more questions..

[josh]

Found some good pictures on this website:

Risers and Run-Outs


On the 'modular pipework' section the 4 pipes going to fan coil units, two are just flow and return from a heat source like a boiler and are the other 2 from a chiller so in summer they can provide cool air, is that right?

Also what is the basic principle on how a chiller works?

And wondered this before, why do you loop the pipe before pressure gauges?

Any other info on it all would be good, am willing to learn as always!


Thanks.

 

[Ermintrude]

Yes that's right. It's a bit old hat. Decent jobs have ashp now. Chilled is a pita! Basically water is chilled externally by a "chiller" big coils with fans and refrigerant. Ahu brings in or re circulates air, heats de humidifies and filters.

Some systems don't have right controls so try to heat and cill at same time. Others are poorly insulated..... Office dwellers assume there is a leak..... Really it's condensation on steel chilled water pipes. All pipework should be lagged even that in plant room. You know the systems inefficient when plant room is at 55c

 

[josh]

Thank you Ermintrude, much appreciated.
Always good to learn something new.

 

[missplumb]

the loops in the pipes are pigtail siphon tubes. used mainly on steam systems to protect the pressure gauges from excessive heat, they also act as a condensate trap. You can also get them as a "U-tube" siphon, dont really need them on LTHW systems. and Ermy has already answered your chiller question.
Looking at some of them pics, they have put plenty of strainers in the pipework but only have a commissioning set on one side for isolation.:uhoh2:

 

[josh]

Thanks for the reply missplumb,
you wouldn't have a commissioning set on both sides would you?

 

[missplumb]

No you wouldn't,but it would make sense to fit some sort of isolation valve so the strainer cam be cleaned at service without having to drain large chunks of the system.