Football field snow melt system

Leonard

Just heard on TV about today's game at football field in Kansas. They have a heated underground snow melt system, guess so field will drain and not freeze. WOW, wonder what the fuel GPH on that square footage is.

pecmsg

One 30 sec commercial pretty much covers it!

Erin Holohan Haskell

Here's a recent article about it.

Gordy

Always changing the game, and the rules. All those players from days past that played on frozen ground with -15 with out wind chill.

This is football

https://youtu.be/vGjg7j-qTvw

hot_rod

they put radiant heat systems under ice arenas also to keep the ground from freezing and heaving the rink. Heating and cooling at the same time! Under freezer warehouses also for the same reason.

Gordy

Lambeau field actually had electric coiled blankets used in 67.

DZoro

Green Bay had Wirsbo. Installed I believe in the early 90's . I don't remember what boilers, but manifolds at each end zone
D

Leonard

Tenant here in southern NH poured a outside slab touching building and installed a pair of ~ 10x15 walkin coolers. Coolers and freezer have run continuously for 5 years . Do you think I might run into ground freezing problems?

Not sure how deep foundation on building is.

hot_rod

The ones I have been involved with were freezer facilities that run well below 0F. Lots of heavy forklift traffic which also drives down the frost levels.
-20F in typical facilities as low as -30 in blast freezers.

I suppose soil type and moisture content come into play. Vapor barriers, properly installed help prevent humid air from condensing in the under slab insulation.

Hard to predict what could happen without some engineering

Solid_Fuel_Man

Yes @hot rod_7 I work on a few of those as well. Ammonia mostly too! Typically we use condenser heat circulated in those loops. In arenas we chill the floor to a typical 15F and then a foot or two below warm to 40F to keep permafrost out so the ice can be quickly removed when warranted.

Leonard

Ground under cooler cement slab is clay, dug down first , laid ~ 1 ft gravel over it for drainage/ support. One walkin cooler is ~ 35 degs, other is 0 or -10 maybe.

Doesn't matter much it's done and he's paying the rent. Just wondering what I'm in for. And what if should do anything special as far as warming it up when he leaves. I'm guessing nothing special.

hot_rod

hard to predict if you could have issues. Commercial, low temperature freezers have radiant or some forced air to move humidity and lessen the heave potential

Sounds like not much to be done now. Gravel drainage will help if any trapped water can drain away. The moisture combined with temperature is the condition to avoid

Leonard

Wasn't an expensive install , he poured thick slab ~ 8 +inch with no internal heating. Had his guys errected and bolted together 4 inch foam walls with aluminum skins, DIY. Had HVAC guy install fan evaporators , condensor, pump and tubing

Interesting thing is steel Carriage bolts go thru roof panel to hold up evaporator assembly. Not much ice outside on roof , but ~-4 inches thick ice over bolt heads, heat entry point.

nibs

Bunch a wusses, have played football and Rugby in snow, rain, sleet and hail.................... those were the days.

hot_rod

Leonard said:

Wasn't an expensive install , he poured thick slab ~ 8 +inch with no internal heating. Had his guys errected and bolted together 4 inch foam walls with aluminum skins, DIY. Had HVAC guy install fan evaporators , condensor, pump and tubing

Interesting thing is steel Carriage bolts go thru roof panel to hold up evaporator assembly. Not much ice outside on roof , but ~-4 inches thick ice over bolt heads, heat entry point.

Thermal conductors. The early steel stud homes I worked on would conduct temperature like that. not quite ice, but not a viable construction detail.

pecmsg

Walk In Coolers no protection needed.............
Freezers need protection
Several ways of doing it depending on environment and job.

Leonard

what's the protection?

Solid_Fuel_Man

Most I've seen had slab completely isolated with bluebeard. Exposed blueboard where it was placed vertically in the slab before the pour. I'd think 2" minimum, 4" better! It's expensive to cool stuff down

Leonard

Blue board = styrofoam-ish or drywall ??
Guessing styrofoam?

hot_rod

Leonard said:

what's the protection?

I’d guess any method to prevent the frost level driving down under the slab. Lots of forces involved in ground movement.

Heating and maintaining ground temperature above freezing with radiant, or some air movement options to accomplish the same result.

Heatway chased this market and published some guidelines and design criteria. It was in a late 1990s maybe? design manual I have on my shelf. I visited and did some work on one system in Springfield, MO.