Dometic 2193 Fridge not cooling on propane

[xxxapache]

Sorry totally forgot to include in my last post that I did verify gas pressure. I'm hoping I did it correctly: there was a port under the fridge gas control that had a nut on it. I unscrewed the nut, put my manometer on and turned the gas on to high and it was reading just over 12 inches. I adjusted the regulator and brought it down to 11 inches.

You need to adjust it with a load on the system. Make the adjustment with the stove burning and WH on if you have one.

 

[grrrrraham]

You need to adjust it with a load on the system. Make the adjustment with the stove burning and WH on if you have one.

OK I will try again later today with a load. I have a furnace and stove, that's it. I'll turn both on. ANd just to confirm, is it OK to use the little port under the fridge control panel?

 

[xxxapache]

I can't confirm use of that port....My TT has a dial gauge manometer in the line that supplies the fridge.

 

[Wrenchgear]

OK thanks for that suggestion. Here's one more question: I assume those fins have the same purpose and effect as when on 120v? If they get enough airflow on 120v to cool adequately would it make a difference if that same airflow was also available on propane or would make sense that it would need more flow on propane?

Yes the fins have the same purpose on 120v, 12v, and propane. I only mentioned that because maybe the fridge hasn't been on long enough for it to cool down yet. You said all the tubes were hot and the top of the cabinet was hot, so I would think that all should be good to go. You also mentioned that you thought that maybe the flame might be a slight bit bigger, so that seems good. I'm just covering all the bases. Thats why I asked how cold it is now that its been running all night long.

 

[grrrrraham]

Yes the fins have the same purpose on 120v, 12v, and propane. I only mentioned that because maybe the fridge hasn't been on long enough for it to cool down yet. You said all the tubes were hot and the top of the cabinet was hot, so I would think that all should be good to go. You also mentioned that you thought that maybe the flame might be a slight bit bigger, so that seems good. I'm just covering all the bases. Thats why I asked how cold it is now that its been running all night long.

Sorry if I came across as thinking your question didn't make sense--it was more me trying to understand the operation of the fridge. Appreciate all the insight. So I turned the fridge off last night assuming it wasn't cooling well enough. How long does it take to cool down on Propane? I did not have it previously plugged into 120v yesterday so it was cooling from scratch on propane with an outside temp of about 20 degrees C.

 

[Wrenchgear]

No, not at all. You didn't come across as anything negative. My fridge always cools down faster on propane as compared to 120v. But without a cooling fan on those fins, it will take longer than what I remember. I used to always count on a full day (24 hrs) to get it cold. Should be similar, or slightly faster than what you are used to on 120v.

 

[Anthony Hitchings]

one last idea - if some idiot like me removed the internal fins for a look-see - he/she broke the thermal bond to the thermal mastic in between the back of the fins and the black ammonia tube inside the back of cooled frig space (NOT at the rear of the outside of the frig). Unless this problem was addressed correctly, the frig may never cool properly again. I still need to fix and test my frig on account of this. I just ordered a full tube or Norcold Thermal Mastic from Amazon

 

[pej]

Did you ever get your fridge working on propane? I have not been on PopupPortal for some time so I was not following. I had the same problem as you - twice. The first time I had trouble, my regulator was not putting out 11" of propane pressure and adjusting it that solved it. The second time, it was not pressure related. I borrowed a high temperature probe from work and measured the tubing at the top, just before the fins. 120v and 12v brought the temp higher than propane did (270 degF vs 245). It was only about 25degF difference, but it was enough. I took the little aluminium jet out again after cleaning it and inspected it with a high power magnifier. I discovered a curl of aluminium (like from a drill bit) across the orifice. I used a needle to break off the curl and then I broke all the rules and gently put the needle in the hole (without enough force to increase the hole size). That was all that was required to get my fridge to work great on propane. The curl was there for years before it finally blocked the hole.
This may not be your problem, but persevere, as the flame is not quite hot enough.

 

[grrrrraham]

Did you ever get your fridge working on propane? I have not been on PopupPortal for some time so I was not following. I had the same problem as you - twice. The first time I had trouble, my regulator was not putting out 11" of propane pressure and adjusting it that solved it. The second time, it was not pressure related. I borrowed a high temperature probe from work and measured the tubing at the top, just before the fins. 120v and 12v brought the temp higher than propane did (270 degF vs 245). It was only about 25degF difference, but it was enough. I took the little aluminium jet out again after cleaning it and inspected it with a high power magnifier. I discovered a curl of aluminium (like from a drill bit) across the orifice. I used a needle to break off the curl and then I broke all the rules and gently put the needle in the hole (without enough force to increase the hole size). That was all that was required to get my fridge to work great on propane. The curl was there for years before it finally blocked the hole.
This may not be your problem, but persevere, as the flame is not quite hot enough.

