Economiser port

[Rajkumar]

Dear all,

I have a problem with howden screw compressor, My problem is the economiser port gets red hot.

I had connected the oil line from oil separator to the economiser port.

The refrigerant is ammonia.

Can any one suggest what is the reason for this and how to solve this problem.

regards, and thanks in advance.

[Brian_UK]

Don't know this compressor or your pipe layout but it sounds as though hot gas is coming straight back to the compressor.

Is the oil return line cool, warm or hot?

[Rajkumar]

Oil line is warm

[RANGER1]

Have seen this on other machines also .

I think its same gas being recirculated in and out of this port , so gas is getting more and more superheated .
If oil return is not returning this will happen especially on VFD units when at low speeds .

Best is return it into suction if possible .

[guapo]

What is the type of your oil cooler? Oil temp? Oil pressure? discharge pressure?
If I'm not mistaken the pressure in economizer port is the pressure between your suction & discharge pressure.
Make sure your oil pressure is higher than economizer port.

[Ambrish_bajpai]

Dear all,

I have a problem with howden screw compressor, My problem is the economiser port gets red hot.

I had connected the oil line from oil separator to the economiser port.

The refrigerant is ammonia.

Can any one suggest what is the reason for this and how to solve this problem.

regards, and thanks in advance.

I think you have connected secondary oil seperator , coalescing element , drain to economiser port. In my view , you must connect it to suction line with restriction orifice in between so that pressure can be equalised to suction line. Hope this solves your problem. Orifice must be sized for the required pressure drop.