Chilled water riser Open loop or closed loop?

[econ2016]

I have a question:

Condo building chilled water risers provide Chilled water for fan coil units. But at the lowest floor, there is a cleanout for each riser. This chilled water system can still be seen as closed loop? or open loop? This is important for selecting chilled water pumps, correct? Thanks!

 

[EnergyProfessional]

Never seen cleanouts on a system that is not sewage... HVAC typically is closed loop and dirt is collected at strainers, and dirt separators.

I assume under normal operation the cleanouts are sealed.

 

[BronYrAur]

Perhaps they are just riser drains. I can't imagine that you have an open system. This is chilled water, not cooling tower water, correct?

 

[LittleInch]

Drawing / sketch required.

Sounds like a closed loop, but closed lops need expansion vessels and a pressure feed to maintain positive pressure at the highest point. your system got those?

We don't know.

The cleanout is just a drain connection?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[econ2016]

Also, this building used pressure break in the chilled water loop. Anyone knows the chilled water pressure break is necessary for the chiller water loop for the 50stories building?

 

[Buildtech2]

Pressure break heat exchangers are needed for high rise towers to minimize the casing pressure of chilled water pumps and also pressure rating of chillers, condensers and valves. The maximum pressure rating of chillers and condensers available in the market is up to 20 bar. the pressure rating of valves can be higher. This is the main reason for providing pressure break heat exchangers in high rise towers.

As advised by others, chilled water loop will be closed loop circuit. I believe you are referring to the drain point which will be installed at the lowest point of chilled water system.