Purchase made - Froling S3 with dual 240 gal Storage

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Rear view with wall layer turned off.

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I been studying this drawing for hours to see if something can be improved. Question how are you regulating the flow to each zone valve or measuring flow. I still say your going to get reverse flow into the oil boiler when off, not that it matters that much.
 
I been studying this drawing for hours to see if something can be improved. Question how are you regulating the flow to each zone valve or measuring flow. I still say your going to get reverse flow into the oil boiler when off, not that it matters that much.
You would be much better off looking at this dwg. below.

To answer your questions, Im not really regulating flow to each zone valve at all, nor am i doing that in my current system but never had an issue.

Maybe if all zone valves opened at same time this may be an issue but honestly ive never seen that happen. I have LED's in each zone valve cover plate so i know when a zone valve is open when im in the boiler room but only once did i see 4 zones open. Most times its one or two.

As for the reverse flow through the oil boiler, can you explain how you are seeing this? Im not understanding how that can happen. There is a three way diverter valve on the cold water return to oil boiler. Based on wood boiler temps this valve will either direct water to oil boiler or back to wood boiler/storage. Am i missing something?
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If you have ghost flow to the oil boiler just drop in a zone valve. That needs to remain cold when not in use.
 
If you have ghost flow to the oil boiler just drop in a zone valve. That needs to remain cold when not in use.
As i stated, i dont see where im getting ghost flow to the oil boiler, the 3 way diverter valve prevents that....unless im missing something.
 
As i stated, i dont see where im getting ghost flow to the oil boiler, the 3 way diverter valve prevents that....unless im missing something.
It was just saying if you end up with ghost flow it’s easily stopped.
 
Ok you might not get flow but heat will conduct rather than flow into the boiler either from the tanks or from the boiler pump unit when running above its temp regupator and your other zones are not calling for heat. I wouldnt worry about it too much. Your air seperator should be closer to boiler but then when your oil boiler runs it won,t flow through the seperator. You would need another one for the oil boiler.
 
Ok you might not get flow but heat will conduct rather than flow into the boiler either from the tanks or from the boiler pump unit when running above its temp regupator and your other zones are not calling for heat. I wouldnt worry about it too much. Your air seperator should be closer to boiler but then when your oil boiler runs it won,t flow through the seperator. You would need another one for the oil boiler.
Actually thats what im hoping for as it will keep the oil boiler warm so when called for action it dont have to start from cold.

For the air separator, in actual linear ft its pretty close to both boilers but closer to the Froling. So you think i need one on the oil boiler as well?

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Im not an expert at this stuff, but maybe someone else can help with their input. However it looks like the dhw pump will get no air seperation effect if the oil is running or wood boiler running . Also you will be charging the tanks with no air seperator, based on the drawing.
 
Im not an expert at this stuff, but maybe someone else can help with their input. However it looks like the dhw pump will get no air seperation effect if the oil is running or wood boiler running . Also you will be charging the tanks with no air seperator, based on the drawing.
Ya i can see your point on the oil boiler for sure. Maybe i will add one there, cant hurt i guess.

The DHW tank and buffer tanks do have a auto vent installed on it from the factory, figured that would be sufficient.

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I just thought of something. If the wood runs out you will be heating the both tanks with oil. That sounds expensive, or am i incorrect?
 
I just thought of something. If the wood runs out you will be heating the both tanks with oil. That sounds expensive, or am i incorrect?
No, when the wood and buffer tank temp falls below the temp set in the Froling, the 3 way diverter valve will switch return flow through oil boiler only. It may appear that some ghost flow may still get through buffer tanks back through wood boiler but the 3 way Thermobloc cold water protection circulator on the Froling has a built in thermostatic valve which also closes off so no path there ether.
 
Im not an expert at this stuff, but maybe someone else can help with their input. However it looks like the dhw pump will get no air seperation effect if the oil is running or wood boiler running . Also you will be charging the tanks with no air seperator, based on the drawing.

I'm no expert either but dont think separation at each pump is needed. Just need some preferably at system high points that have a shot of horizontal to them long enough to promote said separation.
 
