Combination Fire Protection/Heat Pump system (ME)

Mark Eatherton1

I sat in on a meeting of developers and architects yesterday discussing the virtues of the heating/cooling system for a subsidized housing project to be built this coming year.

The developer wanted to go the CHEAP route, that being all electric with thru the wall PTAC cooling. The architects/designers wanted to the green route, unsure what route it was. I sat there and listened to the developers and the architecs arguing dollars over environmental common sense thinking to myself, they're using HUD dollars to build this place, and those are MY dollars.

I finally spoke up and asked them if anyone had considered the possibilty of upsizing the fire protection system (plastic), using it to transport low temperature water (50 to 75 degree F) installing natural gas condensing boilers for the heating of the water to 75 degrees F, installing individual water source heat pumps for heating and cooling in each apartment, and using the snowmelt systems around the property for heat rejection during cooling mode, with maybe a small cooling tower for back up.

The room fell silent... They all agreed that it was an excellent idea and wanted to know why nobody had ever proposed it before. They agreed that it would be the GREENEST system available, without busting the budget.

I know I've seen systems like this before, and in fact have worked on them, but can't find any reference to them on the internet. Anyone got any resources, or am I thinking WAY outside of the box.

Thanks for the input as usual.

ME

hr

I remember reading

about a combined system like this in Missoula, Montana. As I recall.

I need to think where I read about this, it may have been in a NFPA journal or newsletter when I was a member.

Check the nfpa website and queary there. A system like this would fall under their juristiction I'll bet.

hot rod

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[Deleted User]

I'd call the local distributers

for the equipement you may use. See what they say.In my area they"ll even design the system. But, the use of the fire suppression system, I'm conserned with. I know in N.J., we can't use it.

GMcD

FP System as hydronic loop

There may also be some references cited at Dr. Mumma's site at http://doas-radiant.psu.edu and he has one paper in the Technical Papers section at http://doas-radiant.psu.edu/7-4.pdf

The fundamental issue will be to get the local Fire Folks to buy into it. In Canada we can't even think of doing this-there is no way the fire folks would allow it the way our Codes are currently written up.

I have a concern about using the snowmelt system as the heat rejector in summer cooling mode - the snowmelt pipes are "near surface" and would actually be acting as a solar collection system, and be quite a bit warmer than the ambient ground surface temperature/air temperature compared to a conventional horizontal geo-exchange field that is normally buried 8 feet down. You'd be trying to reject heat into an already warmed geo-exchange(snowmelt) field that's been collecting solar load all day. Even if it's on the north side, it will get some sun late in the day when you want to reject heat from the buildings. The snowmelt system might be able to be a good heat rejection source by about 2AM on clear nights as it radiates away into space and gets cooler than ambient air. It will be a time-offset issue - if you can delay rejecting heat into the snowmelt field due to the volume of fluid in the hydronic system (allow the heat to build up in the system until after midnight) then it might work, but being a P.Eng. I'd still put in the fluid cooler so I could sleep at night. The key will be balancing the heat rejection load with the area of the snowmelt heat rejection surface/volume/heat rejection rate.

Your meeting with all those high priced professionals continues to show the fear of new ways of thinking for professional building designers. The lawyers and insurance agents are training all of the professionals to avoid risk, so anything "new" is deemed "risky", and doesn't even bubble up from the brain cells. Heck- it's straight physics, and the laws of physics are pretty low risk, they don't change.

Mark Eatherton

Bump up...

THought maybe some of the weekday crowd might have missed this...

ME

JimGPE_3

Tri-water

This is called a tri-water system. You'll find more in Google using that name. I've worked on one here in Pittsburgh. Twenty years later and it is still up and running.

At that time there was some guy in Alaska who owned a patent on the design, and if you built one, you owed this guy a royalty fee.

There's a lot to think about, from the pressure rating of all components to using the sprinkler system for the RETURN water only, so you can use a check valve to stop the water if the heat pump connector hose should burn up, etc. etc.

Its a great system. There's only two pipes, and you don't normally have to insulate them. Any one zone can be in heating or cooling at any time - try that with a normal 2-pipe fan coil design.

