Hey Everyone-I have a Dometic s1621 Gas/Electric 5.9 CF Fridge in my 1993 which is original. I bought this RV for a song last fall; It was taken care of very well up until a few years ago but then basically sat for a few years and was sold in a divorce firesale. Basically, the fridge is 2/3 of the way to being dead. The Fridge is not cold anymore whatsoever; matter of fact when I feel the fins it feels warm. Ive taken the RV on a few 3 day trips over the last month, and the lack of cold has gotten gradually worse each time.The Freezer now seems somewhat cold, but not anywhere near cold enough to freeze stuff. This past trip when we found the fridge wasn’t doing its job, we took everything and moved it to the freezer (The stuff that was already in the freezer was melted anyways). A day later at the end of the trip, the stuff is all questionable and got thrown out. I’m no maytag repairman, but it seems to me that it’s something either electronic, or has something to do with the cooling unit. Due to the age of the fridge, It is foolish to try and fix it, right? Just pull out the fridge and replacing it is the correct move here, right? Before I go and research finding another fridge, I want to make sure I haven’t missed something…..I’ve taken the RV on 3 trips over the last month, and the fridge has gotten gradually worseI’m just looking for input here to make sure I’m not missing something simple, and maybe someone can point me in the right direction to finding another one for reasonable money.Thanks in advance!

You didn't mention what MODE it was using when it no longer worked (or if it included both LP and electric mode). If it doesn't work on either mode it is PROBABLY a loss of refrigerant which is pretty much terminal. Check to be sure the gas flame is burning properly and that the electric element is getting power and it's probably safe to assume that if both of these things are working properly, it's toast. The fact that it lost it ability to cool GRADUALLY is another indication of refrigerant loss.Good luck / Skip

Ahhh yes...Mode........Well the Fridge will only run off Electricity if it is hooked up (Which it is). If I try to alternate to gas while it is plugged in, the check light comes on the fridge telling me I can only run it in Electrical mode.I never really checked to see if it runs colder on gas alone, but would it really matter if it did? If It can't cool via electric then what good is it to me?And yes, it is cleaned up, working, and getting juice...I know that for sure. The fridge was working fine for the last 6 months, but has gradually gotten worse for the last few weeks which has coincided with increased use.

If it fails only on electric then it COULD be something simple like the electric heater. Hard to say though if the LP mode never worked. The "check" light simply tells you that the gas burner did not light. It will make a set number of attempts (usually about 10 minutes worth) then go into lock out mode. Once you turn it off then back on again, it will start the lighting sequence again. If it hasn't been using LP gas for quite some time it may be difficult to light and take a number of attempts before it gets all of the air out of the lines. It is POSSIBLE that if the gas would light it may cool in LP mode. It does require heat from ONE source or the other to cool. I'd start by checking or having checked, the electric heating element. It could also be the thermostat causing the problem. The thermostat also is a 12 volt item so has a small fuse in the line (usually inside the control box) so checking that fuse would also be a good idea but usually that would go out suddenly. USUALLY when the fridge looses it's coolant you see a yellow sulfur looking powder from the ammonia loss and the smell is easily noticeable also.

take the outside fridge vent off-- look for yellow powder- which would be from the ammonia sulfur leaking. Hope and pray you don't find any-- this is the death of the fridge-- new fridge is over $1000; refurbishing the cooling system will cost $800.Could be electronic (lets hope)1. When running on electric there is a heating element which heats the sulfur ammonia. If heating element is broke then fridge won't cool2. The temp gauge which sends signal to heat up the ammonia to cool is called a 'mister' this is usually located near the fins in the fridge- if this breaks then and doesn't send the signal to cool then...warm fridge3. Igniter is electronic solenoid which lights the pilot-- but first try cleaning the pilot of cobwebs and ensure gas is getting to it. You can try to manually light the pilot. RV fridges work better on gas than electric 4. Could be the circuit board- but if check light is on then circuit appears to be working.

If I were you, I'd pay a competant RV service guy to properly diagnose and fix what's wrong, it might be a small cost fix as described above. Yellow green stains and ammonia smell means dead cooling unit. If the cooling unit is shot, it can cost around $800 and you may be successful in installing it yourself, not "a piece of cake". We had a new Norcold fridge installed for $1400. The mobile service guy had problems. The new fridge didn't cool, he installed another one, it didn't work either. He had to take fridge out, turn it upside down to get coolant into the right place and then it worked. Sometimes this turning upside down treatment will get an old cooling unit working.

Refridgerator Problems- 1993 Dometic s1621 not cold

RVNewbie1972
Explorer
May 16, 2013
Well, I found a replacement (dometic 2652) on CL. I had to travel 50 miles, but the price was right ($375), and it fit right in the spot where the old one was with cutting just an inch on the top and side.

Thanks for the help everyone!
j-d
Explorer II
May 13, 2013
We had a Dometic RM763 in our first coach, a Class C and Fridge much older than yours. I wanted to replace it with a Dometic DM2852. This called for increasing width and height of the fridge cavity but depth was OK. I measured carefully INCLUDING THE COACH DOORWAY OPENING and ordered the 2852. Tighter fit INTO the coach than measurements indicated so I had to take its doors and hinges off. For awhile I felt like the guy who built a boat he couldn't get out of his basement...
RVNewbie1972
Explorer
May 13, 2013
I found 3 on CL today......talked to a guy and am going to look at one that looks like a perfect fit tuesday afternoon. 10 year old perfect replacement with the same dimensions.......He wants $375 for it.

