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Topic: Water Heater Red Warning Light Stays On (Read 399 times) previous topic - next topic
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Water Heater Red Warning Light Stays On
Couple of weeks ago, I got my LD out of storage for the first time this year and headed for Big Bend NP. We have worked out how long to heat the water in order to run only hot water for a shower at a comfortable temp, rather than trying to mix hot and cold. The first night, my wife discovered that the water was much cooler than expected after heating it our normal time. And I noticed that the red "Check WH" light at the switch stayed on the whole time, rather than shutting off when the heater was lit. When I checked the heater flame, it was orange-yellow, not blue. Not sure why it was out of adjustment (the set screw holding the air shutter in place seemed tight), but I moved the shutter a bit to get a blue flame, and that solved the water heating issue. When we got home, I ran a brush through the burner tube to see if there was a spider web or other debris in it but found nothing.

So the heater seems to be functioning normally again, except that the red light still remains lit as long as the heater switch is on. Anyone have any ideas about why the red light stays on? If the water heater continues to light and perform OK, is there a downside to just ignoring the red light?
Doug R
Formerly 2007 23.5 Front Lounge

Re: Red Water Heater Light Stays On
Reply #1
That's a new one for me.
There is slight chance the spark gap is off. The spark gap is used to determine if there is a flame and, if so, the propane valve will stay open past the initial ignition period.
Beyond that, I would suspect the control board is bad.
Swapping in a spare control board is the only positive way I know of for testing this.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: Red Water Heater Light Stays On
Reply #2
The problem light will play on my mind until fixed. !@#$%^&*())+. 

There is to much risk in that problem  in my mind.
Rodney
1988 Mid Bath

Re: Red Water Heater Light Stays On
Reply #3
Couple of weeks ago, I got my LD out of storage for the first time this year and headed for Big Bend NP. We have worked out how long to heat the water in order to run only hot water for a shower at a comfortable temp, rather than trying to mix hot and cold. The first night, my wife discovered that the water was much cooler than expected after heating it our normal time. And I noticed that the red "Check WH" light at the switch stayed on the whole time, rather than shutting off when the heater was lit. When I checked the heater flame, it was orange-yellow, not blue. Not sure why it was out of adjustment (the set screw holding the air shutter in place seemed tight), but I moved the shutter a bit to get a blue flame, and that solved the water heating issue. When we got home, I ran a brush through the burner tube to see if there was a spider web or other debris in it but found nothing.

So the heater seems to be functioning normally again, except that the red light still remains lit as long as the heater switch is on. Anyone have any ideas about why the red light stays on? If the water heater continues to light and perform OK, is there a downside to just ignoring the red light?
Doug, I would clean all the contacts on the control board with contact cleaner. It can't do any harm.
Chris
Formerly: 2002 30' IB

Re: Red Water Heater Light Stays On
Reply #4
Doug, the advice above sounds good.  The red light is on when the system is checking its status and initiating startup.  Normally, if there were a problem starting, the system would try to start three times, with the red light on, then shut down.  Since your red light is staying on but the system is heating, that suggests a board problem to me.  Were the sensor failing to detect ignition, a properly functioning board would shut off the propane.  Thus, even if there is a problem with the spark gap or the ignition sensor, there is likely also a problem with the board.

Before you replace the board, follow Chris's advice and clean all the contacts, not just the ones on the board, but every spade connection in the wiring as well.  If, at that point, you still have a red light that is staying on, that is not a trouble mode that I am familiar with, nor is it mentioned in Atwood literature that I have reviewed.  So, why not give Atwood a call and see what they have to say?  I DID find a discussion about this on another board.  The poster stated, "In days of old the light used to stay on to indicate the heater was running in propane mode. Then Atwood changed the design so that the light went off after ignition was verified - guess they did not want to confuse folks with a red light that meant OK. Easier to turn it off then to make it a green light, I guess. Anyway, if this is a pre about 1998, having the light stay on may be normal."    I have no idea if this is accurate, or if it is applicable to you, but I note it in passing.

Assuming you need a new board, they are easy to install, but give some thought to putting in a Dinosaur board rather than an Atwood board.  Andy Baird was an early trumpeter of the better quality of the Dinosaur boards, and I have had one in my system for many years.


Ken F in NM
'08 MB

Re: Red Water Heater Light Stays On
Reply #5
Are the Dinosaur boards a direct replacement with no mods necessary?
Greg & Victoria
2017 Mid-Bath  “Nocona” towing a manual 2015 Forester
Previously a 1985 TK
SKP #61264

Re: Red Water Heater Light Stays On
Reply #6
When I replaced mine with a Dinosaur board I had to drill one hole, as Andy described in his great article now found on he Companion. He does warn to NOT drill into the water tank. I had. Problem avoiding this. All that said (written), it may be a very low cost job for an RV tech. It should take well under an hour.
Paul
'92 Mid Bath

Re: Red Water Heater Light Stays On
Reply #7
Are the Dinosaur boards a direct replacement with no mods necessary?
The Dino board, in our 2003 LD, is a direct replacement, when used with their adaptor plate and plastic cover.
Takes less than 15 minutes to install.

Amazon.com: Dinosaur Electronics (UIB S) Small Universal Ignitor Board:...
Amazon.com: Dinosaur Electronics 2TABMOUNTK Tab Mounting Kit: Automotive

Larry
As an Amazon Associate Lazy Daze Owners' Group earns from qualifying purchases.
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: Red Water Heater Light Stays On
Reply #8
In my 2008, it was a direct replacement, no drilling needed.

Ken F in NM
'08 MB

Re: Water Heater Red Warning Light Stays On
Reply #9
I really appreciate all the feedback from everyone. I'll check the gap and clean contacts. If the problem persists, I'll order a new board.
Doug R
Formerly 2007 23.5 Front Lounge

Re: Water Heater Red Warning Light Stays On
Reply #10
Hi Larry,

When ordering does the tab kit come with the cover or must one order it separately?  In the picture, it looks as though the cover comes with it so you only need two items as you listed, the board and kit.  However, Amazon shows a separate cover to be ordered along with it.  Please confirm two items as I just placed an order.

Gary
2007 30' TB

Re: Water Heater Red Warning Light Stays On
Reply #11
I would check the color and character of the flame at the stove and furnace, too. If they are off, then you may need to check your gas pressure, or you may have had a bad fill.

Steve
2004 FL
2013 Honda Fit

Re: Water Heater Red Warning Light Stays On
Reply #12
When ordering does the tab kit come with the cover or must one order it separately?  In the picture, it looks as though the cover comes with it so you only need two items as you listed, the board and kit.  However, Amazon shows a separate cover to be ordered along with it.  Please confirm two items as I just placed an order.
It has been several years and I'm not sure. It sure looks as if the cover is included with the mounting plate.
If it isn't, Amazon Prime will deliver it in a couple days.
The water heater can temorarily be operated without the cover.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze

Re: Water Heater Red Warning Light Stays On
Reply #13
I had to order the cover separately
Paul
'92 Mid Bath