makeup water system connected to water supply for closed chiller system
makeup water system connected to water supply for closed chiller system
(OP)
Gents,
We are in the process of designing closed chiller that will be connected to teh water supply system. To prevent back flow I have been going through some document on the internet, but I noticed that there is a requirement for a double check valve. I also have an existing system here, but I do not want to copy it as I noticed this one does not contain a double regulation valve and could have the possebilty of back flow.
I have two questoins;
1) can you tell me how to design a makeup system that is direct and perminent connected to the water supply.
2) see attached pictures, would this be acceptable system or are there difficulties?
We are in the process of designing closed chiller that will be connected to teh water supply system. To prevent back flow I have been going through some document on the internet, but I noticed that there is a requirement for a double check valve. I also have an existing system here, but I do not want to copy it as I noticed this one does not contain a double regulation valve and could have the possebilty of back flow.
I have two questoins;
1) can you tell me how to design a makeup system that is direct and perminent connected to the water supply.
2) see attached pictures, would this be acceptable system or are there difficulties?





RE: makeup water system connected to water supply for closed chiller system
I would recommend a separate shut off valve upstream of the backflow preventer, with a strainer (to prevent any particulates which could foul the backflow preventer). Some would put a check valve upstream of it to mitigate any pressure swings upstream of it (to keep the backflow from sputtering.
RE: makeup water system connected to water supply for closed chiller system
Water Utility calls this cross-connections since it connects your chilled water (with toxic corrosion inhibitors etc.) with their water system and they want to make sure you don't spill back the toxic materials.
RE: makeup water system connected to water supply for closed chiller system
though, when i see this photo, i recall good old times when i used hammer as engineer's supervision tool - to destroy things like this on the spot, without discussion
moreover, i am not sure what this central device presents. is that pressure reducer? you likely need to reduce pressure from water network - in german-based specs testing pressure of water supply systems is 10 bar, for chilled system it is 5 bar.
anyhow, this is not a way to establish pressure control in your chilled water system. you are on the right track to not copy old system, so continue that way and do not copy concept of this old system.
direct automatic make-up would be acceptable only for some rugged industrial systems where there are no other options. you do not want to plan for system which will leak all around and have automatic make-up - that is finally not closed system at all, isn't it?! if maintenance guys complain to thoughts like these ones, fire them.
if you cannot live without automatic make up, than you need electronic controller-based pressure control system with digital output for solenoid valve which will open make-up when needed. backflow preventer serves only to protect potable water supply.
RE: makeup water system connected to water supply for closed chiller system
RE: makeup water system connected to water supply for closed chiller system