The heater hose that feeds the heater coil for the dash heat has been plugged up by the prior owner because there was a leak. (It's plugged in the front of the RV by the heater coil.)It looks like the heater coil received it's radiator fluid feed from the Engine Sending Unit. (Radiator fluid through Sending unit on it's way to heater coil)Since there is no flow to the heater coil I assume there is no flow through the Engine Sending Unit?Could this cause inaccurate water temp readings on my gauge?I have been getting inconsistent higher than normal temps on my gauge.Thanks for your help.Jeff '98 Monaco Dynasty - Cummins C-Series: 6 C 8.3 Engine Turbo - Side Radiator

That "sending unit" might not be what you think it is.Either way, cutting out part of the circulation loop like that will decrease your cooling capacity slightly......and of course will give you NO heat in the cab. You really should get it fixed.

Post a piture of the "sending unit" so we can identify it. I have never seen a configuration with the engine coolant sensor in a heater line....

http://share.shutterfly.com/action/welcome?sid=0KctWzhy3auag

Maybe it was plugged because the heater core had a leak. Some of them not easy to get at and replace.It shouldn't have anything to do with engine cooling. That circulation is shut off on all when using AC only.1. Your radiator/CAC may need cleaned. 2. Thermostate replaced

It comes from somewhere goes into and out of the heater core, exits the cab then enters the engine cooling system "somewhere".Mechanical coolant shutoff valves are so rare that when I had a Willys Pickup back in the sixties I had to settle for a mechanical flow shutoff valve from a RAMBLER. Today's systems use chambers and trap doors to divert or block off air for A/C and heat as needed.Returning to paragraph one. Search for and find the 2nd plugged hole in the cooling circulation. Purchase a couple of nipples, hose and clamps and satisfy your own curiosity as to whether this is the issue. If the core leaks, bypass it.

Disconnected heater hose & engine high Temp ? | Good Sam Community

Vulcan_Rider
Explorer
Aug 24, 2015
That "sending unit" might not be what you think it is.

Either way, cutting out part of the circulation loop like that will decrease your cooling capacity slightly......and of course will give you NO heat in the cab. You really should get it fixed.
sch911
Explorer
Aug 24, 2015
Post a piture of the "sending unit" so we can identify it. I have never seen a configuration with the engine coolant sensor in a heater line....
cotten31
Explorer
Aug 24, 2015
http://share.shutterfly.com/action/welcome?sid=0KctWzhy3auag
Triker33
Explorer
Aug 24, 2015
Maybe it was plugged because the heater core had a leak. Some of them not easy to get at and replace.

It shouldn't have anything to do with engine cooling. That circulation is shut off on all when using AC only.

1. Your radiator/CAC may need cleaned.
2. Thermostate replaced
MEXICOWANDERER
Explorer
Aug 24, 2015
It comes from somewhere goes into and out of the heater core, exits the cab then enters the engine cooling system "somewhere".

Mechanical coolant shutoff valves are so rare that when I had a Willys Pickup back in the sixties I had to settle for a mechanical flow shutoff valve from a RAMBLER. Today's systems use chambers and trap doors to divert or block off air for A/C and heat as needed.

Returning to paragraph one. Search for and find the 2nd plugged hole in the cooling circulation. Purchase a couple of nipples, hose and clamps and satisfy your own curiosity as to whether this is the issue. If the core leaks, bypass it.
sch911
Explorer
Aug 24, 2015
cotten31 wrote:
Here is the picture.
Here is a link

https://www.dropbox.com/home/Jeff?preview=RV+Sending.JPG

You need to use the public link to your pic. What you have requires a login...
beemerphile1
Explorer
Aug 24, 2015
The line shouldn't be plugged. Typically the heater core is bypassed by extending the hose from the output port to the return port.
Vulcan_Rider
Explorer
Aug 24, 2015
Triker33 wrote:
That circulation is shut off on all when using AC only.

NOT true with many/most recent models, where the AIR circulation through the heater core is diverted but the hot water flows ALL the time.
cotten31
Explorer
Aug 24, 2015
Try this link. I hope it works

http://share.shutterfly.com/action/welcome?sid=0KctWzhy3auag
cotten31
Explorer
Aug 24, 2015
sch911 wrote:
cotten31 wrote:
Here is the picture.
Here is a link

https://www.dropbox.com/home/Jeff?preview=RV+Sending.JPG

You need to use the public link to your pic. What you have requires a login...

Try this one.

http://share.shutterfly.com/action/welcome?sid=0KctWzhy3auag