Froling Add-on Install

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The red numbers hand written match the cat numbers in the valve body and the instructions with the valve. The #1 port from TV2 goes to the suction side of C1 pump.

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Maybe the recirc line I plumbed at the outlet of C1 pump is confusing you? This acts as the cross the between the two headers.

This is a more accurate illustration on how I intend to plumb it.
Also recall thst my individual zones do not have zone valves and my pumps are on the cold return side of the zone pumping into the boiler inlet.
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The only thing I believe I should add is a valve in the recirc line to throttle the flow so it's not bypassing the zones.
 
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So close I can feel the heat. All copper is done with the exception of hanging the emergency gravity dump zone which is like two or three fittings and 2 ft of 1" tubing.

The two systems are connected and I'm back on the oil for now. Here's the last of the connections.

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I'm about to plumb my gravity dump zone but I have a question... I plan to install this horizontally, hanging from my floor joists and the far most end of the zone will be the highest (pitched for gravity). Do you agree that the incoming hot water should go to the top of the highest part of the zone before passing through the emitters? (Ignore the mess)
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I'm no expert on this but what you have there seems more complicated than it needs to be. At least to me. Think of what you are trying to do here. You want the boiler water to circulate by gravity and dissipate heat with the help of the fins. It must cool somewhat as it travels in order to return by gravity to complete the cycle.

I would eliminate that bypass pipe, hook the hot side to the low end of the fin tube and return to the boiler from the low end of the fin tube on the right.I would decouple the center fin tube from the fin tube on the left. That will give you one low friction loop which should do the job. Feeding the top may seem like the right thing to do since that would be the way to connect a water tank but in this case you don't have that reservoir of cold water on the bottom. I assume you're installing the NO valve on the hot side.

Hopefully someone with more experience will chime in.
 
Per the plans provided by TARM, the automog valve goes in the hot side of the zone so it will be moved accordingly. The valve open on loss of power.
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@Fred61, I don't quite understand what you are calling the bypass pipe. It's just three emitters plumbed in parallel.

This dump zone came assembled by the previous owner of the AST tank that I bought. It doesn't seem overly complicated to me. Hot water needs to travel from one end of the emitter to the other. I'm just wondering if the water should be traveling through the emitter as it travels to the highest part of the zone or on the down hill side... maybe it doesn't matter?

My idea was to mount it perpendicular to the joist over head.
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I'm not really sure but I'm not so sure it needs to have or should have slope to it? I'm thinking most of the drive would come from the verticals coming and going. If possible I would try to go straight up to it, and straight down from it, with what's in between being level. But not really sure. I would also like to see bigger piping on the ups and downs. Or I guess between the boiler and the two headers.
 
They call for 1" so that's what I used.
 
Hey Marshy,

1" is better than 3/4", as you are relying on gravity to do the circulation, so reducing the piping resistance is always a good thing. I too have my NO zone vale on the hot side. As maple1 correctly points out, you don't NEED slope to it, as gravity circulation will do the work. But you do need to think about how air will get out of that loop - remember there isn't a circ to temporarily jam on high to purge the air out of the loop. I shamelessly copied goosegunner's design you can see here. I have a 1" baseboard tee with a B+G #97 can vent on the hot side of the dump zone loop. And a purge valve as goose has as well.

I pitched all my piping so the high point is at the air vent and thus it self-purges. Hot on the left, cold on the right in this pic. 1" supply and return and standard slant/fin 3/4" BB. Hard to see, but my return is clamped to the underside of the superstrut, while the BB is on top. That should give you an idea of the pitch which I built into it. I piped reverse return as yours is as well.

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And technically speaking, the hottest water should be at the highest elevation - so as the water sheds heat on its way down the baseboard element, it's density increases and helps the circulation. If the baseboard element is hung flat, this should work. If you pitch it up, so the cooling water has to travel uphill by gravity circulation, well, as they say, your mileage will vary. FWIW, I've tested mine (never in anger) and it works the champ.
 
Hi Marshy, a little bit of upward pitch (hot coming into the low side) is desirable, but dead level would be OK too.

