Another liquid hammer problem

[captaincascade]

Hello all

Ive cruised this forum for years, only just joined. Thanks for having me. I work for a company that services and builds scientific refrigeration equipment mostly cascade systems. We recently built a large -30c walk-in. Its a redundant system with 2 seperate refrigeration systems, that cycle every 12 hours. Each condensing unit feeds 2 evaps. 2 evaps on 1 side , 2 on the other. The systems are electric defrost and each system has a subcooler piped so the liquid goes through the subcooler before it feeds the evaps. Each evap has a sv and a txv.

Now my problem is an incredibly severe hammering on 1 of the evaps liquid line. Keep in mind...only 1 evap, on 1 system ... the other system is fine and identical.

We changed both the svs and the txvs, to no avail

When installing these systems we installed a shader valve before the sv for evac and perging. When i hook up my gauges to this shrader the sound goes away. My boss had me, basicly take a piece of 7/8 copper, cap 1 side, and connect it to this shrader. This was several weeks ago and i only recently found out the problem is ocurring once again. I realize that between my hose and gauge, i am allowing a certain amount of expansion and contraction. After reading through your forum im worried my solenoid valves may be too large.

I was thinking an easy fix might be to connect a legth of cap tube to my shrader access and have that feed to an expansion tank, i could easily mount above the cieling. I realize someof you will want specs... you'll have them i the morrow.

thanks for your help. this is driving us crazy!

[Tesla]

Hi captaincascade
jsut a thought with the fluid hammer issue you could change the solaniod valve to a motorised version - danfos or something or look at your pipeing layout. If both systems are identicle your pipeing length or bends (charicteristics) would be the only difference.

[taz24]

Hello all

Ive cruised this forum for years, only just joined. Thanks for having me. I work for a company that services and builds scientific refrigeration equipment mostly cascade systems. We recently built a large -30c walk-in. Its a redundant system with 2 seperate refrigeration systems, that cycle every 12 hours. Each condensing unit feeds 2 evaps. 2 evaps on 1 side , 2 on the other. The systems are electric defrost and each system has a subcooler piped so the liquid goes through the subcooler before it feeds the evaps. Each evap has a sv and a txv.

Now my problem is an incredibly severe hammering on 1 of the evaps liquid line. Keep in mind...only 1 evap, on 1 system ... the other system is fine and identical.

We changed both the svs and the txvs, to no avail

When installing these systems we installed a shader valve before the sv for evac and perging. When i hook up my gauges to this shrader the sound goes away. My boss had me, basicly take a piece of 7/8 copper, cap 1 side, and connect it to this shrader. This was several weeks ago and i only recently found out the problem is ocurring once again. I realize that between my hose and gauge, i am allowing a certain amount of expansion and contraction. After reading through your forum im worried my solenoid valves may be too large.

I was thinking an easy fix might be to connect a legth of cap tube to my shrader access and have that feed to an expansion tank, i could easily mount above the cieling. I realize someof you will want specs... you'll have them i the morrow.

thanks for your help. this is driving us crazy!

Could the shrader be interfering with the flow??

taz.

.

[Yuri B.]

Hello. Are there line receivers ?

[Yuri B.]

Of course, there should be - maybe to put a larger one on this particular system ?

[nike123]

Could you post refrigerant diagram here?

[tony--1]

how close is the sv to the exp valve ?