Help with storage plumbing 2.0

[warno]

In my last thread I feel alot of things got lost in the discussion. I'm starting a new thread with my newest drawing. I would like everyone to please review and post any comments or suggestions.

I'll post again my plans for this system starting at the boiler.

Keep in mind all pumps are grundfos 15-58 circs. except for the storage to house pump.

The boiler pump will run from the boiler shed into the garage to the plate HX then back to the boiler. My heat dump system will be tied into this loop. If the return line to the boiler gets too hot my heat dump will pull off the boiler supply line to a water to air HX that will have a blower on it to cool things down. In a power outage my boiler has a damper that will shut so an out of control situation can't happen. My boiler protection valve will also be on the boiler to storage loop.

Now from the plate HX

My storage tanks will have a pump on the return line after the manifold connections to push water up through my plate HX to get my counter flow. I'll be running reverse return with step down manifold plumbing on my 3 tanks. I will have my garage heating loop pulling from the supply manifold up through my water to air HX in the garage. The pump for my garage loop will only run with a call for heat.

My storage to house pump will be a setpoint T pump and it will be in the house crawlspace pushing into my house manifold. From my house manifold I'll be pumping out to my HX in my furnace. The "storage to house" pump and HX pump in the house will only run with a call for heat. I have a 90 feet long underground run to the house manifold and it was suggested to run a setpoint pump for that run which is why i drew it that way.

A question I have about running to my house is, my plumbing has to run about 15 feet across my exterior wall in the garage before going into the underground line. Could I run this line in the wall through the 2 X 4 studs and then use closed cell foam around the pipe? Would that be enough insulation to prevent freezing? Or would there be a better way to hide this run?

Here's the new drawing

 

[huffdawg]

What size pipe or tubing is it ?

 

[warno]

For the in wall question? It would be 1" copper pipe.

 

[huffdawg]

For the in wall question? It would be 1" copper pipe.

I think it wouldn't be a good idea unless the pipe is exposed to a heat source from the inside . But you want to insulate the whole pipe because you don't want to lose heat from the pipe when it is in operation. I wouldn't do it particularly in your climate.

 

[warno]

Well that's disappointing. I guess I'll be doing something different with that.

Back to my drawing now, could anyone tell if it's ok?

 

[maple1]

Is the HX the only load in the house?

I am not seeing the need for the two pumps on that circuit - or the manifold if only one load. If more than one load, (or if making a place for future loads) I think two manifolds would be the way to go. One for supply & one for return. With one pump that gets called on demand.

 

[warno]

There will be future loads such as DHW and possibly some radiant floor.

So run the single storage to house pump to a supply manifold, Then use zone valves to direct heat to the loads which return to another manifold?

 

[maple1]

That's how my system is set up.

One return manifold, one supply manifold. Zone valve on each load. One pump that starts when any zone valve opens.

I don't have the distance between loads & storage that you will though - that part I'm a bit unsure of, on how good it will work in demand-only pumping. It might be OK, just that each time the pump starts it will send a bigger slug of cold water to storage. But that's up against the catch-22 of running the pump all the time, which will destroy your tank stratification.

 

[warno]

How long are your runs to the load?

Another concern of mine is my expansion tank tee fitting, when my HX to storage pump is running will it push water up into my expansion tank?

 

[maple1]

No. As long as the expansion tank is closed/pressurized.

Also think I mentioned before, I would likely T in the expansion just upstream of the boiler hx - storage circ.

My runs to load are very short - zone valves are like 6' from boiler & storage.

 

[warno]

My expansion T'd into my supply manifold in between my tanks and my pumps isn't a good location?

This pressurized storage design is getting the better of me. Lol

Which zone valves are a good buy?

 

[warno]

Another thing I've been wondering is, how far from the floor should I keep my tanks for insulation proposes?

 

[Buzz Saw]

Well that's disappointing. I guess I'll be doing something different with that.

Back to my drawing now, could anyone tell if it's ok?

Could you just tuck the insulated pipe right up next to the ceiling? Up out of the way would be nice.

 

[warno]

That was going to be my only other option. I'll just build a small false wall cavity and route my pipes through that up at the ceiling level then insulate the crap out of it.

 

[warno]

Anyone else have any input on my new drawing?

