New Fridge Topic: A Different Approach

[escape artist]

Originally Posted by Klem

Well Parker you have me over the barrel... So to speak. We won't see 85 degrees unless the house is on fire!

Going south in February so we'll see then ... But hopefully there will be an x20 cooling unit hanging on back of this 6.7

Mel

Hi: Klem... WOW!!! I can't even smuggle a 1/4 of a red pepper into the States. How you gonna get an X20 in there? Alf
escape artist N.S. of Lake Erie

[Klem]

Originally Posted by escape artist

Hi: Klem... WOW!!! I can't even smuggle a 1/4 of a red pepper into the States. How you gonna get an X20 in there? Alf
escape artist N.S. of Lake Erie

X20 has no seeds..... Never has and never will.

Isn't that the state of affairs ... Busted Smuggling a refrigerator engine into the States ...because I don't want my dairy products not to perish.

A hero among RVers.. : ). ??

[Parker]

That should be worth at least a campfire story; maybe even a song!

[escape artist]

Originally Posted by Klem

Well Parker you have me over the barrel... So to speak. We won't see 85 degrees unless the house is on fire!

Going south in February so we'll see then ... But hopefully there will be an x20 cooling unit hanging on back of this 6.7

Mel

Hi: Klem... At 10:30 pm., the refer is down to -5*C. on Max. That's the coldest it's ever been!!! Changed the setting to 3 bars for over nite. Might just leave the thermistor where its at. Might have to start packing the salad stuff in an insulated bag again. Alf p.s. The red pepper was washed and seeded!!!
escape artist N.S. of Lake Erie

[Klem]

Originally Posted by escape artist

Hi: Klem... At 10:30 pm., the refer is down to -5*C. on Max. That's the coldest it's ever been!!! Changed the setting to 3 bars for over nite. Might just leave the thermistor where its at. Might have to start packing the salad stuff in an insulated bag again. Alf
escape artist N.S. of Lake Erie

'That's cool' Alf! Speaking from experience you may have gone too far, I did.

Listen to the burner and see if it ever turns off. I moved mine away until it 'decoupled' (the frig geek said), meaning the burner was running continuously. So then I hung the thermistor on the drain chute and got a steady 1 power setting gain. And the burner cycles on and off over a period of time.

The burner needs a rest or the system doesn't complete the normal cycle, but it seemed to me there was more cooling potential available.

Chiil out Alf : )

Mel K

[escape artist]

Originally Posted by Klem

'That's cool' Alf! Speaking from experience you may have gone too far, I did.

Listen to the burner and see if it ever turns off. I moved mine away until it 'decoupled' (the frig geek said), meaning the burner was running continuously. So then I hung the thermistor on the drain chute and got a steady 1 power setting gain. And the burner cycles on and off over a period of time.

The burner needs a rest or the system doesn't complete the normal cycle, but it seemed to me there was more cooling potential available.

Chiil out Alf : )

Mel K

Hi: Klem... Before I set it to 3 bars it ran on 2 for a while and warmed up to 0*C. If it's warming up that should indicate it's not running continuously... I'd think. More fine tuning in the am. Alf
escape artist N.S. of Lake Erie

[grc]

Concerning the RM8555, I found a Dometic web page that has their Refrigerator Recall List but it does not give a reason why the RM8555 model with the Automatic Energy Selection is on the recall list.

Has someone else already seen this and talked about this or is RM8555 being on the recall list something new?

Search - Dometic

[grc]

Here is a quote from a Dometic Service Manual for the new 8 series, RM8xxx.
This manual looks to be from 2007-10 as shown on page 1 of the pdf file, so this could be before Climate Class was started.

The quote below using the word "identical" is from page 19 of the pdf file of this Dometic manual.

"On the back side of the 8-series fridges the same components are used as with the 7xxx-Generation. Cooling unit, Gas Valve GV 100, burner control device P810, burner and heating elements are identical."

http://web.adria.dk/wp-content/uploa...ice-RM8XXX.pdf

[escape artist]

Hi: Klem et all... This am on 3 bars, the thermistor on the wire shelf, the refer is at +4*C. Perfecto!!! Wish I could create an 85*F. day to go along with my experiment. Sigh!!! Alf
escape artist N.S. of Lake Erie

[cpaharley2008]

Reading all these attachments and references to Dometic and it's subsidiaries to find the correct information reminds me a lot of doing this while I was employed and working. This is the type of stuff I had to look for and hunt for in trying to follow the money, now we are trying to follow Dometic's refer build specifics.....I need a day off

[hotfishtacos]

Originally Posted by grc

Here is a quote from a Dometic Service Manual for the new 8 series, RM8xxx.
This manual looks to be from 2007-10 as shown on page 1 of the pdf file, so this could be before Climate Class was started.

The quote below using the word "identical" is from page 19 of the pdf file of this Dometic manual.

"On the back side of the 8-series fridges the same components are used as with the 7xxx-Generation. Cooling unit, Gas Valve GV 100, burner control device P810, burner and heating elements are identical."

http://web.adria.dk/wp-content/uploa...ice-RM8XXX.pdf

Great info in the manual! Thanks!

