NOW..........NO HOT WATER AT ALL!!!

[Fosters]

Re: Suburban WH type

2nd owner to my 5th that has dual HW heating and not a single piece of repair history before I bought it in June 2016. Anyhow, I got hot water both by LP and elect with no problem till now, Jan 2017.

I prefer to use Electric mostly, and suddenly no hot water. Switched to LP and firing hot water, no problem. But I had to of course, find out why the elect was not working any longer. I am a DIY'r as best as I can. So with Dr. Google and youtube I tried to self teach myself on the use of a multi meter. I found the resistance only @ .10 for the heating element, which online mechanics tell me "that it is good". Anything higher then like .20 they say is bad.

So next is the thermostats, and visually both look. Meaning no obvious burnt outs or disconnects in either of the 4 fasteners. And I am aware, that the lt blue 2 on the LF are elect and the pink 2 on the
RT are gas. What should the resistance be on the thermos?

So I went ahead (before the meter check) and bought a replacement heater element and anode rod as well. I replaced the anode rod and glad I did (for assuming the original was still installed, now 8 years later and very well sacrificed for the job intended!). But I could not get the heating element out as I do not have a 1 1/2" socket. But again, the meter test indicates that is not the problem anyhow. But I want to check "how eaten up" it is anyway (have the replace part as well)?

What am I missing?

And get this, and salt in the wound, I put everything back together and NOW I CAN'T EVEN GET HOT WATER WITH THE LP SOURCE!!! Forget about the electric for a 2nd. The LP gas channels thru the pipe all the way to the what is it called "thermocoupler" (the part with the 2 prong arms that hang over the pipe) and ignites it right? Well, she flames up for 5 secs and shuts down. Then, repeats 2 more times (as I have also read, a total of 3 times try). So why won't the LP gas stay lit and heat up the water tank? And yes, full tank of LP and full strength of LP flow.

Please help, for now I have no HOT Water either LP or Electric!
Thanks in Advance and I hope I can answer questions to repair the problem or problems.

[j-d]

Joe417 wrote:
Ours (the Control Module) is mounted about a foot to the left and above the water heater. Directly behind the cabinet drawers.

Water heater is directly below the sink.

Same here. Trace four wires or so from the 12-VDC Junction Box (upper left corner of the water heater looking from inside the coach) to a plastic box about the size of a package of 3x5 recipe cards. Our box is white, with a small raised round section on top, an edge-mounted terminal for those wires from the 12-VDC box, and the red-orange ignitor wire also comes out of that box. Upper left is the logical spot, since it's near the junction box and where the ignitor cable goes into the heater. Ours is held with one screw to the inside wall of the coach.

[Joe417]

Ours is mounted about a foot to the left and above the water heater. Directly behind the cabinet drawers.

Water heater is directly below the sink.

[Chris_Bryant]

The circuit board is shipped loose, it's up to the installer to decide where to mount it, but it will be within 24 inches or so. It comes with doubles sided tape, or screw holes to mount.

[j-d]

I looked this morning and didn't find anything that looked like it covered a logic board near the rear (inside) end of the water heater. Now I need to find that out, for myself and anybody else in the future. NO indication of a board or cover for a board, I hope it's not under that foam shell...

I'll find the service manual and see if it shows more than the Parts List.

[j-d]

I think all these "SW" sizes are set up about the same. Will look at ours tomorrow morning. From what I can tell, the Module is in a cover at the back side of the WH. By that I mean the rear of it, the part extending farthest into the interior of your coach.

[westend]

Here is the manual with a parts list and exploded diagram of the SW 12E. You can see that it has a "module board" and the exploded diagram in the parts list depicts it's location.

[Fosters]

Does my Suburban system have a circuit control board like the furnace? For the furnace control board is clearly visible and accessible from the outside door panel and I have already replaced it.

But what about the HWH and as I need help with here today. So if it has a board, then it is not visible or accessible from the outside door panel. So if one, where is it and can a DIY'r get to it to check it out?