Thank you so much for your reply (and everyone elses). I have still not solved the issue, although I may have improved things *slightly*.

I've completely taken things apart three times now. The chimney/flue and baffle are as clean as can be--they were never dirty to begin with.

The burner jet has been soaked in alcohol and goo gone and sprayed through with high pressure air a couple times.

On one occasion I noticed lint coming out of the burner assembly (the channel that the burner jet would be pushing gas into). I sprayed this thoroughly with air as well.

Still, my fridge barely cools on propane.

The one thing that I keep coming back to is the burner jet (as you are indicating in your post as well). Mine does not come out of the burner assembly. i've tried tapping/hitting and lightly pressing and it's jammed. So I'm really not able to give the assembly or jet a good look or clean.

I think my next step is to be a bit more forceful in removing the burner jet and/or just replacing the entire assembly (it's quite rusted).

I would just like confirmation that given the following, the only remaining culprit has to be the burner jet/assembly:
- regulator is putting off 11" or water column, under system load
- chimney is clear and clean
- baffle is clean
- 120v and 12v operation is very good
- flame is blue and the heating chamber feels very hot

Thanks again to everyone!

 

[Anthony Hitchings]

Going back to basics, the frig (ammonia system) is a black box that cools, if you apply heat in the "boiler" . Your electric heat works great .

Propane looks like its working "flame is blue and the heating chamber feels very hot" yet your frig black box is not "feeling the heat" !! :-(

Does your chimney have the internal (suspended) twisted plate internal baffle (part #48) which aids in heat transfer from the hot gas to the boiler?

 

[grrrrraham]

Yep the baffle is there.... I've taken it out a couple times and cleaned it. It was already super clean to begin with. I'm fairly certain my issue lies at the jet....

 

[pej]

Thank you so much for your reply (and everyone elses). I have still not solved the issue, although I may have improved things *slightly*.

I've completely taken things apart three times now. The chimney/flue and baffle are as clean as can be--they were never dirty to begin with.

The burner jet has been soaked in alcohol and goo gone and sprayed through with high pressure air a couple times.

On one occasion I noticed lint coming out of the burner assembly (the channel that the burner jet would be pushing gas into). I sprayed this thoroughly with air as well.

Still, my fridge barely cools on propane.

The one thing that I keep coming back to is the burner jet (as you are indicating in your post as well). Mine does not come out of the burner assembly. i've tried tapping/hitting and lightly pressing and it's jammed. So I'm really not able to give the assembly or jet a good look or clean.

I think my next step is to be a bit more forceful in removing the burner jet and/or just replacing the entire assembly (it's quite rusted).

I would just like confirmation that given the following, the only remaining culprit has to be the burner jet/assembly:
- regulator is putting off 11" or water column, under system load
- chimney is clear and clean
- baffle is clean
- 120v and 12v operation is very good
- flame is blue and the heating chamber feels very hot

Thanks again to everyone!

When I unthread the propane pipe fitting from the cast iron burner the small aluminium jet is just loose and shakes out for cleaning and inspection. If yours is jambed in then it is likely bent and deformed. First purchase a new jet and then proceed to remove the old one from the burner. You'll likely destroy it since it is so thin.

I expect that this is the source of your troubles. If it does not raise the temperature of the ammonia high enough, it will not turn to gas and cool.

Keep at it. Propane is great when camping without power.

 

[grrrrraham]

When I unthread the propane pipe fitting from the cast iron burner the small aluminium jet is just loose and shakes out for cleaning and inspection. If yours is jambed in then it is likely bent and deformed. First purchase a new jet and then proceed to remove the old one from the burner. You'll likely destroy it since it is so thin.

I expect that this is the source of your troubles. If it does not raise the temperature of the ammonia high enough, it will not turn to gas and cool.

Keep at it. Propane is great when camping without power.

Awesome thanks for that. Yeah I'm pretty convinced it's the jet as well. Do you think there's any use in replacing the burner assembly while I'm at it? Mine seems rather rusted...

 

[pej]

Awesome thanks for that. Yeah I'm pretty convinced it's the jet as well. Do you think there's any use in replacing the burner assembly while I'm at it? Mine seems rather rusted...

I am not sure. As long as the fuel is getting through, it should not matter if there is rust. Decide based on price, availability, and delivery time.