HEAT EXCHANGER vs DIRECT PIPING PRESSURIZED SYSTEM

[trailhound68]

CURRENTLY I HAVE MY SETON 100 PIPED DIRECTLY TO MY OIL BOILER, PRESSURIZED, CIRCULATING 24/7, BURNING 24/7. THE ONLY WAY FOR ME UTILIZE A PLATE HEAT EXCHANGER WOULD BE TO INSTALL IT AT THE OIL BLR. THERE I COULD INTRODUCE THE NECESSARY MAKE UP WATER TO THE WD BLR LOOP(WD BLR IS 100' AWAY).
MY QUESTION IS; WOULD IT BE MORE EFFICIENT TO UTILIZE A PLATE HEAT EXCHANGER? EVERY OTHER INSTALLATION SEEMS TO BE INSTALLED THIS WAY.
THESE PLATE EXCHANGERS ARE EXPENSIVE AND WOULD REQUIRE ANOTHER PUMP RUNNING 24/7.
THANK YOU FOR YOUR INPUT.

 

[WoodNotOil]

If it is working pressurized, I might leave it that way. There is usually around a 5* difference in temp when using a flat plate to transfer heat. The plate is usually used to seperate the wood boiler line with glycol or other freeze protection from the interior pressurized system. Do you have freeze protection in your system? I think most OWB's are usually operating at a lower pressure as well. The Seton claims to be a "closed system" which I assume means it is pressurized. That might be why it works without a plate.

 

[jebatty]

trailhound68, try using lowercase. Those CAPS are hard to read and usually mean the writer is angry.

 

[trailhound68]

IT'S WORKING FINE, I WAS JUST WONDERING IF ANYONE HAD IDEAS ABOUT EFFICIENCY. I HAVE NO FREEZE PROTECTION BECAUSE THE SYSTEM NEVER LOSES TEMP. I'M A SLAVE TO IT. I AM PLANNING ON FILLING IT WITH GLYCOL SO I CAN ISOLATE THE OUTSIDE SYSTEM AND VACATE. I DO, OF COURSE, HAVE BACK FLOW PREVENTION ON THE MAKE UP WATER SUPPLY. 'NO BURST' IS ALSO A POTABLE GLYCOL THAT I INTEND TO USE.

ANGER IS NOT AN ISSUE. I THOUGH CAPS WOULD BE LARGER AND EASIER TO READ. THOUGHTS?

 

[jebatty]

ctrl+ increases font size for those who need larger print, and ctrl- decreases font size. Skip the caps.

 

[johnnyb]

I have purchased a GW100 and am trying to figure this out myself. I was planning on going with a plate exchanger and a friend has purchased the same unit and his plumber recomended not using a plate exchanger, instead tying direct to his existing oil fired system. both systems have freeze protection around -15 to -20. what are the advantages and disadvantages of going with a plate? Trying to learn more, help needed...

thanks,

johnny b

 

[trailhound68]

I'm trying to learn also. I have one year with the Seton and two prior years with an older boiler on the exact same piping schematic. I can share my experience with the direct piping scheme. I have had zero problems to speak of. I do, however, wish to achieve longer burn times and ultimately consume less wood. I will hopefully be experimenting with storage and pumps. I am hoping someone will chime in regarding plate heat exchangers and whether they are benificial. My though is that you cannot get more efficient than piping directly from the heat source to the oil boiler which handles distribution. Am I wrong?

 

[Dune]

There are good reasons for doing it either way, but if you can do it without the heat exchanger (flat plate or any other type) it will be more efficient. Heat exchangers waste energy and should only be used if unavoidable.

 

[jebatty]

This is not likely to cover all the points, but in general you would use a heat exchanger (plate, coil or other):
1) to isolate pressurized from non-pressurized. You may have a pressurized boiler and non-pressurized storage; or a pressurized system with an existing oil boiler and a non-pressurized boiler.
2) to isolate a system with two different liquid mediums. For example, dhw from boiler water; anti-freeze in the boiler and water in the rest of the system.

Whether to use coil, plate or other: there are lots of posts on this forum discussing advantages/disadvantages of each. I chose a plate hx for my system because it was much less expensive, it was simple, and my tank did not allow for insertion of a coil. I needed an hx because anti-freeze in the boiler, water in the rest of the system. and initially unpressurized storage (now pressurized).

 

[katman]

How muc h of a flow reduction results from use of a plate heat exchanger? Is is significant enouogh to influence piping size/pump considerations?