Anti Short Cycle

[schow168]

Dear all,

I am new in the air conditioning field and have some questions about the 'anti short cycle' of an air conditioner's compressor.

Please can anyone tell me what exactly is 'anti short cycle' of an air conditioner's compressor? Why do we need 'anti short cycle'?

If my air conditioners' compressors are started with 1-phase and 3-phase soft starters, does 'anti short cycle' still required?

If yes, what would be the most optimum time for 'anti short cycle'?

Many thanks!

[Tesla]

Hi schow168 and welcome to the forum.
In short the anti recycle timer prevents the compressor from starting for a period of time after it stoped last. Yes it is still required with soft starters. If the unit developes a fault such as short of gas (with lp auto reset) you would find out sooner with unsatisfied conditions. Also even very big soft starters heat up a lot more durring start up. If the unit was SOG and relied on suction cooling for the windings could over heat.

[schow168]

Hi Tesla,

Thanks for your advice!

So are the anti short cycle periods same for all air cond manufacturers? If not how and where can I find out how long should this period be?

Are the anti short cycle periods same for small up to big air cond systems if they are all made by the same maker?

Many thanks!

[goshen]

[QUOTE=schow168;184658]Hi Tesla,

Thanks for your advice!

So are the anti short cycle periods same for all air cond manufacturers? If not how and where can I find out how long should this period be?

Are the anti short cycle periods same for small up to big air cond systems if they are all made by the same maker?
Hi
5 - 8 minutes is a good time for most units,
If unit does recycle so often it would seem over sized for the room its in,
Good luck







Many thanks![/QUOThiE]

[Brian_UK]

Most ready made air conditioning units have a built in 'start delay timer' of about 3 minutes.

It is to prevent overheating of the compressor motor windings due to frequent starting.

Every time the motor starts the windings heat up with the electrical load. It then takes a while for the cooling effect of the refrigerant gas to take effect on the windings.

Larger compressors can be limited to 6 starts per hour.

[Gingerair]

Hi Schow 168

In general the larger the compressor the longer the anti-cycle period.

But be careful, minimum run times are often over looked but are almost as important, especially with variable speed drive inverters & electronic expansion valves..

There is some info re this in a Bitzer leaflet somewhere but i can't find it at the moment.

If no one else on this forum can help, may be give them a ring..