SJ-Chris
Nov 12, 2022Explorer II
absorption refrigerator out of level, boiler temp control
Safety is important!
Consider a scenario where someone parks for the night (or for several days) on a steep driveway or side of the road on a hill and they are very unlevel. Assume they have their absorption refrigerator on. Without some form of temperature protection (ie. Fridge Defend, or DIY thermostat solution) this seems like it could be a dangerous situation (fridge damage and/or fire). I sometimes let others use my RVs. I tell them the refrigerator needs to be level, but most non-RVers don't really understand the importance, or they don't care because the RV isn't theirs.
I have seen from multiple posts and websites, that under "normal" operation of a "level" absorption refrigerator the boiler temperature will be ~180-190*C with either propane or plugged in.
I understand that when your refrigerator is out of level by too much (more than 3% refrigerator side-to-side or 6% refrigerator front-to-back) then the gravity functionality of some of the internal liquids in your cooling unit can stop flowing where they are supposed to flow. This can cause (blockage?) the boiler temperature to increase. Once it gets "too hot" (...I've seen on Fridge Defend's video that value is around 225*C) boiling can happen and damage can occur.
Q1: Is it accurate to say that as long as the boiler temperature is kept under some value (220*C? 210*C? 205*C?) your cooling unit will not get damaged/corroded and it will unlikely cause a refrigerator fire?
Q2: If your refrigerator is out of level (more than 3% / 6%) and continues to run, but a thermostat (or Fridge Defend) keeps the boiler from going over say 210*C, what will happen? Imagine a thermostat that cuts off refrigerator power at 210*C but then turns the refrigerator back on at 170*C and the boiler temp floats back and forth between 170*C and 210*C but the refrigerator is well out of level. What will happen? Does cooling stop because the liquids cannot flow where they need to flow? Does pressure in the system keep the fluids flowing even if off level? Does the internal temperatures of the interior of the freezer/refrigerator climb to ambient outside temperatures?
Q3: Does anyone have any examples of when their boiler got up to 300*C, 400*C, etc. Can it get that hot under some strange scenarios?
What I'm planning on doing is a DIY modification where a high temp thermostat will turn off the refrigerator once the boiler temp hits some value (ie. 210*C) and then turn it back on once it drops back down to 170*C. This will act as a high temperature protector on the boiler. Under normal operation, the boiler temp will likely not get over 190*C so things will work as they should. In the event that the refrigerator gets unlevel (or some other problem) and the temps start climbing, the thermostat will shut it off before it gets dangerous. Does anyone see anything wrong with simply cutting off refrigerator power if it hits 210*C and then restoring power once it has cooled back down to 170*C? Seems reasonable to me. Just want to check to see if I'm missing anything.
For safety reasons, I think most people with an absorption refrigerator should have something to cut off an overheating boiler situation (either a Fridge Defend or DIY thermostat) to reduce the risk of damaging their cooling unit and/or starting a fire (worst case scenario). Maybe the risk is small(?), but my DIY fix will likely only cost me $25 and an hour of time.
Thoughts?
Chris
Consider a scenario where someone parks for the night (or for several days) on a steep driveway or side of the road on a hill and they are very unlevel. Assume they have their absorption refrigerator on. Without some form of temperature protection (ie. Fridge Defend, or DIY thermostat solution) this seems like it could be a dangerous situation (fridge damage and/or fire). I sometimes let others use my RVs. I tell them the refrigerator needs to be level, but most non-RVers don't really understand the importance, or they don't care because the RV isn't theirs.
I have seen from multiple posts and websites, that under "normal" operation of a "level" absorption refrigerator the boiler temperature will be ~180-190*C with either propane or plugged in.
I understand that when your refrigerator is out of level by too much (more than 3% refrigerator side-to-side or 6% refrigerator front-to-back) then the gravity functionality of some of the internal liquids in your cooling unit can stop flowing where they are supposed to flow. This can cause (blockage?) the boiler temperature to increase. Once it gets "too hot" (...I've seen on Fridge Defend's video that value is around 225*C) boiling can happen and damage can occur.
Q1: Is it accurate to say that as long as the boiler temperature is kept under some value (220*C? 210*C? 205*C?) your cooling unit will not get damaged/corroded and it will unlikely cause a refrigerator fire?
Q2: If your refrigerator is out of level (more than 3% / 6%) and continues to run, but a thermostat (or Fridge Defend) keeps the boiler from going over say 210*C, what will happen? Imagine a thermostat that cuts off refrigerator power at 210*C but then turns the refrigerator back on at 170*C and the boiler temp floats back and forth between 170*C and 210*C but the refrigerator is well out of level. What will happen? Does cooling stop because the liquids cannot flow where they need to flow? Does pressure in the system keep the fluids flowing even if off level? Does the internal temperatures of the interior of the freezer/refrigerator climb to ambient outside temperatures?
Q3: Does anyone have any examples of when their boiler got up to 300*C, 400*C, etc. Can it get that hot under some strange scenarios?
What I'm planning on doing is a DIY modification where a high temp thermostat will turn off the refrigerator once the boiler temp hits some value (ie. 210*C) and then turn it back on once it drops back down to 170*C. This will act as a high temperature protector on the boiler. Under normal operation, the boiler temp will likely not get over 190*C so things will work as they should. In the event that the refrigerator gets unlevel (or some other problem) and the temps start climbing, the thermostat will shut it off before it gets dangerous. Does anyone see anything wrong with simply cutting off refrigerator power if it hits 210*C and then restoring power once it has cooled back down to 170*C? Seems reasonable to me. Just want to check to see if I'm missing anything.
For safety reasons, I think most people with an absorption refrigerator should have something to cut off an overheating boiler situation (either a Fridge Defend or DIY thermostat) to reduce the risk of damaging their cooling unit and/or starting a fire (worst case scenario). Maybe the risk is small(?), but my DIY fix will likely only cost me $25 and an hour of time.
Thoughts?
Chris