Actually a question for all who have experience, but wanted to catch Rob’s attention.
I’m near having the remainder of the system shipped for garage floor. The company sent mechanical drawings for my approval…primarily for placement of the gear to assure fitting in the space available.
The layout works fine, but thought I’d post drawing here to run past y’all before I give my blessing for them to fabricate.
See anything that raises questions or concerns?
The seven loop manifold mounts on the opposite side of boiler wall (SIP) and saves running all the pex loops through separately (there are two heating zones). I’ll box that in to protect from damage. Boiler itself will be in separate mechanical room with compressor and dust collector.
What say you, experts?
PJ
Everything will be okay in the end. If it’s not okay, it’s not the end.
Replies
I've never seen a bypass doing opposing flow with a zone return before, but honestly I don't know if that any kind of potential issue or not.
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
Thanks for eyeballing Rob, I'll ask them about it.
PJ
Everything will be okay in the end. If it's not okay, it's not the end.
FYI, here's explanation I got from them. Sounds like a good way to go if its reliable.
The bypass valve extends the life of the secondary pump. It takes a few seconds for the zone valves to open completely. If the pump is pumping and the zone valves are not fully open, the pump works very hard. The bypass will snese the pressure and give the pump a place to pump until the zone valves fully open.PJ
Everything will be okay in the end. If it's not okay, it's not the end.
Oh, using a bypass is absolutely a good idea. I've just never see one piped so that flow through it is directly opposing the flow coming out of a zone. Again, I'm not sure that's actually a problem, it's just different and I'm not sure what the ramifications of that are, if any.I can imagine in my head that flow going through the bypass leg could push against flow attempting to leave that zone that is piped into the same tee, artificially increasing its resistance to flow under certain conditions. Then again, I can imagine talking cats that rise up and form their own society o'er the realm of man as well... doesn't make it real ;) Even if my imagination were correct, even that wouldn't mean it was a problem for sure. But I'd love to hear what the company says about the physical piping of the bypass leg. It may be as simple as "there is no problem with that", or there might be a much more interesting discussion to be had.but then, I"m a big dork for this stuff, and maybe you're just happy if it works ;) It should.-------------------------------------
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
Now I don't know much about hydronic heating systems.But can anyone tell me why there are two pumps?Now if there where several loops operating at different tempatures with mixing valves or a heat exchanger for domestic water heaing or other "special" applications I can see the need for multiple pumps.But this appears to be a fairly simple system..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
that's called "primary secondary" piping. It decouples flow through the boiler from flow through the radiant system.In some cases you can skip that with the MFG's blessing, if you can guarantee you are within acceptable flow boundaries whenever the boiler is running, but generally it's just much easier to run two pumps, especially as you add more zones or if the zones are relatively small.-------------------------------------
-=Northeast Radiant Technology=-
Radiant Design, Consultation, Parts Supply
http://www.NRTradiant.com
I think the idea is to avoid cold water returning to the boiler. This causes condensation in the firebox and corrosion and sludge buildup (at least for oil boilers).
Okey dokey, I see where you're coming from. Not the bypass so much as the way it's installed. I can imagine the same thing, kinda like two people trying to go through the same turnstile simultaneously. So you're thinking an additional tee downstream from the manifold dedicated to the bypass?
I'll ask them about it, they're pretty patient with my questions, and I've had plenty :).
Gee, Rob I'm glad you're a dork about it...exactly what I need! I've read your many posts here with interest. Didn't want to get it over my head, so I entrusted the engineering to someone else, didn't want an expensive reminder of my own boondogle.
The closer I get the more completely I'm jazzed to get the system going, the whole concept is something I've been dreaming about for some time. I've promised DW a warm place to store the car, no more scraping windows next winter, and I get a much anticipated workspace.
The talking cat thing.....well, I'll hafta ponder that some.... PJ
Everything will be okay in the end. If it's not okay, it's not the end.
FYI, my question about the issue you raised:
Envisioing how it works, I look at the zone return opposing the bypass and wonder if it would ever create a deadlock of sorts when both are flowing into the tee. Now, understand I'm not an engineer and I'm not really qualified to design this stuff, just interested in the dynamics. If it's no biggie, I'm content with that.
And Wayne's response:
The deadlock should not be a problem becuase the flows out of the pump will equal the flows being returned. The shop will place an air elimiator on that line as well--just for safe measure. We will let you know when the system will be ready for shipment etc.
Thanks,
WaynePJ
Everything will be okay in the end. If it's not okay, it's not the end.