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dieterdog · 04-24-2007, 06:49 PM

Basic question then,, after all of the above is read and digested,,, is this fix a real fix or just a precaution for Dometic??? How safe are the models that are affected??? am quite concerned,,, thanks,, donna

lewster · 04-24-2007, 08:09 PM

I won't really know until I get my first recall kit. Itd's impossible to say at this point, but I'll post as soon as the first one arrives.

Hopefully, they will get here soon, as I'm getting a lot of calls on this and have NO PARTS YET

HowieE · 04-25-2007, 08:55 AM

The "Kit" was installed in my trailer last Saturday. It is a joke. All the "Kit" consists of is a Limit switch wired in series with the 12 volt supply line for the refridgerator control board and some sheet metal pieces that were not even used in my case. There is no lower wattage electrical element. Nothing to reduce any eventual metal failure that would release the Hydrogen gas.

Now lets just think about this for a second. If you have a crack failure in the refridgerator system that releases Hydrogen gas that has then been ignited to produce enough heat to trip the high limit switch do you real think cutting off the power to the refrigerator is going to do anything. Oh yes and by the way the only way you would know the system has failed would be the lights on the monitor of the refridgerator would go out or you would smell the smoke

There are 3 ways to put out a fire. Lower the temperature, cut off the fuel, cut off the oxygen. This system does none of them. I would assume all Dometic has done is ackowledge a problem and provide a blantanly inadequate solution. Not sure I would want to be thier insurance carrier.

Is there any indication that the newer units are any better or have they just installed the limit switch in them at the factory?

dieterdog · 04-25-2007, 10:42 AM

Howie,, great question,, i too am awaiting the same answer,,, thank you for posting,, donna

lewster · 04-25-2007, 06:58 PM

As I have stated in previous posts, I have not seen the kits yet. That said, when they were initially described to me by Dometic Tech, the extra sheet metal was to be used as another location for the heating element to be positioned. There also was to be a 'shield' that would re-direct any potential leak of hydrogen coolant away from the element, thus decreasing the possibility of ignition and fire.

From what I was told...ALL OF THE PARTS SHOULD BE USED IN ALL INSTALLATIONS! HowiE, I would go back to your installer and ask them point blank why they didn't install the extra sheet metal, and if they insist that it should not be used, ask to see the Dometic instructions that directed them to do so.

HowieE · 04-25-2007, 08:36 PM

I saw but did not study the 4 or 5 pieces of flat sheet metal in detail. The installer said they were optional depending on the model. The larger piece was to be installed in a place that my refg. already had an equal sized piece of sheet metal. He used mine because it had the drain hose going through it. The only metal he did use was the holder for the limit switch.

We did discuss what a joke the kit was. When he had originaly heard about the problem he had assumed the complete cooling system would have to be replaced since the kit does nothing to reduce the mechanic failure that would cause a leak and less to supress a fire. All it does is shut of the 12 volt supply if the temperature behind the refg. gets too high. If that temperature rise is the result of a fire you have already lost the game.

Oh yes the only indication you get, other than a fire, is the fact that the control panel light will go out.

Yes I would be interested in seeing the instruction.

If Hydrogen gas escaped into the heating area of the refg. no sheet metal would have any effect.

As one of our posters notes at the end of all his posts.

"The Ark was built by amatures the Titanic was built by profesionals".

This "Kit" has all the ear marks of another professional job. Don't let your insurance laps.

Fyrzowt · 04-26-2007, 12:25 AM

The ark may have been built by an amateur, but don't forget - he was using God's blueprints.
Dave

TomW · 04-26-2007, 04:48 AM

Quote:

Originally Posted by RV_cool

[IMG]... To my knowledge I'm the only rebuilder in the states that uses helium. It's twice as expensive as hydrogen but it's worth the safety.

