location would allow heated coolant from the Espar unit to transfer that heat to the engine block and heater core before going back to be reheated. It would also assist in pressurizing the line going to the Espar unit. Without removing a freeze plug and adapting a barbed fitting to the engine block, what would be the best way to accomplish this?

I appreciate any input that can help me solve this problem. Thank you.