Electrical component identification and wiring help

Thanks for the replies, I was traveling in NC the last five days.

Yes, I have the heater in the water bay. I rewired the 12V bay heater and it now has it's own temp disc switch. I'll do some continutity switches to figure out the wiring. Thanks for the info!

I looked at his water bay pic and YES, the heater is there. Doug

The pic of the snap disc shows 3 wires. BUT just one has a spade terminal. That goes on either side of the Disc. The other 2 do nothing. He needs to look at his heater and follow the wires from the heater. ONE will be ground, probably white. The OTHER will be longer and have another spade terminal and THAT will connect to the open pin on that disc. It got pulled loose somehow. Doug

Cold Weather Use
The motorhome is not designed for extended use in below freezing (32°F/0°C) weather. There are
precautionary measures that can be taken for extended cold weather use.
Interior water lines, fixtures, and drains above the floor are normally protected from moderate freezing
temperatures as long as the furnace is operating.
Cold temperature can adversely affect water systems below the floor level because the furnace heat does not
provide heat to these components.
A bay heater with a “Snap Disc” thermostat is used to heat the water control bay.
System Operation:
1. Systems heat switch is turned ON to apply power to the snap disc thermostat and bay heater.
2. When the bay temperature reaches 40º F +/-6º F the snap disc thermostat closes, applying power to the
bay heater. The systems heat active indicator light will be lit. The twelve-volt heater continues to operate
until the bay temperature reaches 55º F +/-6º F. The indicator light will then turn OFF.
Exposed drains and water lines may freeze quickly in below freezing
temperatures. If, by the way of prior experience, there is doubt as to what
temperature the motorhome water system tolerates and the water system
will not be used, winterize the water system using potable antifreeze. When
the tanks are dumped, additional potable antifreeze needs to be added to the
storage tanks.
WARNING:
The battery disconnect switches must be turned off if the
motorhome is left for an extended period of time (2 hrs). The
battery cut-off switch does not control the bay heater circuitry.
NOTE:
The heat system quickly drains the motorhome batteries when not
connected to shore power or operating from the generator. Only
use the heat functions when hooked to shore power or operating
from the generator

Link to manual Page 197 Pic of heater page 180

https://big.nyc3.cdn.digitaloceanspaces.com/revgroup/general/2006_Endeavor.pdf?mtime=20201116162855&focal=none

Test the wires to a good ground for 12 volts DC. Turn on heater switch.
Test each wire, not having power to ground for a resistance.
If heater is present, you should have resistance.
Test the thermostat for continuity. It should be open this time of year. I am guessing it will not close above 45-50 degrees ambient air temperature. If you remove it, you should be able to see values etched into silver portion.

larry cad wrote:

dougrainer wrote:
The is a Temp disc for the electric 12 volt heater in the Wet Bay. You turn on the inside bay water heater switch and WHEN the temp drops below 34 degrees the heater comes ON. Doug

To test it I use a standard PC compressed air can upside down and freeze the disc to verify the electric heater does work thru the disc. 15 years old it may not still work.

Doug, his problem is which of the three wires in the harness should be connected to the two connectors? Looks like he has the red one connected, leaving the blue and yellow to decide on.

Well, after looking at his water bay pic, I do NOT see the 12 volt heater. The OP needs to state if he is the original owner. It appears the Heater has been removed in the past 17 years. Hence the wires not connected to the Temp disc. IF NO heater, then the wires do nothing. Doug

dougrainer wrote:
The is a Temp disc for the electric 12 volt heater in the Wet Bay. You turn on the inside bay water heater switch and WHEN the temp drops below 34 degrees the heater comes ON. Doug

To test it I use a standard PC compressed air can upside down and freeze the disc to verify the electric heater does work thru the disc. 15 years old it may not still work.

Doug, his problem is which of the three wires in the harness should be connected to the two connectors? Looks like he has the red one connected, leaving the blue and yellow to decide on.

The is a Temp disc for the electric 12 volt heater in the Wet Bay. You turn on the inside bay water heater switch and WHEN the temp drops below 34 degrees the heater comes ON. Doug

To test it I use a standard PC compressed air can upside down and freeze the disc to verify the electric heater does work thru the disc. 15 years old it may not still work.

Thanks for the help. Looks like a thermister to me. I guess it could be measuring something for system heating??? It's not mounted on any of the water tanks, it's above them. My dilema is that I have three wires and only two terminals. I know the red terminal goes to one terminal.

I got everything (except this wiring) back together yesterday. Found out that I need a new rubber washer for one of the water lines. I might try it and see what doesn't work...

The blurry device on the left is an Intellitec pump controller, the round device on the right, with no wires connected, looks like a thermodisc for checking temperature (like the ones on Atwood water heaters for monitoring water temperature). If it is a thermodisc, it doesn't matter which way you connect. If it is a thermodisc, what temperature is it monitoring? Just curious.

I forgot. The bulletin board will not allow "permalinks" from Gdrive because they do not end in ".jpg" This works on other bulletin boards I forgot. The bulletin board will not allow "permalinks" from Gdrive because they do not end in ".jpg" This works on other bulletin boards Permalinks for Google Drive Images

OP the first picture is too blurry for me to give advice.