As Jim said, there is no way to get 200-250K out of 1" pex without something on the heat emitter side that can create a
huge temperature drop.
Working with an optimistic 8GPM available through that length of 1" pex, each 1* of temp drop would equal 3998btu's. So to hit even 200,000 you would need something on the order of a 50* drop to generate that kind of load at that flow rate.
Only way you could hit that would be dumping 8gpm into a cold concrete slab. Supply to return on the boiler would have to show a 50* differential to soak up 200,000
8gpm x 8.33# of water/gallon x 50* x 60 minutes/hour = 199,920btu.
If those indeed are the parameters you need to hit, you will need a large heat exchanger to achieve that goal.
Using the following parameters this is what I come up with:
Boiler (side A) of the heat exchanger IN @ 180* ----- OUT (back to boiler) @ 160*, flow rate required = 20.5gpm
Load (side B) of the heat exchanger IN @ 120*------OUT (back to system) @ 175*, flow rate required = 7.4gpm
Heat exchanger size 5"x12"-50 plate with 1-1/4" ports will do the above.
Also should mention that the head developed by the HX will be .7 Ft. on Side B and 4.6 on Side A
So it's doable IF (big IF) your system can generate that kind of a temp drop. Once you start to decrease the
![DeltaT ::DT ::DT](/talk/styles/default/xenforo/smileys/deltat.png)
T on the output or load side of the HX, everything goes out the window.
If your system can only generate a more normal 20* drop you will be limited to a range of 70,000 to 80,000 btu's due to the size of your pex.
The remaining question is....(drum roll).....what does your actual heating system consist of.
Coil in a furnace? Radiators? Baseboard? Heated slab?, Domestic hot water load? Combination of the above?
So to sum it up, I have to say that realistically speaking, you will not be able to transfer 200,000 btu's out of your boiler.
![Down :( :(](/talk/styles/default/xenforo/smileys/downer.gif)