Regarding the back-and-forth on air conditioners, I tried Google searching to find a precedent for this sort of analysis; the first Google result was “air conditioner single vs. dual hose” was this blog post, which acknowledges the inefficiency johnswentworth points out, overall recommends dual-hose air conditioners, but still recommends single-hose air conditioners under some conditions, and claims the efficiency difference is only about 12%.
Highlights:
In general, a single-hose portable air conditioner is best suited for smaller rooms. The reason being is because if the area you want to cool is on the larger side, the unit will have to work much harder to cool the space.
So how does it work? The single-hose air conditioner yanks warm air and moisture from the room and expels it outside through the exhaust. A negative pressure is created when the air is pushed out of the room, the air needs to be replaced. In turn, any opening in the house like doors, windows, and cracks will draw outside hot air into the room to replace the missing air. The air is cooled by the unit and ejected into the room.
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Additionally, the single-hose versions are usually less expensive than their dual-hose counterparts, so if you are price sensitive, this should be considered. However, the design is much simpler and the bigger the room gets, the less efficient the device will be.
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In general, dual-hose portable air conditioners are much more effective at cooling larger spaces than the single-hose variants. For starters, dual-hose versions operate more quickly as it has a more efficient air exchange process.
This portable air conditioning unit has two hoses, one functions as an exhaust hose and the other as an intake hose that will draw outside hot air. The air is cooled and expelled into the area. This process heats the machine, to cool it down the intake hose sucks outside hot air to cool the compressor and condenser units. The exhaust hose discard warmed air outside of the house.
The only drawback is that these systems are usually more expensive, and due to having two hoses instead of one, they are slightly less portable and more difficult to set up, yet most people tend to agree the investment in the extra hose is definitely worth the extra cost.
One thing to bear in mind is that the dual hose conditioners tend to be louder than single hoses. Once again, this depends on the model you purchase and its specifications, but it’s definitely worth mulling over if you need to keep the noise down in your area.
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All portable air conditioner’s energy efficiency is measured using an EER score. The EER rating is the ratio between the useful cooling effect (measured in BTU) to electrical power (in W). It’s for this reason that it is hard to give a generalized answer to this question, but typically, portable air conditioners are less efficient than permanent window units due to their size.
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DESCRIPTION | SINGLE-HOSE | DUAL-HOSE
Price | Starts at $319.00 | Starts at $449.00
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Energy Efficient Ratio (EER) | 10 | 11.2
Power Consumption Rate | about $1 a day | Over $1 a day
EER does not account for heat infiltration issues, so this seems confused. CEER does, and that does suggest something in the 20% range, but I am pretty sure you can’t use EER to compare a single-hose and a dual-hose system.
All portable air conditioner’s energy efficiency is measured using an EER score. The EER rating is the ratio between the useful cooling effect (measured in BTU) to electrical power (in W). It’s for this reason that it is hard to give a generalized answer to this question, but typically, portable air conditioners are less efficient than permanent window units due to their size.
For example, a 14,000 BTU model that draws 1,400 watts of power on maximum settings would have an EER of 10.0 as 14,000⁄1,400 = 10.0.
A 14,000 BTU unit that draws 1200 watts of power would have an EER of 11.67 as 14,000⁄1,200 = 11.67.
Taken at face value, this looks like a good and proper metric to use for energy efficiency. The lower the power draw (watts) compared to the cooling capacity (BTUs/hr), the higher the EER. And the higher the EER, the better the energy efficiency.
Thus, if we were to look at the EER of the two example units above we could easily say that the second has better energy efficiency because it has a higher EER – 11.67 compared to 10.0.
However, taking into account what you’ve learned so far about the old method used to determine cooling capacity (standard BTUs) vs the new method used to do so (SACC), you should be able to spot one major problem with EER. That’s right. It uses standard BTU’s – yes, the old BTU metric – in its equation.
The Department of Energy also recognized this issue with EER and acted accordingly by instituting a new metric by which to determine a portable AC unit’s energy efficiency.
That metric is called CEER – Combined Energy Efficiency Ratio.
Unfortunately, CEER is a lot more complicated than EER. The new energy efficiency ratio could have simply involved taking SACC and dividing it by maximum power draw on cooling mode in watts. But the DOE decided that the equation needed a little bit more nuance than that. Let’s take a look at the end result:
EER measures performance in BTUs, which are simply measuring how much work the AC performs, without taking into account any backflow of cold air back into the AC, or infiltration issues.
Regarding the back-and-forth on air conditioners, I tried Google searching to find a precedent for this sort of analysis; the first Google result was “air conditioner single vs. dual hose” was this blog post, which acknowledges the inefficiency johnswentworth points out, overall recommends dual-hose air conditioners, but still recommends single-hose air conditioners under some conditions, and claims the efficiency difference is only about 12%.
Highlights:
EER does not account for heat infiltration issues, so this seems confused. CEER does, and that does suggest something in the 20% range, but I am pretty sure you can’t use EER to compare a single-hose and a dual-hose system.
I assumed EER did account for that based on:
This article explains the difference: https://www.consumeranalysis.com/guides/portable-ac/best-portable-air-conditioner/
EER measures performance in BTUs, which are simply measuring how much work the AC performs, without taking into account any backflow of cold air back into the AC, or infiltration issues.