What is the difference between an Air Handler, Air Conditioner, and a Heat Pump?

[Googer]

What is the difference between an Air Handler, Air Conditioner, and a Heat Pump? If I am buying/shopping for a new system, do I need all three or does just one of those do the job? What do I need to keep cool this summer and do it efficiently?


I live where it does not snow, what makes and models of HVAC units do you recommend? Trane (I've heard they are efficient) , American Standard, and Carrier have been considered, but I am somewhat clueless here.

 

[DayLaPaul]

Well I know that a heat pump works by recycling the air and slowly making the air temperature rise versus a traditional furnace type heater that blows hot air. They are supposed to be more efficient but people a lot of people like being able to warm up by sitting next to a vent.

 

[sandorski]

Originally posted by: DayLaPaul
Well I know that a heat pump works by recycling the air and slowly making the air temperature rise versus a traditional furnace type heater that blows hot air. They are supposed to be more efficient but people a lot of people like being able to warm up by sitting next to a vent.

You sure? I thought a Heat Pump circulates a liquid(Water IIRC) through pipes buried in the ground(approx 5ft under). At that depth the Temperature is always 57(ish)F, providing some Heat(still need to top off) during the Winter and cooling during the Summer.

 

[lxskllr]

Originally posted by: sandorski


You sure? I thought a Heat Pump circulates a liquid(Water IIRC) through pipes buried in the ground(approx 5ft under). At that depth the Temperature is always 57(ish)F, providing some Heat(still need to top off) during the Winter and cooling during the Summer.

Some may, but I think that's a newer design. AFAIK heat pumps just transfer energy the same way a Peltier cpu cooler does.

 

[Colt45]

A heat pump is just an air conditioner (heat exchanger) with a reverse switch on it

 

[Googer]

Originally posted by: Colt45
A heat pump is just an air conditioner (heat exchanger) with a reverse switch on it

When buying a new system, do I need both or do I pick one over the other? Does one augment the other?

 

[lxskllr]

Depends on how much you want to spend. Heatpumps suck, there's no 2 ways about it. If you're already in the 90s, I'd get a real a/c unit, and use a heatpump for your light(I assume) winter heating. This will cost more, but I think it'll be more satisfying in the long run.

 

[Googer]

Originally posted by: lxskllr
Depends on how much you want to spend. Heatpumps suck, there's no 2 ways about it. If you're already in the 90s, I'd get a real a/c unit, and use a heatpump for your light(I assume) winter heating. This will cost more, but I think it'll be more satisfying in the long run.

Cold weather is rare in these parts of the country. We've only had snow since the 1970's. I only own two jackets and three pairs of long pants.

I care about efficiency and want the most efficient and reliable system available. What should I get?

 

[lxskllr]

I'm not a HVAC guy, but a heatpump will work it's ass off for mediocre cooling in 100F weather. It'll be fine for winter heat, but I think you'd be more satisfied with a real a/c unit. You'd have to compare power consumption numbers, but I bet they're close when you take your heat level into account.

Edit:
You could use a heatpump if you want to go with a geothermal solution, but that'll be considerably more expensive to install, and it requires digging up your yard to install the pipes.

 

[Rubycon]

Air conditioner is a package unit. Air handler is a fan in a box usually with coils carrying heated water, chilled water, refrigerant, dampers for "free cooling" via outside using enthalpy controls, as well as apparatus to humidify the air. AHU and HVU (heating/ventilating unit) usually refer to commercial installations.

Heat pumps are nothing more than air conditioning units with a reversing valve that allows the coils to change places (evaporator/condenser). They're more complicated as they need timers/sensors for defrosting the outdoor coil in the winter as well as an oversized suction accumulator to protect the compressor from flooding with liquid refrigerant when operating for prolonged periods at low ambients.

 

[Googer]

Originally posted by: Rubycon
Air conditioner is a package unit. Air handler is a fan in a box usually with coils carrying heated water, chilled water, refrigerant, dampers for "free cooling" via outside using enthalpy controls, as well as apparatus to humidify the air. AHU and HVU (heating/ventilating unit) usually refer to commercial installations.

Heat pumps are nothing more than air conditioning units with a reversing valve that allows the coils to change places (evaporator/condenser). They're more complicated as they need timers/sensors for defrosting the outdoor coil in the winter as well as an oversized suction accumulator to protect the compressor from flooding with liquid refrigerant when operating for prolonged periods at low ambients.

So should I get all three?

 

[Newbian]

Don't forget that AC units often have mice popping out of them.

 

[Rubycon]

If you want to cool a single room you want an air conditioner. (window shaker)

If you want to cool your whole dwelling you want a central AC (CAC) system comprising of an outdoor unit (condenser) and indoor unit (air handler sometimes called a furnace).

If you already have forced air heating (gas for example) you can have a A coil installed above the furnace. You can also reduce the cost if gas is high by installing a heat pump with an A coil in a gas furnace and use a lockout type thermostat set at a temp usually 10-15 degrees above the balance point depending on your climate.

If you have no forced air heat (boiler/radiators/baseboard) you will need a ductless split system if you want to cool off more than a room or two. It uses an outdoor unit but instead of having an airhandler/furnace the inside unit is slim and mounts on the ceiling or wall high up and circulates the air through the conditioned space.