[Klem]

Originally Posted by escape artist

Hi: Klem... Before I set it to 3 bars it ran on 2 for a while and warmed up to 0*C. If it's warming up that should indicate it's not running continuously... I'd think. More fine tuning in the am. Alf
escape artist N.S. of Lake Erie

Put an ear by the lower refer vent and you should hear the burner when it's 'on'. And/or open the vent and you'll see a flame peep hole.

Careful ... you don't want to burn up the burner

[Klem]

Originally Posted by cpaharley2008

Reading all these attachments and references to Dometic and it's subsidiaries to find the correct information reminds me a lot of doing this while I was employed and working. This is the type of stuff I had to look for and hunt for in trying to follow the money, now we are trying to follow Dometic's refer build specifics.....I need a day off

Just when you wanted a day off ... here is a 'fun' research project.

In my words - can you please check and report back in your 'spare time'?
I read the recall and it appears that in 1996ish they raised the power on the burner. By 2005ish they acknowledged that there were some fires in refrigeration units from 'unknown' source(s).They 1st said the source was burning insulation added by installers.
They hired independent research that found the burners on some units had cracked and the leaking refrigerant had ignited. They acknowledged that is was fire hazard and initiated the recall to install a protector on the burner units identified as having the problem.

?? Could this be the reason that our refrigerators are wimpy compared to the ones we had in the past? It would make sense that they lowered the burner heat and/or raised the thickness of metals to make sure there was no more fire issues?? That would result in decreased cooling performance.

It seems we can tweak small gains out the 6.7 by moving the thermistor etc. but are we moving the heat in the burner up into the danger zone they may be trying to avoid

Mel

[escape artist]

Originally Posted by cpaharley2008

Reading all these attachments and references to Dometic and it's subsidiaries to find the correct information reminds me a lot of doing this while I was employed and working. This is the type of stuff I had to look for and hunt for in trying to follow the money, now we are trying to follow Dometic's refer build specifics.....I need a day off

Hi: cpaharley2008... Kinda like a "Forensic audit"... Just as long as we're not flogging a "Dead fridge". The performance is much colder and not on max at all times. Now I need to check if the 120V. heater is cycling on/off properly. I am hopeful. Alf
escape artist N.S. of Lake Erie

[hotfishtacos]

Originally Posted by Klem

Just when you wanted a day off ... here is a 'fun' research project.

In my words - can you please check and report back in your 'spare time'?
I read the recall and it appears that in 1996ish they raised the power on the burner. By 2005ish they acknowledged that there were some fires in refrigeration units from 'unknown' source(s).They 1st said the source was burning insulation added by installers.
They hired independent research that found the burners on some units had cracked and the leaking refrigerant had ignited. They acknowledged that is was fire hazard and initiated the recall to install a protector on the burner units identified as having the problem.

?? Could this be the reason that our refrigerators are wimpy compared to the ones we had in the past? It would make sense that they lowered the burner heat and/or raised the thickness of metals to make sure there was no more fire issues?? That would result in decreased cooling performance.

It seems we can tweak small gains out the 6.7 by moving the thermistor etc. but are we moving the heat in the burner up into the danger zone they may be trying to avoid

Mel

Mel, I don't believe so. The "wimpy" performance is also seen on AC. I believe a big part of the performance issue is related to poor insulation.

[Klem]

Originally Posted by hotfishtacos

Mel, I don't believe so. The "wimpy" performance is also seen on AC.

Woodalls Open Roads Forum: Dometic Refer Recall - Possible Fire Hazard -Update 2/13/07

In April of 1997 Dometic modified the design of the affected refrigerators by increasing the wattage of the heating element from 325 watts to 354 watts. All production of the affected units from April 1997 through May of 2003 utilized the 354 watt heating element. In May of 2003, in order to improve the operating life of the refrigerators, Dometic returned to the use of the 325 watt heating element which it continues to use today. It is now believed that the use of the higher wattage heater contributed to abnormal fatigue in the boiler tube.

[rbryan4]

Originally Posted by hotfishtacos

Mel, I don't believe so. The "wimpy" performance is also seen on AC. I believe a big part of the performance issue is related to poor insulation.

I agree with Steve.

The performance is 'wimpy', but the fridge is SN climate rated, and is designed to use less energy. It's even one of the bullet points on the fridge features on their website. It uses less AC than fridges with a climate class for hot climates.

At the end of the day we're still talking about making an SN class fridge perform like a T or ST. Good luck with that.

[hotfishtacos]

The root cause of the cooling issue is complex and debatable but I'm sure we all agree that they are, "wimpy", the best descriptive term I've heard so far!
..

[Brian B-P]

Originally Posted by Klem

The burner needs a rest or the system doesn't complete the normal cycle...

I don't get that - the absorption refrigeration cycle is continuous, not a batch process, right?

[rbryan4]

Originally Posted by Brian B-P

I don't get that - the absorption refrigeration cycle is continuous, not a batch process, right?

Good point. There are basically two types - continuous cycle and intermittent cycle. Not sure which one the Dometic is. Here's a pretty good explanation of the differences:

SMALL AMMONIA REFRIGERATOR