Norcold N611VLW6 Fridge issues.

[kendive]

We just bought a brand new 2016 Coachman Catalina 253 RKS and it has the Norcold fridge in it. Now I had had issues with other campers where I had to install fans on the top vent to help the fridge keep cool but now I have the opposite problem.

The Fridge gets too cold...

I know and have read all the cases of this on here and other sites so I ordered and have had good luck with them in previous campers the Snip-The-Tip for the Norcold model I have and cut the thermister off and installed it thinking this will fix the issue. Nope...

I emailed Snip-The-Tip with a pic making sure that I did indeed get the proper one since on there site they show some that have a 5K ohm and one with a 10k ohm sticker on them. They emailed back stating that I had the correct one and there product is hit or miss on these rv fridges. I was floored because I always loved there product and it just worked. They also said that the control board could cause this issue. I know I could let the RV dealer to look at it but I'm not like that... So I ordered a new control board for this unit and installed it with the snip-the-tip still installed. Same thing still gets too cold with no control of the temp in the fridge area.

I have bought a new thermister and clip since dumb me threw that away thinking it would never be needed again.

That is where I am at. I have not tried putting the new thermister and clip back in place on the 10th fin over from the left and do a test run.

I'm just not confident that this will fix the issue and boggled on what it could be if no the control board or thermister?

Oh I wanted to add that all my testing has been with the AC Plugged in and I have not ran the fridge on gas yet... Something to try later.


Here are some pics to help out...

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Snip-The-Tip



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Original Control Board (Yes the Ground and 12VDC wires are removed in this pic)




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New Control Board

[Bama Rambler]

It sounds like the fridge is in backup mode.

Did you ice water test the thermistor and/or snip-the-tip at the board connector to see if there may be a break in the wiring?

If there is a break or bad connector, you'd have a problem with both the thermistor and the snip-the-tip even after changing the control board.

[kendive]

Originally Posted by Bama Rambler

It sounds like the fridge is in backup mode.

Did you ice water test the thermistor and/or snip-the-tip at the board connector to see if there may be a break in the wiring?

If there is a break or bad connector, you'd have a problem with both the thermistor and the snip-the-tip even after changing the control board.

I did not try to do the ice water test yet. Yes I was thinking that I may have a break in a wire somewhere and will check that next.

Here is what the snip the tip folks wrote back to me when I asked if I had the proper one.

The 611 sadly can be a hit or miss with our product. 95% of them will
work and 5% won't. We suspect it may be a board to board issue of the
controller. That is most this stuff is mass reproduced in China and
some fab houses change specified parts to cheaper version or whatever
they have in stock. That doesn't mean it won't work with a newer OEM
thermistor. Our part is slightly different from the default, so when
this stuff happens the best course is to try an OEM thermistor
replacement first, and if it works then just stick with it. the 10
versus 5 is really just to offer more dynamic range of adjustment with
the 10.

[kendive]

Well I have had some more time to mess with the Fridge to cold issue.

I ordered a new thermistor and installed it with the clip on the fins. Still just stays way to cold.

I now have the camper all off AC and DC sides and removed the connector P2 off and put a meter on points 1 and 6 that go to the thremistor. At first I got around 33k Ohms and then put the Thermistor is ice water and watched the ohms drop to around 31.5. So I do believe that the Thermistor and related wiring is working great.

Update: Just put my hand around the thermistor for a little bit and got the Ohms down to around 18K.

So what else could be causing this fridge to be in backup mode?

P.S. I have not tried running the fridge just on gas...

[Bama Rambler]

When you got 33,000 ohms, was the thermistor in the cold fridge?

About the only thing left is the display board. You've pretty much changed everything else.

[kendive]

Originally Posted by Bama Rambler

When you got 33,000 ohms, was the thermistor in the cold fridge?

About the only thing left is the display board. You've pretty much changed everything else.

Yes the Higher Ohms was where the Thermister was colder.

I agree that the display board is the only thing left but I just don't see it being the issue...

Here are some pics of it.