Let me know if I can help.

BTW - I gave some thought to a quad-water system - water out in the sprinkler piping, back in the electrical conduit....Nah, just kidding.

Weezbo

That comes from doing Your Own Thinking Good Idea!

Not to elaborate much further however I would say at Least one other person has entertained the logic on this topic *~/:)....The King Snivelers will be the first to object on some meaningless hypothetical...Here is where i like the nikki thing Just DO IT ! *~/:) and Thank God this is America an we Can have our own opinion ....it aint like the old days when "if You Had an opinion,...I Gave it to You!" ))

JimGPE_3

Re. Mike's comment

There are no "distributers" per se. This is not a matter so much of equipment as it is design. Its the same components, water source heat pumps, hoses, check valves, boilers, evaporative coolers, etc. that you would use on any wshp system. What you want is someone who has applied these components in this way before. They are not thick upon the ground.

Mark, if you get serious about this design, you will need to keep refining your schematic. Some issues that come to mind:

Unless this is a computer data center with almost no heating load ever, you will never have excess heat to reject when your parking garage slab needs it. The building will need it first.

The piping system is not really a loop. There is a dedicated supply piping system, and the sprinkler system is the dedicated return piping.

Copper piping will work as well. And I know of no reason why the piping system must be non-ferrous. The one here in Pittsburgh is schedule 40 BS and it was built in the late '70's.

Like I said, if you get serious about this, I'd be willing to chat with you. What part of the world is your business in?

jim_49

Sounds like a great system, but after all the P.E.s, the archect. lawyers and chiefs are gone and have gotten paid, whose left??? US, the service techs.My advise is to keep with a system that is user friendly.{tech friendly} and works, unless all the heads involved in the project leave their home and cell phones on the wall next to all the wall switches so when something or everything doesn't work just the way it should, We have someone to call.

Mark Eatherton1

My world...

Thanks for the replies Jim. THe tri-water did get better responses than my previous efforts. I'm in the mile high city of Denver. I spoke with the main person in charge of approving fire sprinkler designs for the city today, and though open minded, he said the city does not allow any "domestic" uses of sprinkler systems. I asked him to define domestic, and he said its anything other than fire protection. Looks like I may have an uphill battle on my hands here, but I'm willing to instill the effort to at least try and see if I can get them to see things my way. If not, at least I can say that I did try. If I never try, I'd never know. I may be in touch. Here's my most recent hand at minimizing hydronic influence on the fire protection system. Give me your thoughts. THANKS!

ME

Mark Eatherton1

Thanks Geoff...

Yoour concerns are duly noted. Actually, I have access to a LARGE underground parking area that would also serve well as a heat sink. I'd still back it up with a small rejection tower though.

ME

JimGPE_3

Better

But again, it is not really a loop in the sense that the supply and return lines are connected. The supply line is a dedicated pipe run. The return water is the only water that flows in the sprinkler line. Also, normally you keep the water flowing through the sprinkler mains in the same direction, cooling or fire duty, you just connect to one end with the city water and the other end with the pump suction.

You're close enough for horse shoes, so keep going and we'll talk if you get the job, if you want.

If you REALLY have your heart set on convincing these guys, and you have some cash in for those rascally engineers (that would be me) we can chat about me going along to the code official's meeting and sharing my experiences, as well as the status of the very high profile project here in Pittsburgh. Who knows, it could open up a whole new market for you there.

Whatever. Its entirely up to you and how hard you want to fight city hall (and how open they are to new ideas once they understand them).

But the difficulties are in our heads. At the end of the day, this is just a water source heat pump system, much like any other, its just that the return mains have sprinkler heads on them! No biggie (even for the techs upon whom we thrust the burden of longevity!)

bob_25

your favorite boiler

Mark, the hotel denver in glenwood spgs has a wshp system piped in pvc. two pipe rev return and two of your favorite (rite) boilers. it was designed by abeta (spelling) engineering in denver. i wonder about the suitability of the orange pvc? bob

Mark Eatherton

re-bump.

ME