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smart65

Propane now used in latest freezers

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We just bought a new Frigidaire chest freezer. I was interested to read in the user manual that the refrigerant it contains is flammable. I assume it is a propane based product like Duracool or Canadian Tire's REDTEK. I wonder how long it will take for this product to be recognized by the authorities as safe for use in automobiles. Currently, the product can be purchased, but I'm pretty sure that no licensed air conditioning specialist can legally install it. I had CsC member Bessy install it in my car last summer. Advantages: it is non-ozone depleting and, due to the larger molecule size, doesn't leak as easily as conventional refrigerant.

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A friend who grew up in England said he can remember ammonia being used, but he thought that it was discouraged because of its toxicity.

Edited by smart65

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I have had fridges for the last 20 years and they all run on propane , love it , they are quiet and the freezer section does a great job making ice cream rock hard the way I like it.

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When you say they run on propane do you mean they burn propane as a fuel? RV refrigerators use electricity or propane as a fuel to heat the refrigerant. Sounds counterintuitive to use heat to cool. But that is how these ammonia based systems work.

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When you say they run on propane do you mean they burn propane as a fuel? RV refrigerators use electricity or propane as a fuel to heat the refrigerant. Sounds counterintuitive to use heat to cool. But that is how these ammonia based systems work.

You got there first. Yep. Propane fridges burn propane to create heat to initiate the absorption process in AMMONIA fridges. Propane is a heat source, not a coolant. They can also use an electric element to generate the heat needed to cause this effect. They are generally quite inefficient in comparison to electric compressor models...eg...residential types.

Note. In large motorhomes and fithwheels propane two way fridges are starting to get a little rare and many manufacturers are opting for the residential compressor models.

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Yup, it is what many LNG plants use to cool the natural gas to the condensation point. The propane is extracted from the natural gas, easy, simple system.

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Yes, propane and ammonia can be used in both vapour-compression and absorption systems. Ammonia cannot be used as a fuel (heat source) in absorption systems.

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They are generally quite inefficient in comparison to electric compressor models...eg...residential types.

It depends on what you mean by efficient. Compressor models are far more effective at cooling compared to the weaker cooling system in an absorption refrigerator. However where the cost of the energy source comparison is between natural gas (or propane) used in the absorption system and electricity used in the compressor systems, the absorption refrigerator can be cheaper to operate.

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For RV's and locations without any mains electricity supply, an absorption fridge powered by propane gas or kerosene is the only option.

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They are generally quite inefficient in comparison to electric compressor models...eg...residential types.

It depends on what you mean by efficient. Compressor models are far more effective at cooling compared to the weaker cooling system in an absorption refrigerator. However where the cost of the energy source comparison is between natural gas (or propane) used in the absorption system and electricity used in the compressor systems, the absorption refrigerator can be cheaper to operate.

People often confuse efficiency with cost of operation.

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I do own a recent Frigidaire conventional refrigerator (Freezer compartment at the top).

When their licenced technician came over last week to change a door gasket that was prematurely coming off (under warranty repair) , I asked the guy why the compressor was louder than one should expect from a new appliance (rather loud, unpleasant, metallic kind of buzz). Among other considerations such as cheaper condenser design, I was told that due to the new refrigerants now used in domestic fridges, the compressor has to work harder, increasing noise levels as a consequence.The technician mentionned R134a refrigerant now used as the industry standard (I first confused this with the actual R234 used in our smart A/C system).

Inorder to reduce the noise, this technician wrapped some foam tape around the line that connects the compressor to the freezer evaporator. This fix was unsatisfactory, and I guess that the tradeoff for an allegedly more efficient, environment-friendy fridge is to cope with some increased noise,unless I decide to work wonders with mineral wool one fine day :scratch:

Edited by Da Shoumi

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They are generally quite inefficient in comparison to electric compressor models...eg...residential types.

It depends on what you mean by efficient. Compressor models are far more effective at cooling compared to the weaker cooling system in an absorption refrigerator. However where the cost of the energy source comparison is between natural gas (or propane) used in the absorption system and electricity used in the compressor systems, the absorption refrigerator can be cheaper to operate.

I get that but I was specifically speaking about the RV fridge absorption style. A typical 12 cubic foot absorption model when in electric mode uses a 4 amp element to heat the boiler in an absorption fridge. The duty cycle is about 60 to 80 percent on a 30 degree celcius day. A 22 cubic foot residential compressor model uses about 1.1 to 1.4 amps of power with about a 30 to 40 percent duty cycle. (ours is on the lower end of this scale) So in terms of power used the residential compressor model is more efficient.

Many of those who didn't get a residential fridge in their rig from the factory choose to upgrade when their Absorption model fails. Because of the wasted space taken up by the cooling unit in the absorption model, when people switch to the residential they find they are able to put a 22 cubic foot residential in. Kinda cool.

