I Need help with new thermostat that I’m replacing... in 2010 Laredo 303tg

[hidefman]

I’m in desperate need of some technical help on my 2010 Laredo 303tg ...

I’m sitting here trying to replace the thermostat that the previous owner had put in with a coleman Mach 8330-336 .. the previous owner had what looked like a Honeywell thermostat meant for a house..

I hooked up all my wires from new thermostat to the existing RV wires .. color match them .. but here’s the kicker , when I switch to heat side it heats ... but when I switch to cool side .. I get NOTHING...

I spoke with a technician from a local camping outfit... but he to was stomped as to the wires that come outta the wall ..

Anyone on here have this model and could lend me a hand in what wires (from the thermostat side) are actually SUPPOSE TO GO TO WHICH WIRES coming out of the actual wall ..

I have the thermostat wires in a brown sleeve , and I have a set of red and black wires ... any help would be greatly appreciated.... thanks in advance!!!!!!

[ctbruce]

Maybe some pictures of what you are seeing would help us help you.

[jsb5717]

It would be very helpful to know what the original TStat was. If anyone has a similar rig can share pics of what they have. Even pull the cover and get a pic of their wires and share. I know that would help me.

Edit: Does the OP have his original manuals? You might have the one for your original TStat as a starting place.

[chuckster57]

Pull the ceiling panel off the AC unit and locate the control box. The connections will be labeled and your new Tstat should have instructions for wiring.

You can’t just go by “ this color is that” since you don’t know what was done in the past.

[hidefman]

Thanks for all your replies on here.. I’ll get some pictures later today if the wiring coming out of the wall.. and a picture of the Honeywell tstat that was in there as well.. along with the new Coleman tstat ..

I originally went by the wires that were coming out of the wall only because that’s what made sense.. but maybe the previous owner went and crimped them together red from wall turns into a white short wire that was previously in the Honeywell tstat etc...... pictures will explain this part when I post them..

[hidefman]

This is the old tstat



New Tstat
Attachment 1

Wires coming from the wall
Attachment 1

White wire turns into a gray wire from the thermostat wiring batch but rest stays the same
Attachment 1

Then I have a black and red looks like speaker wire size where the black turns into a white but the red stays a red
Attachment 1

And the rest of these aren’t used in the a/c unit either.. I have already confirmed that by removing the filter of the a/c unit
Attachment 1

And the tech thinks the one I’m installing now was what was originally in there... this was the only other manual that came with my camper Attachment 1

[hidefman]

In order from previous post .. don’t know what happened

[hidefman]

The red and black the tech says should be my +12 & -12 volt wire he’s figuring

[hidefman]

Does anyone know if that’s the correct thermostat I am putting in or is it the wrong model ???

Any input would be greatly appreciated

[chuckster57]

As long as your AC unit is Coleman Mach it should work.

[hidefman]

Originally Posted by chuckster57

As long as your AC unit is Coleman Mach it should work.

How do I tell what brand it is ???

[chuckster57]

It will say on the ceiling cover, or you can get in the roof and it might be on the cover. It will say on the data tag that is under both.

[hidefman]

Originally Posted by chuckster57

It will say on the ceiling cover, or you can get in the roof and it might be on the cover. It will say on the data tag that is under both.

It’s a Coleman Mach

[sourdough]

Originally Posted by hidefman

Attachment 21834Attachment 21835Attachment 21836Attachment 21837Attachment 21838Attachment 21839
In order from previous post .. don’t know what happened

What are the wires to in the top right picture? They appear to be the correct wires for your thermostat. Here is a link to the installation manual;

https://liferebooted.net/life-reboot...at%20Guide.pdf

Note the wiring diagrams. They begin on the right (page 4 - figure 1) then continue up on the left (page 5 - figure 1 continued). The colors for the wires for the 8330-336 and 8330-337 (heat and cool thermostats) are the colors in your hand in the top right picture. The instructions show where to put them on the unit.

[hidefman]

I spent a hr yesterday speaking to another tech , even sent him pictures of everything... and he couldn’t even understand as to why it was doing what it was doing... he said from pictures I sent him .. said it appears I have everything hooked correctly and the wires in the a/c unit matches what thermostat wires I have hooked up ..

I ultimately just decided to send it back to amazon.. figure something must be wrong with it since someone else had sent it back also.. lesson learned not to buy used electronics from them...

Just buying a brand new thermostat.. if that does the same thing then I know for sure.. just gonna rule out one thing at a time.. starting out with the used thermostat I bought

[chuckster57]

Lesson learned. I would never buy anything used from an online source. Anyway let us know what happens.

[hidefman]

Originally Posted by chuckster57

Lesson learned. I would never buy anything used from an online source. Anyway let us know what happens.

Will do.. thanks

[larryflew]

The usual problem is needing 2 power sources. 1 is 12 volt for your furnace and the other is 24 volt for your AC. Working from my phone so the pics are too small to be useful right now.

[chuckster57]

Originally Posted by larryflew

The usual problem is needing 2 power sources. 1 is 12 volt for your furnace and the other is 24 volt for your AC. Working from my phone so the pics are too small to be useful right now.

It’s all 12V in an RV.

[hidefman]

Ok... now something isn’t right with the camper.. just put the other thermostat back in that was originally in the camper and hooked up the wires per the diagram on it and heat works but now same issue.. no a/c .... it calls for cool but nothing happens.. ... I give up .. grrr