As you say, the pipes are plumbed in parallel. This will offer much less flow resistance than a series set up. This is important because the thermosiphon is a pretty gentle force and we want to make the flow path as easy as possible.

This does not look like a lot of radiation for a gravity dump zone. Be sure to test it once the install is finished.

looking good!

Chris
 
I think that dump zone is going into the scrap pile. The elements only have 1/2" tube and there is only about 18' of element on it. It shoukd have 20' and be 3/4 or 1". I'll salvage the 1" pipe off it and make the proper dump zone.
 
Where in NY are you? If not too far from me I could supply you with about 50 or more feet of fin tube for free, I have about 100 feet available but I have promised about 50 feet to another guy. I'm in Springfield which is on the Connecticut River.
 
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Where in NY are you? If not too far from me I could supply you with about 50 or more feet of fin tube for free, I have about 100 feet available but I have promised about 50 feet to another guy. I'm in Springfield which is on the Connecticut River.
I'm in central NY near Syracuse. I drive through Springfield every two weeks on my way to West Hartford. My next trip will be 3/16. Thanks for the offer, let me think it over. @nhtreehouse graciously offered a few feet of element also. I have plenty of wiring to do as well as put my tank liner in to keep me busy. I could push off the DZ and take advantage of your guys offers. I'll be in touch, thanks again.
 
Concerned that you may be thinking of the wrong Springfield. If you're going to Hartford you're probably taking the Mass Pike, the only highway that actually goes east and west in New England. You're probably going through Springfield Mass. Springfield Vermont is about an hour north on I-91. So it's a little out of the way for you.
 
Concerned that you may be thinking of the wrong Springfield. If you're going to Hartford you're probably taking the Mass Pike, the only highway that actually goes east and west in New England. You're probably going through Springfield Mass. Springfield Vermont is about an hour north on I-91. So it's a little out of the way for you.
Yes I was. Thanks for the clarification and for the offer but its too far.
 
Man, I can't believe how flimsy the junction box on these Grundfos pumps are. All plastic housing and cover is held on with onlay 2 screws.
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BLT controller is going in next to my Argo relay panel and right under my circulator.
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I have to agree on the grundfos connections. I was pretty disappointed to see that when my B&G pump has screw terminals.

Your system is coming together nicely. Keep up the good work.
 
I'll get there, hopefully before summer.
 
Might want to check your grunfos instructions but I believe you should turn the motor 90 degrees to the right.
 
Might want to check your grunfos instructions but I believe you should turn the motor 90 degrees to the right.
It meets the requirements. Shaft is horizontal and the terminal box conduit entry is facing down (and pumping I'm the correct direction!). Thanks for questioning it though.
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Tank sensors are in.
Lower:
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Upper:
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I'm trying to figure out where I should put the aqua stat for the BLT controller. This is the 4008A (opens on rise) to tell the controls the storage tank is too cold and to use the backup boiler. I was thinking I would place it at the same level as the upper sensor (to the boiler, right), about 4" from the top of the tank. That is about the same level at which the last upper coil for the heat exchanger is at (elevation wise). @Chris Hoskin, thoughts on placement?
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Well, the project is going to take another small delay. I ordered a new liner for my AST tank. I bought the tank system second hand and the previous owner let water sit in the tank for some amount of time resulting in the liner becoming stained green and black. It smells musty and moldy and I do not want to take a chance on the potential consequence of having it in my living space. I coulkd try cleaning it up but it's a large undertaking trying to clean and dry it. I spoke with Tom and got a new liner on order. He more material on order and it will be a week or more before he receives it.

I will take this time to finish the heat dump zone, wiring, sheet rock in the boiler room and some power wiring. Maybe come April I'll be burning. <>

I spoke with him about the sensor location and he advised I put them about 12" from the top. I'll move those lower and also get the lower sensor down too.
 
So close! Emergency heat dump is hung, just need a 1" 90 degree street elbow to finish the cold return. I'm down to two joints left to solder. Once I'm done with the torch the liner goes in and I start adding water to the tank. I feel like it's the home stretch. Just a few more wires to connect and i should be able to operate it.


Dump zone has 40' of emitters! Some came from the guy I bought the AST tank from, some came from @nhtreehouse, and I also bought 16'.
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