Hope that helps.

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For RV's and locations without any mains electricity supply, an absorption fridge powered by propane gas or kerosene is the only option.

Good morning. Certainly the majority if not all medium to high end A class motorhomes come standard with residential compressor fridges. Whirlpool, frigidaire etc. Modern fridges don't use a lot of power. between 1 to 1.5 amps and with very low duty cycles. We dry camp off the grid for weeks at a time with no difficulty. Keep in mind that these same motorhomes usually have 4 to 8 six volt batteries and robust solar systems. If we don't have sun for more than a day or two in a row the generator comes on. Many rigs now are all electric with n propane systems on board. Heat and hot water comes from diesel. Everything else is electric.

On edit. I tried to find a couple good pictures of ours and came up with these. This is a typical install.

IMG_3071.jpg

IMG_3076.jpg

Edited by John & Angela

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They are generally quite inefficient in comparison to electric compressor models...eg...residential types.

It depends on what you mean by efficient. Compressor models are far more effective at cooling compared to the weaker cooling system in an absorption refrigerator. However where the cost of the energy source comparison is between natural gas (or propane) used in the absorption system and electricity used in the compressor systems, the absorption refrigerator can be cheaper to operate.

I get that but I was specifically speaking about the RV fridge absorption style. A typical 12 cubic foot absorption model when in electric mode uses a 4 amp element to heat the boiler in an absorption fridge. The duty cycle is about 60 to 80 percent on a 30 degree celcius day. A 22 cubic foot residential compressor model uses about 1.1 to 1.4 amps of power with about a 30 to 40 percent duty cycle. (ours is on the lower end of this scale) So in terms of power used the residential compressor model is more efficient.

Many of those who didn't get a residential fridge in their rig from the factory choose to upgrade when their Absorption model fails. Because of the wasted space taken up by the cooling unit in the absorption model, when people switch to the residential they find they are able to put a 22 cubic foot residential in. Kinda cool.

Hope that helps.

Just curious, are the RV absorption models running on 120v?

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They are generally quite inefficient in comparison to electric compressor models...eg...residential types.

It depends on what you mean by efficient. Compressor models are far more effective at cooling compared to the weaker cooling system in an absorption refrigerator. However where the cost of the energy source comparison is between natural gas (or propane) used in the absorption system and electricity used in the compressor systems, the absorption refrigerator can be cheaper to operate.

I get that but I was specifically speaking about the RV fridge absorption style. A typical 12 cubic foot absorption model when in electric mode uses a 4 amp element to heat the boiler in an absorption fridge. The duty cycle is about 60 to 80 percent on a 30 degree celcius day. A 22 cubic foot residential compressor model uses about 1.1 to 1.4 amps of power with about a 30 to 40 percent duty cycle. (ours is on the lower end of this scale) So in terms of power used the residential compressor model is more efficient.

Many of those who didn't get a residential fridge in their rig from the factory choose to upgrade when their Absorption model fails. Because of the wasted space taken up by the cooling unit in the absorption model, when people switch to the residential they find they are able to put a 22 cubic foot residential in. Kinda cool.

Hope that helps.

Just curious, are the RV absorption models running on 120v?

Yes and no. The small 4 cubic foot and smaller type absorption you find in a truck camper or pop up for example are called "three way" fridges that work on 12, 120 and propane. Anything bigger than about 5 feet are 120 volt and propane only. The electric element as the heat source sucks too much out of the battery.

Hope that helps.

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Good morning. I'm not up on kerosene fridges that much. I always thought they were just an absorption fridge that used kerosene as a heat source instead of propane, electricity or natural gas. Are you saying there are kerosene fridges that use kerosene as a coolant? Never heard of that.

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Good morning. I'm not up on kerosene fridges that much. I always thought they were just an absorption fridge that used kerosene as a heat source instead of propane, electricity or natural gas. Are you saying there are kerosene fridges that use kerosene as a coolant? Never heard of that.

Not trying to sound like a pedant, and I think everyone actually understands here, but just for clarity purposes, the proper term would be refrigerant.

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Good morning. I'm not up on kerosene fridges that much. I always thought they were just an absorption fridge that used kerosene as a heat source instead of propane, electricity or natural gas. Are you saying there are kerosene fridges that use kerosene as a coolant? Never heard of that.

Not trying to sound like a pedant, and I think everyone actually understands here, but just for clarity purposes, the proper term would be refrigerant.

That is correct. My bad. Did a quick search though and couldn't find anything referring to kerosene as a refrigerant. I think the other poster is referring to an ordinary absorption fridge that uses kerosene as a heat source. Common in the cottage world.

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