[steppinthrax]

Two components are coming up in my reading.

1. Accumulator: I understand this (between the evaporator and compressor, there to prevent liquid from entering the compressor.
2. Receiver: I have no idea what this is for other than to hold liquid refrigerant after it's left the condenser?

 

[bustawrench1]

It's a wide spot in the road to store excess refrigerant charge until it's needed.

 

[jpsmith1cm]

Two components are coming up in my reading.

1. Accumulator: I understand this (between the evaporator and compressor, there to prevent liquid from entering the compressor.
2. Receiver: I have no idea what this is for other than to hold liquid refrigerant after it's left the condenser?

I like to think of the receiver as a holding tank.

There are times during operation that a system will require more refrigerant to be in circulation. Low ambients are the most common time.

During low ambient, the condenser is filled with more liquid. That liquid still has to be in the system during the summer, so we add a holding tank to keep it.

When a system pumps down, we also need somewhere to put the refrigerant. Again, we install a holding tank.


We call this holding tank a receiver.

 

[eric1589]

It holds excess liquid that would otherwise back up in the condenser coil an essentially reduce the size of the condenser coil.

With a reciever, the system can have liquid refrigerant back up there instead of reducing performance and efficiency by negating condenser coil size.

It's for lower load conditions when you don't need to move as much refrigerant but your system runs full capacity.

 

[steppinthrax]

That's kind of what I was thinking.

Thanks

I just thought that was too simple of a purpose.

So what your saying is if you OVERCHARGE a system the overcharge portions will end up in both the reciever and accumulator? It seems there is a "holding tank" between the evaporator and compressor and there is another between the condenser and evaporator.

So if there is too much on each side(h/l) it will end up in the receiver.

 

[jpsmith1cm]

That's kind of what I was thinking.

Thanks

I just thought that was too simple of a purpose.

So what your saying is if you OVERCHARGE a system the overcharge portions will end up in both the reciever and accumulator? It seems there is a "holding tank" between the evaporator and compressor and there is another between the condenser and evaporator.

So if there is too much on each side(h/l) it will end up in the receiver.

NO.

You are NOT overcharging the system.

You are charging it to operate properly under all possible conditions.

That refrigerant is required at some point in the operation of that system, therefore it can't be classified as an OVERcharge.

I suppose if you want to get technical, it is overcharged under certain conditions, but unless you want to come back every time the weather changes by more than about 5 or 10 degrees, you better have that gas in there...

 

[VTP99]

If your talking really over charging, like to the point that the receiver can't hold it all. That would spill over into the condenser not the evaporator.

 

[bustawrench1]

No, not over charging.

More refrigerant is required during low ambient operation in many systems, which use a head master setup to back liquid up into the condenser. This reduces the amount of coil available for heat transfer, effectively making the coil smaller and raises head pressure.

In the summer, this would make the system trip out on high head pressure, so the headmaster setup (there are a few different setups to do this) switches from stacking refrigerant in the condenser coil to storing it in the receiver.

There are also some systems around which hold more refrigerant than can be stored in the condenser coil. These systems may have a receiver for the sole purpose of storing the refrigerant during a pump down cycle.

 

[HyperFusionHVAC]

I’m sorry I’m new to this site. I’ve been in the trade doing residential service work and installs and am now getting my feet wet with refrigeration work. I want to learn as much as possible before I really start taking on too much more commercial refrigeration work but when you all say during a pump down cycle what exactly are you referring to? The only pump down I know of is when I pump a residential system down into the condenser to Open the system up and do a repair but it seems like you all are referring to something different.

 

[VTP99]

In refrigeration we use a electrically operated liquid line solenoid valve. It does the same thing you do manually to pump down a system. Instead of the condenser ( typically) the refrigerant is stored in a receiver. The valve is controlled ( typically) by a temperature control. When the valve closes and the system pumps down a low pressure control shuts down the compressor.
You should start your own thread in the future. This helps eliminate confusion between to different conversations within the same thread.

 

[HyperFusionHVAC]

Gotcha thanks, I will do that

 

[timebuilder]

Not only is it a good idea to start your own thread, but it's also a good idea to get 15 substantive posts and apply for pro membership to this site... which is free... and allows the best parts of the site... including the educational forums...to be available for your use.

 

[Falke]

... It seems there is a "holding tank" between the evaporator and compressor ....

Colleagues already explained the purpose of the "holding tank" aka. liquid receiver between the condenser and TXV (mechanical or electronic).

But, the other one, between the evaporator and compressor, is not the receiver or anything like that. Its purpose is to make sure that any liquid drops of refrigerant (not evaporated) accidentally coming from the evaporator is evaporated before it reaches the compressor. It is usually called "liqiud separator" or "suction heat exchanger". Sometimes it can have liquid line connected which provides some additional heat for evaporation and additional subcooling of liquid before the TXV.

 

[steppinthrax]

Man it's been years since I've made this post. I actually thought that the receiver was used to hold an extra charge. LOLOLOL.

As others have said, during low ambient temp the refrigerant exists more as a liquid and the receiver holds this.