Itasca 2003 rear heater?

[murraymcleod]

I have a 2003 Itasca 27 class A that has a rear heater under the bed. I'm trying to figure out how this thing works (it does work when driving). It has electrical wires running in to it and seems to have water lines (from the hot water heater?) going in as well. Does the hot water heater provide the warmth or what? Thanks.

[TNGW1500SE]

murraymcleod wrote:
We took a trip this week and I verified the water was not hot after more than an hour of driving. My Atwood model is GH6-8E which according to the interwebs does support motor heating. So what coolant temperature is spec for the Chevy Vortec 8.1 engine? Maybe I do need a new thermostat, but what is the problem with a cool running engine? Can this affect gas mileage? Thanks.

You could have a bad gauge. Is there really warm air coming out the dash vents when on max heat after the engine has "warmed up"?

If your engine is running to cold, then I'd replace the thermostat. The thermostat holds the water in the engine until it reaches operating temperature. Once it does it opens to allow water to flow from the radiator thereby controlling engine temperature. Sounds like your thermostat is stuck open and letting cooler water flow from the radiator all the time. Should be a easy fix.

Watch this: How a Thermostat works

[dougrainer]

murraymcleod wrote:
We took a trip this week and I verified the water was not hot after more than an hour of driving. My Atwood model is GH6-8E which according to the interwebs does support motor heating. So what coolant temperature is spec for the Chevy Vortec 8.1 engine? Maybe I do need a new thermostat, but what is the problem with a cool running engine? Can this affect gas mileage? Thanks.

An Engine NOT running to spec Heat will affect all parameters of the engine, including gas mileage. Doug

Also, driving just 1 hour probably will not heat up the Tank water. ALL the MotorAid system is, it is an aluminum tube about 12 inches long welded to the OUTSIDE of the Tank, NOT thru the tank. So, you have about 6 inches of 3/4 inch aluminum tube welded on the outside of the tank and that will radiate the heat to the Tank itself. It probably takes at least 3 or more hours of driving and also if the engine is not running at the normal 180 degrees plus but is lower will affect how much heat is transferred.

[murraymcleod]

We took a trip this week and I verified the water was not hot after more than an hour of driving. My Atwood model is GH6-8E which according to the interwebs does support motor heating. So what coolant temperature is spec for the Chevy Vortec 8.1 engine? Maybe I do need a new thermostat, but what is the problem with a cool running engine? Can this affect gas mileage? Thanks.

[mfinnerty]

There are aluminum tubes for the water lines from the near the front wheel to near the rear wheel and up over the frame rail on the drivers side. At both ends there is heater hose connected as part of the system. On my 2003 the rear bend of the aluminum tubes became corroded and started leaking antifreeze. Had to remove the tubes and replace then with heater hose. Fortunately it failed in my driveway.

[TNGW1500SE]

dougrainer wrote:

murraymcleod wrote:

dougrainer wrote:
The Hot water runs thru the Water Heater loop all the time. You do NOT have to turn the Water Heater ON. You CANNOT even turn this heat function OFF to the Water Heater. Doug

That probably explains why my RV runs pretty cool most of the time(not much over 150 degrees according to the gauge)!

(BTW....anyone know why the "subscribe and send email notifications..." doesn't seem to work for me?! The signature only seems to work intermittently as well, or does it only show once per thread?)

If your engine is NOT running to temp spec, it will NOT be the rear heater and Water Heater Motoraid system causing that. Doug

Probably a bad thermostat.

[dougrainer]

murraymcleod wrote:

dougrainer wrote:
The Hot water runs thru the Water Heater loop all the time. You do NOT have to turn the Water Heater ON. You CANNOT even turn this heat function OFF to the Water Heater. Doug

That probably explains why my RV runs pretty cool most of the time(not much over 150 degrees according to the gauge)!

(BTW....anyone know why the "subscribe and send email notifications..." doesn't seem to work for me?! The signature only seems to work intermittently as well, or does it only show once per thread?)

If your engine is NOT running to temp spec, it will NOT be the rear heater and Water Heater Motoraid system causing that. Doug

[murraymcleod]

dougrainer wrote:
The Hot water runs thru the Water Heater loop all the time. You do NOT have to turn the Water Heater ON. You CANNOT even turn this heat function OFF to the Water Heater. Doug

That probably explains why my RV runs pretty cool most of the time(not much over 150 degrees according to the gauge)!

(BTW....anyone know why the "subscribe and send email notifications..." doesn't seem to work for me?! The signature only seems to work intermittently as well, or does it only show once per thread?)

[dougrainer]

murraymcleod wrote:
You say it works like the dash heater, meaning hot radiator water flows through a heat exchanger at the rear of the coach? And it will also heat up water in the hot water tank, when turned on?

The Hot water runs thru the Water Heater loop all the time. You do NOT have to turn the Water Heater ON. You CANNOT even turn this heat function OFF to the Water Heater. Doug

[TNGW1500SE]

My 30B has a blower switch on the dash that operates the rear heater. It has a High and a Low.

[AstroRig57]

murraymcleod wrote:
You say it works like the dash heater, meaning hot radiator water flows through a heat exchanger at the rear of the coach? And it will also heat up water in the hot water tank, when turned on?

Yes. You have second heater core under your bed. Be sure to check the lines, which run all the way back from the engine, and maintain them on a regular basis. You also have "Motor Aid" hot water heating which routes engine cooling water to a heat exchanger around your water heater.

See Sections 2-11 and 8-8.

2003 Itasca Sunova Owner's Manual

Look here for all of the manuals and diagrams that are available to you from Winnebago.

Winnebago Industries Manuals and Diagrams

[murraymcleod]

You say it works like the dash heater, meaning hot radiator water flows through a heat exchanger at the rear of the coach? And it will also heat up water in the hot water tank, when turned on?

[dbates]

I'm assuming it's like my 1999 Itasca. It's connected to your engine cooling system. Mine also heats the water heater. The wiring is for a blower to force the heat out. You should have a switch on your dash that will open the valve to it and turn on the blower. Although we have never used the rear heater it's great to have hot water available on the road and when you first set up camp.

Dave

[GPWayne]

Wish I had this on my rig. Heats just like you dash heat. Had it on my Winne gaser but not on the Winne DP. Oh Well.

[dougrainer]

The Chassis engine supplies the heat thru the coolant lines. Depending on the Model number of your water heater, the same coolant lines may also heat your water heater in transit also. If you give me the Model number of the water heater, I can answer that question. Doug