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I'm no expert either but dont think separation at each pump is needed. Just need some preferably at system high points that have a shot of horizontal to them long enough to promote said separation.
Yes that my understanding as well. Guess you cant have too many but these thing are pricy. I have to keep referring back to my old system where all i had was one air scoop and one auto vent and i never ever had an issue with air. Now with that said the new system will have alot more volume so understandably i should have at least one separation device, and from what i can tell the Caleffi Discal is a pretty good performer.
 
Yes that my understanding as well. Guess you cant have too many but these thing are pricy. I have to keep referring back to my old system where all i had was one air scoop and one auto vent and i never ever had an issue with air. Now with that said the new system will have alot more volume so understandably i should have at least one separation device, and from what i can tell the Caleffi Discal is a pretty good performer.

I think there is some of this stuff you don't have to be super strict with, doing what we're doing. One thing I didn't pay much attention to is the pumping away thing as applied to my boiler circ. I tied expansion in upstream of my load circ. Which is a ways away from my boiler circ. Then there are other subtle things that might end up playing a part later that you didn't anticipate. Like piping less restriction in the path between your load circ and storage than load circ and boiler, to prevent ghost flow through boiler when heating from storage. If one is just T'ing things together and not using 3 way valves.
 
I think there is some of this stuff you don't have to be super strict with, doing what we're doing. One thing I didn't pay much attention to is the pumping away thing as applied to my boiler circ. I tied expansion in upstream of my load circ. Which is a ways away from my boiler circ. Then there are other subtle things that might end up playing a part later that you didn't anticipate. Like piping less restriction in the path between your load circ and storage than load circ and boiler, to prevent ghost flow through boiler when heating from storage. If one is just T'ing things together and not using 3 way valves.
Yes i did read a fair bit on the pump away strategy and i think i have that covered as my expansion tank will be piped in pretty close to the suction side of the heating circ.

As for the ghost flow through boiler when heating from storage, I can kind of see some ghost flow there, how much i dont know. The path through storage should have less head (resistance) since the path through boiler will have to pass through the load circ and Caleffi quicksetter flow meter. To say there will be zero flow through there is unknow.
 
Buy them on ebay they are cheaper. I would put an extra one in really closer to wood boiler exit. Your spending 18 -20 k whats another $100:)
 
Hang on do you have enough clearance to clean the ash out from the bottom of the froling? It's the Long Rod with a Scraper on the end. If you needed to you could scooch the oil boiler forward enough to clear as an option.
 
Hang on do you have enough clearance to clean the ash out from the bottom of the froling? It's the Long Rod with a Scraper on the end. If you needed to you could scooch the oil boiler forward enough to clear as an option.
Yes just enough but I have an ash vacuum so likely will be using that anyway, lots of room for that. I think i measured that i will have 22" on the right side when looking at front of boiler. Good eye all the same.
 
How is the 3 way valve Froling/oil controlled? What are it's switching conditions.
Basically once the Froling and storage drop below programmed setpoints in the Froling software the 3 way valve will switch position and open return water flow through oil boiler. For switching back it will close path to oil once Froling reaches setpoint programmed but storage can still be below setpoint. At lease thats the way i understand it.

The software has many adjustable parameters and i dont even fully understand all functions yet. Once i get everything connected and the boiler is ready to be fired for first time the guys at Biothermic here in Canada will call and do a full over the phone commissioning procedure, so it will get sorted then.
 
You need to have a 3 way valve also of some sort or something to allow the load to be used 1st as the tanks are cold on start up, so the load gets priority.
 
On my system i have the feed to my HX before my tanks.It has a pump that pulls from the main feed to storage,runs through my HX then returns to the feed coming from the bottom of storage.
I works good,i can watch the temps on startup,it takes over 1/2 hour before any BTU's start getting stored,as the boiler comes up to temp and the near boiler pump stops the temps going to the load(house) keep rising till the house part of the system comes back up to temp,then you see excess BTU's start to accumulate in storage.Having the return from the HX go back to the boiler as apposed to storage helps a lot in keeping the boiler temps in the higher range.
When there is no fire a aquastat on the feed to the HX shuts off that pump to the HX and turns on my oil backup boiler.
 
You need to have a 3 way valve also of some sort or something to allow the load to be used 1st as the tanks are cold on start up, so the load gets priority.

Not a concern if your loads pull from top of storage. That's where the hot from the boiler will go as soon as it puts it out.