Why would they need 10 PSI steam pressure??

JUGHNE

A hospital has 2 Kewanee M-265-KGO steam boilers. These are 80 HP rated at 2,650 MBTUH each. They have hi-low burner controls. Only one boiler is on line at a time.

The maintenance personal believe they need 10 PSI, they don't know why, that is just the way it has been for 30+ years. (Handed down thru numerous personal). The steam does not leave the room except for humidifiers that are seldom used. The DHW has a steam/water HEX. The heating coils have a steam/water HEX also. HEX's are right near the boiler.

So what to look for that might require that much pressure? There are some cases where the condensate must be lifted, but I don't believe there is a 20' lift requirement in the system.

Any input appreciated, thanks.

ratio

Was the steam ever used for sterilization? You might be able to get original build documents for a hospital - those kind of places seem to take document retention more serious than others.

JUGHNE

That's a possibility, I did want to look at original prints. Just wanted some heads up as what to look for. The maint guy thinks I ask too many questions. And it works so why change anything, right?

ratio

I'm just guessing. But I too ask too many questions.

If I know how it works, I also know why it doesn't work.

JUGHNE

I believe they had steam coils in air handlers, but that may have changed thru numerous remodels.

I might get there tomorrow, it's just 10 miles away.

Pumpguy

In addition to sterilizers, there could be laundry, and steam tables for the kitchen and/or cafeteria.

IME, hospitals are notorious for higher than necessary steam pressure and resulting high condensate temperature. I try to recommend splitting the high temperature process steam condensate from lower temp building heat condensate. Another scenario could be running the hot condensate through a heat exchanger to reclaim some of that heat.

I sometimes find vacuum pumps on these systems, and customers complaining about poor vacuum performance. When this is the case, I recommend splitting high temp condensate from low temp vacuum return condensate. I explain that high temperature condensate and good vacuum pump performance is an impossible combination. Some do consider making this change, but unfortunately most don't. I feel like I'm a voice crying in the wilderness.