Evaporator coils are not always indoors

According to this practice question, evaporator coils on a split system are always located indoors. But this is not true up here in Canada where we might use a split system for heating. Or is it?

Practice Questions - InterNACHI®

With split systems, the condenser unit is typically outdoors and the evaporator indoors.

The only exception I have see to this rule is a package unit, which is typically reserved for commercial use but I have seen them in residential.

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When running in heat mode the evaporator is outside and the condenser is indoors (reverse is true in cool mode - key word being reverse which is why heat pumps have a “reversing valve”). By design, the indoor and outdoor units for a heat pump change (reverse) functions.

The best way to identify equipment is just, “indoor unit” or “outdoor unit” to avoid confusion as to what you are talking about.


Agreed, when speaking of heat-pumps.

Morning, David.
Hope you are in good spirits today.

That is not the way I understand how the question is being posed.
T/F: True or False. The evaporator coil in a slit system is located outdoors. Answer: False.
Why? The evaporator coil in a split system is located indoors. An evaporator coil is the part of an HVAC system ‘that absorbs heat’ from the air in a residence.

The warmer refrigerant circulates through the line set to the condenser coil (outside), where the heat is deposited into the surrounding air.

When it comes to Heat Pumps, it is best not to even call a coil evaporator/condenser.


Now that is very confusing, Robert. I know what you mean, but no one else will.

The refrigerant returning to the condenser is in the cold suction line. The warm line is on its way to the metering device at the evaporator.

The compressor makes the cold refrigerant HOT before it goes to the condenser.

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I don’t understand, you are correct. The answer is false.

What people are reading into this; A Heat Pump has the Evaporator (Incorrect terminology) outdoors in the heat mode.

As posted; do not call HP Coils Evap/Cond. They are working as an evap coil, for the moment. Until it goes into defrost. Use Indoor/Outdoor.

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Yes, that’s what I thought. That’s why this question seems off to me. Especially up north here in Canada.

This would only make sense of the question specified that it was an air conditioner. But there was no such clarification so we cannot make that assumption. It must also apply to a split heating system which is reversed.

Again, this assumes the split system is for air conditioning, and only air conditioning. I don’t think we can make that assumption.

Yes, you can.

If you call your HVAC Guy and tell him you have a Heat Pump and start talking about evp/cond coils he will probably say “I thought you were talking about a Heat Pump?”. It is an Industry Standard, just like HI’s have standards to call things. Do you have a foundation “Footer” or a “Footing”? Some people seem to care.

At any rate, who cares? It’s just a NACHI Quiz.

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Morning, David.
As always, hope this post find you well and in good spirits.

David, you only used half my post quote. The full post reads as follows: “The warmer refrigerant circulates ‘through the line set’ to the condenser coil (outside) , where the heat is deposited into the surrounding air.” Emboldened is the consideration.

As well consider, the evaporator coil, in a HVAC system, Heating, Ventilation and Air Conditioning, is the part of the HVAC, Air Conditioners’ or Heat Pumps system that absorbs heat from the circulated air that is forced by it.

The questions just says “split” which often employs heat pumps so you have to assume heat pumps, which would make this answer wrong.

This is only true if the split system is used for air conditioning, but not true if it’s used for heating. I thought you were based in Canada? I’ve never inspected a split system so it’s possible I’m confused about something but that’s why I posted this question. It just seems strange to me that the correct answer assumes air conditioning when it could be a heat system which would make this answer wrong.

The reason I care, and the reason I posted this question, is because studying, even memorizing this NACHI quiz is my best chance at passing the Albert licence exam.

Don’t box yourself in or ass/u/me. It leads down slippery slopes. IE: Mini Split.

We are generalist and in general terms it is common to describe a system in the following manner to a laymen or homeowner.

“With a heat-pump the process reverses in the winter and the evaporator coil expels heat from the refrigerant into your home instead of absorbing it and taking it outdoors. Most heat pumps have auxiliary heating elements that are part of the evaporator coil components to supply heat when temperatures fall below a certain point.”

And I do not disagree with anything @dandersen has said. Indoor/outdoor always works best for heat-pumps. But I can guarantee you for the purpose of this quiz, evaporator inside is the correct answer.

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I don’t think that trope applies in this case. The question expects an assumption which doesn’t apply in Canada. The question clearly states that it is WRONG to think the evaporator coil in a split system would be located outside. But it’s not wrong to think that, or is it? Am I wrong? I don’t think so. It’s only wrong if you assume a hot southern climate, which I would never assume in Canada and there is no constraints in the question that would lead me to assume a hot southern climate. So, is it just because I’m such a noob that I don’t know or understand the industry? Does the industry always speak of evaporator coils as indoor even though they are not indoors in a warming system?