 

[Buzz Saw]

That was going to be my only other option. I'll just build a small false wall cavity and route my pipes through that up at the ceiling level then insulate the crap out of it.

This is my plan when I route my lines in my building. Lots of other decisions to make prior to running pipe.

 

[lotawood]

I was thinking if your expansion tank was tied in on the cold tank pipe, before the pump, might be better.

I think that would be the recommended location for a pressure (bladder) tank. Just before the pump. I don't know if an expansion tank would be recommended in the same spot.

It looks like you got a heat pump or is that heat dump? Seems like the three tanks would be a good heat dump. But every now and then I get hotter than I should have, and a heat dump is not bad. My manual heat dump is I turn the thermostat up until the boiler is done.

 

[leon]

Well that's disappointing. I guess I'll be doing something different with that.

Back to my drawing now, could anyone tell if it's ok?

=============================================================================================



If you will forgive the draftsman in me please clean up your drawing.

About the expansion tank, If it is a steel expansion tank your gauge and drain cannot be installed there.
The reason is these tanks do not require a gauge and the drain is brass fitting on the airtrol valve under the tank.

 

[warno]

Sorry for my poor hand writing and drawing abilities.

It is a heat DUMP zone. I just planned this zone just if my boiler is still burning and the storage is up to temp. I'll either be sleeping or at work while the fire is going so I wouldn't be able to keep an eye on things.

I planned on putting a few different gauges in, in various areas. I didn't see any reason not to put a drain in my expansion tank, it's only another fitting for me too weld in, no big deal.

I'm in the process of redoing my drawing once again. I'll be posting it up soon.

 

[warno]

I redid my drawing, I got a hint from the other site to go with a hybrid design. So I redrew everything with that in mind.

I also added a zone valve at my heat dump instead of a circ, and I added a supply and return manifold on the house zone. I felt that with the length of run to the house and the possibly of future loops in the house I will zone with circulators there.

I went basically with this drawing from Caleffi



And here's my drawing, please let me know if it's good or what to change or At least if I'm getting closer.

P1, P2, P4, and P5 will be grundfos 15-58 and P3 will be a Taco viridian VT2218

 

[maple1]

I am thinking you might be able to get by with just one pump on house to storage loop (rather than p3 & p5 both). But the longish run has me uncertain. I guess you could always add or subtract one later to tune things in. Or vary pump speed with a variable speed pump. There's a couple other catch-22's there, in that a W-A hx usually needs somewhat higher supply temps, but more flow might likely upset storage stratification. Thinking an oversized W-A hx would help out a lot - I would definitely go big there in this case.

Also on the dump zone - a 'proper' one will have the ability to flow when the power goes out. Which usually means tieing in straight up off the top of the boiler, limited horizontal run, and right back down to close to the bottom of the boiler. Plus using a normally open zone valve. That would allow for convection flow. And also using a break on rise aquastat that would also start the circ pump for an overheat when the power was on. (Which may mean moving the boiler circ to the bottom of the boiler, pulling thru both the protection valve & dump zone - to get the dump piping closer to the boiler at the top). I think an overheat is most likely to happen from an unexpected power outage causing pumps to stop pumping - followed by something like a sticking draft door or damper.

 

[warno]

My one concern on the storage to house line is the head number from that length of pex plus that load. The pump I have drawn in for that run is a variable speed with a set point option which I hoped would help with the return temps to my storage. I guess like you said I could always change things if it just completely didn't work.

My dump zone is simply for the event of an over heat situation. If there's a power outage there is a spring loaded damper that will shut. I was simply concerned about if my storage got up to temp and there's was still fire in the box with no loads calling for heat.

 

[maple1]

OK.

You'd likely be OK with your storage temps as long as you don't load up too much when they're getting close. It seems to take more fire to get it up that last few degrees than it does to get it up that first few degrees. Lots of this will be learn as you go, even after you think you're finally there. So to speak.

 

[warno]

So the drawing looks good as drawn?

 

[warno]

I have a new question now that I have the plumbing pretty well pinned down.

How close to a concrete floor can I put my tank bottoms for insulation proposes? I'm thinking my tanks will be pretty close to my floor in the area I have for them, so I'm just wondering how much room is ideal?