From what I know about RV refigerators, I read that comment thinking that hydrogen was used because it had better physical properties than helium for use in gas absorption applications and NOT because it was cheaper. Part of my mindset came from having never thought about using helium until RV_cool mentioned it. It appears that helium, in addition to being safer, is actually beter:

Quote:

Originally Posted by Numerical investigation of a diffusion absorption refrigeration cycle

Abstract

A thermodynamic model was developed for an ammonia–water diffusion absorption refrigeration (DAR) cycle with hydrogen or helium as the auxiliary inert gas, manufactured by Electrolux Sweden (currently known as Dometic). The performance of the system was examined parametrically by computer simulation. Mass and energy conservation equations were developed for each component of the cycle and solved numerically. The model was validated by comparison with previously published experimental data for DAR systems. Investigation of cycle performance under different conditions indicated that the best performance was obtained for a concentration range of the rich solution of 0.2–0.3 ammonia mass fraction and that the recommended concentration of the weak solution was 0.1. It was also found that as the degree of rectification decreased, the performance of the DAR cycle decreased. Finally, the study showed that helium was superior to hydrogen as the inert gas: the coefficient of performance of a DAR unit working with helium was higher by up to 40% than a cycle working with hydrogen.

Live & learn.

Tom

RV_cool · 04-26-2007, 09:48 AM

Quote:

Originally Posted by Silvertwinkie

Lew, it sounds to me like the main goal here is fire suppression, not prevention in the event of a tube crack caused by the higher wattage heating element.

My question is about the cost of helium to be placed into these units. It sounds to me that at some point, there is a higer than average chance these units involoved in the recall will fail at some point. If that is the case, maybe it would be a great idea to do the right thing when it comes time to rebuild the unit? Is it cost effective to drain the hydrogen somehow, without blowing yourself up and installing helium before it's an issue?

What would an average person expect to pay for a fridge, pre-failure to have the hydrogen removed and replaced with helium?

I'm currently in the process of releasing a automatic fire supression system for RV refrigerator compartments. This kit is easy to install and will retail around 70 - 75 dollars. No need to remove fridge for installation. The paperwork has been summited and I'm just waiting for the US Patent office to send me the provisional patent receipt. How many people would be interested in a system like this?

TomW · 04-26-2007, 03:13 PM

Without giving away sensitive patent info, can you give an overview of your idea's operation?

Tom

RV_cool · 04-26-2007, 10:41 PM

Quote:

Originally Posted by TomW

Without giving away sensitive patent info, can you give an overview of your idea's operation?

Tom

If I did I'd have to kill u (just kidding) no can't release any details at this time, but it will be effective in a fire and can be removed and transfered to another RV if somebody say bought a new one and wanted to transfer it. All you need to install is a screwdriver, pliers, and a wire cutter.

Silvertwinkie · 04-27-2007, 06:35 AM

Without question yes. Cost would be an issue (I could see $70-$75 for a working solution a great price point though), but yes, I'd be very interested. I'd even offer to be a beta test if I didn't have to ignite my fridge compartment to set it off!

dieterdog · 04-27-2007, 07:31 AM

Am interested also,, need easy installation directions though,, thanks,, donna

RV_cool · 04-27-2007, 10:21 AM

Quote:

Originally Posted by dieterdog

Am interested also,, need easy installation directions though,, thanks,, donna

working on the instructions now, it may be until next week till I get them done. I can say you install it from the outside of the coach thru the vent cover.

Silvertwinkie · 04-27-2007, 10:42 AM

Sounds like a great idea! Happy someone thought of it! Can't wait to see more info about it when the time comes.

Thanks RV_Cool!

dpandorf · 05-01-2007, 02:29 AM

Since I just bought a 2000 34' Limited, have found out after the fact of buying that of course my fridge is affected. Got in touch with a local RV repair center and he can get me in on May 11th. Dometic is making him buy 8 kits. He can't just buy one kit at a time.

(BTW, also not happy that when my wife went to Dometic's site that our previous owner had already contacted Dometic and registered their fridge to be repaired. Sure would have liked to have known that during the sale!)

dieterdog · 05-01-2007, 04:59 AM

Hi All, took trailer in for the recall repair,, we will wait and see what happens,, think the rv cool device is a great added safety measure,, waiting for more info on that for sure,, thanks,, donna

ZoominC6 · 05-06-2007, 06:49 AM

Quote:

Originally Posted by RV_cool

working on the instructions now, it may be until next week till I get them done. I can say you install it from the outside of the coach thru the vent cover.

I'd be interested. Please keep us posted.
Got our letter this week regarding the frig and now have to get up to the Airstream to see if ours is included in the recall. If so, finding a reliable repair service to undertake the mandated repair should be interesting. Not good timing at all going into the camping/travel season.