Water Heater Quitting Issue

WWFan · 11-28-2005, 05:30 PM

Hi All:

Lincster started a thread over on the alternate channel about his water heater quitting recently, and as I was reading it, I remembered that mine also quite while out at the Phoenix race a couple of weeks ago. All we did was take the unit out of the circuit and the heater fired right up.

I thought I would share my response, since it seems as though it maybe happening more often than not...

Here's the data that was on my Thermal Cutoff, which is what had blown (it's a single-use device):

Mfr: MicroTemp
???: SPKBRD
Type: G4A01
TF: 098*C

Here's a source, but I think you could get this from any electronics store (not Radio Shack)...Newark Electronics

I've got a local Able Electronics close to my office- I'll go there tomorrow. Oh...and BTW...did you see the price on a 1-24 pc qty? $0.833 each! Prolly could stock up about 10 of 'em and not break the bank! There have been rumors that WW or dealers charge upward of $30 or more for these fuses!!

Also...some good info on the unit itself from Emerson...http://www.emersonclimate.com/images/pdf/PDF-TCOs.pdf

If you have an inkling to solder the spades on the fuse, you will really want to read up on the connections section. It seems as though you might ruin the integrity of the unit if you get it too hot, but then again, the doc explains that a bad connection to the spades may increase the likelihood of the unit failing prematurely.

Hope this helps!!

Sean

WWFan · 11-30-2005, 05:55 AM

OK...got what I needed...NTE Part # NTE8096 from AbleTronics- bought 5 of them and along a package of .187" male & female spade connectors, I spend a whopping $12.46. We're all set!!

**RV Wizard** · 11-30-2005, 11:53 PM

THe reason the thermal fuses are there and probably blowing is the fire is rolling back out of the burner box. This can be a result of the box has an obstruction, the venture from the gas valve has an obstruction, the fuel to air ration mixture is not correct, or the gas pressure at the input of the gas valve is not correct. As long as the fire does not roll out and heat up this thermal fuse, it should never fail. It is a safety device to prevent burning up the coach from these previously mentiioned problems. Be sure to fix the problem and not just the symptoms. Good luck and be safe.

WWFan · 12-01-2005, 06:12 AM

Mike:

Thanks for the info- most of what we're seeing right now are on coaches that are only a few months old. I checked mine thoroughly before I replaced it- I'm wondering if it might be a placement issue- that fuse just dangles off a terminal just ouside and above the flume. and, of course, they could have the wrong setpoint on the thermal fuse, although I replaced it with the same that was on it. I also did a search, which alot of hits came back from the forums that suggest these things are somewhat suspectable to failure, but make everyone go hunting around looking at circuit boards, etc. I learned long time ago that the first thing you check are the fuses!!

Thanks again!

Sean

TH_NOOB · 12-01-2005, 08:34 AM

I think (with mine anyway)the failure was due to water getting inside the plastic sleeve... When I inspected it (before yanking it) I noticed standing water inside the sleeve....

WWFan · 12-01-2005, 04:44 PM

/Bob!

How the heck are ya? That may be the case...I had a white spot inside the clear tubing that could have been some very mineralized water, but I really think the back end of the TCO blew out.

Did you get some backups?

Sean

**RV Wizard** · 12-01-2005, 11:54 PM

Water will not impose a problem for these thermal fuses. They are temperature rated and designed to open when the ambient temperature reaches the set point of the rating. I have seen water heaters over ten years old with the original thermal fuses still intact and good. For some reason the most common problem I have found in the water heater venturi tube has been very small spider webs. The tubing must be the perfect size for these pest to make a home in. The webbing is so fine I can only see them in high humidity but if you will remove the venturi tube and run a bottle brush just the size of the tubing through it, this will ensure that there are no obstructions to cause the flame to not be correct, and believe me those fine webs WILL make a difference. I too have a supply of electronic parts house issued thermal fuses and 1/8" male and female spade connectors for when needed.

TH_NOOB · 12-02-2005, 07:03 AM

Quote:

Originally posted by RV Wizard:
Water will not impose a problem for these thermal fuses. They are temperature rated and designed to open when the ambient temperature reaches the set point of the rating. I have seen water heaters over ten years old with the original thermal fuses still intact and good. For some reason the most common problem I have found in the water heater venturi tube has been very small spider webs. The tubing must be the perfect size for these pest to make a home in. The webbing is so fine I can only see them in high humidity but if you will remove the venturi tube and run a bottle brush just the size of the tubing through it, this will ensure that there are no obstructions to cause the flame to not be correct, and believe me those fine webs WILL make a difference. I too have a supply of electronic parts house issued thermal fuses and 1/8" male and female spade connectors for when needed.

Shows ya how much I know.. No, Sean I have not been able to gather some of them up yet though armed with all the good info you've given me I will be sure too soon....
\Bob - out

WWFan · 12-05-2005, 04:30 PM

Hey /Bob:

In case you don't get around to getting some, I'll give ya a couple of mine next time we run into each other...

Sean

FYRMAN · 12-15-2005, 06:51 PM

Quote:

Originally posted by RV Wizard:
For some reason the most common problem I have found in the water heater venturi tube has been very small spider webs. The tubing must be the perfect size for these pest to make a home in.

They are the perfect size, and insects love the smell of LP, which draws them in.

WWFan · 12-15-2005, 07:10 PM

Hummm...maybe we outta petition the LP companies to add some 'stinky' to their mixes!

Naykid · 12-23-2005, 09:43 AM

Another thought, I had trouble with my last TH in the wind, the wind would blow back through teh combustion vent and create a similar condition to flame roll out which is what that thermal fuse is there to protect against. Since we often encounter high winds in the des and usually park with the heater headed into the wind I built a sheet metal cover that snapped into a pair of clips over the combustion vent. You must size it to match the opeining in the vent so there is no restriction. It worked like a champ. Haven't had the problem with the new Rage'n yet but if I do I'll build another, gave the original to the new owner.