[Fosters]

Nope, by-pass has not been touched. But thank you.

[hawkeye-08]

I'll share a quick story,
We sold our previous trailer to wife's nephew. His wife called one night while they were camping at county fair (kids showing steers) to find out how to get hot water... told her the switch to ignite was in the corner by the sink.. she could hear it trying to ignite so thought all was good. I found out later that still no hot water.. I was taking a shower at home a couple days later and wondering if they dewinterized it? They had not, still in bypass mode, no water going into hot water heater.

Has someone been messing with your bypass valve ?

[Old-Biscuit]

Electrode needs to be 'engulfed' in main flame....should glow red

Ceramic.....fire up WH at night in the dark and if cracked you will see it 'tracing' to ground

Burner tube....needs to be 'aligned' so that gas flow is directly down the center of tube. If cocked gas will bounce off walls of tube and not properly mix with air being pulled in thru air shutter.
Fuel/air ratio is very critical especially since propane is at such low pressure (11" WC----that is roughly 0.4 psi)

Thermo LP spades........just make sure good/clean-tight connections
Test that you are getting 12V DC thru them.

[Mandalay_Parr]

They have to be in the flame.
Jerry

[Fosters]

Suburban Model is # SW12DE btw.

Mandalay & Old-Bis (others of course!), following both suggestions. 1st being retrace my steps of what I disturbed and 2nd, did I disturb the electrode placement?

On the Thermo LP spades, I noticed that they were flopped up and I thought out of place? So I depressed them back down parallel (just like the Elect spades). Was that a no-no? Would it make a difference?

Next, when replacing the gas pipe it was very stubborn to line that one bolt back into the "frame lined hole" so I placed a screwdriver on top of the pipe and kinda pryed it down and shimmied into place. Perhaps I disturbed the path and correct position of the 2 electrodes? Are they supposed to be heavily engulfed into the flame or just hoovering over the flame? I will have to look, but certainly hope I did not crack the ceramic on the electrode body? That should be visible yes? But assume it would fall out if so? But putting that aside, interested in the electrode placement right now?

[j-d]

The problem on the 120 VAC side was the WHITE (neutral) wire from the Element, back to the Coach Wiring, was open at the junction box I mentioned earlier.

It had been lighting on LPG, but not every time. While I was working on the water heater, I inspected the Electrode Assembly. Since it looked good, I didn't replace it. But I DID clean the ground connection and re-install with an anti-corrosion compound on the screw. The diagram doesn't show a GROUND on that assembly, just the "spark plug wire" from the Board, but it needs ground to work.

[Old-Biscuit]

Suburban uses a very simple circuit for electric and for propane
AC/DC Junction boxes are on backside of WH.....one each side

Electric..
120V AC from Main Power panel via a Circuit Breaker
From CB to On/OFF Switch
From On/Off Switch to t-stats (Left set)
(High Temp then via connector wire to Normal temp----HI has 'manual reset push button)
From t-stats to element (black wire) then to Neutral (white wire)

Follow the 120V AC VOLTAGE ---find where you loose it



Propane.......
12V DC from Dist Panel via FUSED circuit
TO On/Off Switch to t-stats (Right set) SAME as 120V Hi/normal
From t-stats to Circuit Board (rear corner of tank)
From Circuit Board to GAS valve (Brown wire---then to ground) and to SPARK Electrode (Heavy Orange wire)




Spark electrode fires igniting propane
Propane flame then 'ENGULFS' spark electrode generating a signal that goes back to circuit board 'PROVING' main flame lit (no signal...shutsdown)

Electrode is firing/main flame lites
so Check electrode position (engulfed in flame)
Check electrode CLEAN (no sooting/carbon...otherwise no signal)
Check spark electrode ground (assembly mounting screw...clean/tight connection)
Check electrode ceramic ....no carbon/cracks otherwise signal will track to ground
Check that electrode high voltage wire connection is clean/tight


Also check that both High Temp T-stats are not tripped.Push button in to reset