40 panel radiators

Floyd_5

many panel rads....
I have a rather large building to do....actually a retrofit of a very old steam system, and yes I know that it will kill some of you that I even THINK about dismanteling an old steam system, but the steam piping is totally shot and so now I need options and feel that hot water and panel rads is the way to go.
So now, I got about 200' for the longest run from the boiler room to the furtherest room, how would you pipe it???
Found an article by Siggy, seems he kinda would go with manifolds...and one by Dan that's in the HTT section of this site, that seems to infer that if piped right a loop could be done with no monoflo tee's.
After reading all this I have more ???'s than anwsers......

Manifold's......Loops.....monoflo or no.....

What say ye????

Floyd

Mark Eatherton1

Been there, done that...

and the field piping depends on the space available, and the locations of the radiators. I've done it all three ways. Long running S&R distribution piping, remote manifolds and one pipe. They all have their application. It depends on how many pounds of sugar you need to fit into a given box:-)

As for advantages and disadvantages, the long running piping is sized based on flow. If done parallel, it can be cumbersome to balance. If done parallel reverse return, it will be automatically balanced, but will cost slightly more due to reverse return.

If done with remote manifolding, you still have to have substantial S&R piping, but less branches. Still should be piped in reverse return.

If you go one pipe, you have to adjust radiator size based on temperature drop, and the radiators end up being much larger in some cases depending on the length of the run and the load carried.

For the ultimate system, I'd recommend running copper S&R mains parallel reverse return mains in Rigid ProPress with PAP branches, converting back to copper just before floor penetrations (vacuum cleaner syndrome).

Set the bottom end up as P/S with the condensing boilers as secondary inputs. Size the radiators for 160 degree max temps with a 30 degree delta T and your boilers will be in condensing mode for 90% of the time. Do an outdoor reset, and variable speed primary pump based on delta T or delta P(eliminates need for PAB, decreases parasitic power waste and excessive wear on system).

Mount individual TRV's on the radiators, and watch the fuel bills reduce by 40% MINIMUM.

For DHW, pipe large heat exchange surface DHW tanks (phase 3, TurboMax/ErgoMax) parallel (one per boiler) to the secondaries and let 'er rip!

Sounds like a fun project to me...

ME

Floyd_5

A variable pump and delta P????

what for control???? Can't say as I ever saw one....
But yes, reverse return, with branches,TRV's, reset, and a pump working off of delta P, sounds very interesting, indeed!!

Enlighten me o wise one......

tim smith_2

delta P control

Mark, i have been looking into a control strategy like this for awhile. Do you use the Heatimer control with delta P and a B&G variable speed pump. The other pump i have inquired about is a Grundfos Alpha pump i think it was called. Only found it in the european market although. E mailed Grundfos to see if they plan on bringing to the US any time soon. Reply what you have done if you will, thanks Tim.

jalcoplumb_2

I like the manifold

method. I use it a lot when converting old Radiator systems.

Check out the post "Munchkin Work in progress". I only have 11 Radiators but the system works great. You do have to watch the length of your runs. I use 1/2" pex and the manifold I use has a fitting for 3/4" pex. It is 1 1/4" and has built in flow meters to help bal. the system.

Time wise the manifold and pex are a snap.

Give me a call if you want to chat about options. 609.304.9749.

Mark Eatherton1

Variable Frequency Drives...

Put Variable Frequency Drives into a Google seacrh window and see waht happens...

Better yet, put Honeywell Variable Frequency Drive in their and ENJOY.

Grundfos does have one on the horizon...(I've been waiting for 6 years now...)

Taco has one in testing.

I'm not 100% sure, but I think tekmar may have something up their sleeve (I've been preaching, er I mean TALKING to them forever...)

The days of the old clunky VFD are gone. Solid state technology has brought this technology to the forefront for the medium sized job. Hopefully, it will be readily available for the small size jobs in the near future.

Personally, I've modified a tekmar control and used it on my own house as a variable speed pump control. It worked quite niftily. I had it set up as a gravity circulation enhancer.

ME