It took me a grand total of 40 minutes to shut off the propane, disconnect the propane and AC connections, unplug the fridge, pop off the screw covers, unscrew the 8 mounting screws, and take out the fridge......That is 2 hours TOPS total putting the new one in assuming there are any problems.....How do they get 4 hours out of it?
Holiday27
Explorer
May 12, 2013
We had a 94 and the fridge was dead when we bought it. I lucked out and the rv parts house had taken 1 from an auction and sold it to me for $350. I think it's almost not worth it to get an old one fixed. The old ones are fussy and have to be perfectly level to run right. Watch Craigslist, I see them all the time in our area. Good luck!
Bordercollie
Explorer
May 12, 2013
Those prices for diagnostics and service are probably the going rate in your area. Automotive rates are also high but RV work is a specialty like sports/luxury car or boat repair. Shop around for better price for replacement fridge if needed. It sounds as if you may not need a new cooling unit or new fridge, may only need to spend a couple of hundred bucks. We have had good service and reasonable labor charges from a local mobile RV repair guy. He works in our driveway, doesn't need brick and mortar repair shop. Meanwhile, invest in a cheap digital voltmeter/multimeter to check 12 volt DC circuits. There should be diagnostic info/advice available in the "tech issues" forum.
RVNewbie1972
Explorer
May 12, 2013
I referenced the owner's manual...The check light will automatically come on if the fridge is connected to house power; It will not allow the fridge to run off gas if electric is available. I disconnected from house power and let the fridge run off gas alone and it did (Although it still wasnt cold. I know for sure the pilot works and is firing; I cleaned it out a few months ago and can see the flame.

I dont see or smell any ammonia inside or out of the fridge

I don't have a problem with bringing the fridge somewhere to be serviced, but I need to find someone reasonable. The local place I have been using charges $110 an hour to diagnose or fix. They also gave me a price range of $1800 to $2500 to R&R the fridge if that is the case (4 hours of labor on top of either $1200 or $1800 for a new fridge)....This seems VERY pricey
Bordercollie
Explorer
May 12, 2013
If I were you, I'd pay a competant RV service guy to properly diagnose and fix what's wrong, it might be a small cost fix as described above. Yellow green stains and ammonia smell means dead cooling unit. If the cooling unit is shot, it can cost around $800 and you may be successful in installing it yourself, not "a piece of cake". We had a new Norcold fridge installed for $1400. The mobile service guy had problems. The new fridge didn't cool, he installed another one, it didn't work either. He had to take fridge out, turn it upside down to get coolant into the right place and then it worked. Sometimes this turning upside down treatment will get an old cooling unit working.
squires5
Explorer
May 12, 2013
take the outside fridge vent off-- look for yellow powder- which would be from the ammonia sulfur leaking. Hope and pray you don't find any-- this is the death of the fridge-- new fridge is over $1000; refurbishing the cooling system will cost $800.
Could be electronic (lets hope)
1. When running on electric there is a heating element which heats the sulfur ammonia. If heating element is broke then fridge won't cool
2. The temp gauge which sends signal to heat up the ammonia to cool is called a 'mister' this is usually located near the fins in the fridge- if this breaks then and doesn't send the signal to cool then...warm fridge
3. Igniter is electronic solenoid which lights the pilot-- but first try cleaning the pilot of cobwebs and ensure gas is getting to it. You can try to manually light the pilot.
RV fridges work better on gas than electric
4. Could be the circuit board- but if check light is on then circuit appears to be working.
skipnchar
Explorer
May 12, 2013
If it fails only on electric then it COULD be something simple like the electric heater. Hard to say though if the LP mode never worked. The "check" light simply tells you that the gas burner did not light. It will make a set number of attempts (usually about 10 minutes worth) then go into lock out mode. Once you turn it off then back on again, it will start the lighting sequence again. If it hasn't been using LP gas for quite some time it may be difficult to light and take a number of attempts before it gets all of the air out of the lines. It is POSSIBLE that if the gas would light it may cool in LP mode. It does require heat from ONE source or the other to cool. I'd start by checking or having checked, the electric heating element. It could also be the thermostat causing the problem. The thermostat also is a 12 volt item so has a small fuse in the line (usually inside the control box) so checking that fuse would also be a good idea but usually that would go out suddenly. USUALLY when the fridge looses it's coolant you see a yellow sulfur looking powder from the ammonia loss and the smell is easily noticeable also.
RVNewbie1972
Explorer
May 12, 2013
Ahhh yes...Mode........Well the Fridge will only run off Electricity if it is hooked up (Which it is). If I try to alternate to gas while it is plugged in, the check light comes on the fridge telling me I can only run it in Electrical mode.

I never really checked to see if it runs colder on gas alone, but would it really matter if it did? If It can't cool via electric then what good is it to me?

And yes, it is cleaned up, working, and getting juice...I know that for sure. The fridge was working fine for the last 6 months, but has gradually gotten worse for the last few weeks which has coincided with increased use.