Insulated boxes being installed on F&T traps

Smitdy

I work in a large hospital as a plumber/steamfitter as part of the efficiency program they have recently hired an outside vendor which is installing these insulated boxes on the f&t traps. My understanding of an f&t trap is it's the one place you want the steam to flashback to condensate so insulating it doesn't make much sense to me. Does anyone have a rational explanation of why this is being done?

EBEBRATT-Ed

Interesting. I think it will reduce the heat loss form un insulated traps. I don't think there is any harm in installing them as far as the operation of the trap goes

Smitdy

I should add they run the steam at 14 lb. And some of the condensate lines are missing insulation my thinking is if you insulate the Trap steam could condense into a liquid that is higher than 212F and snap back to steam if it finds any low pressure Zone in the rest of the condensate line after passing through the Trap causing hammer or worse @ the condensate pumps ruining a seal. The Trap is the one place you want the steam to flash to condensate and stay that way, ussually traps are left uninsulated. 

retiredguy

In most of the boiler plants that I serviced the normal steam boiler pressures are close to 100 PSIG. The steam pressure leaving the boiler is determined by the engineer that designed the system. The steam leaves the boiler as a mostly dry steam and and flows through a piping distribution system to be used by many different devices. Those devices reduce the steam pressure through regulators to the pressure required for that device or system. These higher pressures are required so that the steam will get to the whole building and still be relatively "dry". The heating units are a combination of standing radiation, univents that bring in tempered air and heat it to the desired room temperature and through make-up air units that provide tempered fresh air and a positive building pressure. Most condensate systems in a boiler plant that operates with high pressure steam, return the water to the boiler room as a positive pressure. That is just how the system is designed.

It is hard for me to comprehend how they can justify the expense from such a labor intensive operation and material cost to save a tiny fraction of heat. This must have been a thought from a study done by a group of "pencil pushers" as I called them that have nothing better to do. These traps will operate just fine with or without that insulation. You asked if anyone had a rational explanation of why this is being done. Yes, the "pencil pushers" needed to find something to justify their job. (I hope I didn't offend anyone).

Insulating any bare steam line or condensate line would be a much better cost savings than insulating the steam traps.

Smitdy

@retiredguy guy pretty much what I figured, just thought I would put it out there in case somebody with an engineering background had a legitimate explanation.

mferrer

I agree with most of what has been said. It is important to insulate both Steam supply and condensate return. If I try and make economic sense out of the idea of insulating a steam trap, I can only think that lowering any kind of heat loss can lead to fuel savings. But it has to be enough to have a return on investment and it doesn't make sense unless you are guaranteeing that all of your insulation issues are quickly addressed. 
The other thing that comes to mind ia the most important economic issue re: traps is the life expectancy (and service) of the thermostatic element. What good is the microscopic savings rendered by a removable trap insulator if there is not a good maintenance program in place. 
So, in my opinion, installing test tees (with valves) on the outlet of every trap (so you can periodically test them) is worth a lot more than removable trap insulation kits. The kits are not a bad idea if you have everything else in place. Good maintenance/preventative program, 100% insulation and most importantly, effective monitoring with swift acting protocols in place.

pecmsg

Efficiency Company AKA Military Intelligence! Doesn't exist. Last facility i was at the energy savers shut down fan motors 10 mins an hour.............Not good on a DX Systems! Any savings were used up in blown compressors!

dopey27177

I used to do hospital work. The only places they used insulating boxes on exposed steam traps was in kitchens using steam to make soup and cook foods.

Typically the steam traps were F&T. When you insulate the trap the thermostaic element may not open as the steam trap body could be at much to high a temperature to allow the element to open.

Jake