Replacing old expansion tank

jgaudet

@epmiller ya it's probably best to wait till the spring to start doing major repairs, Yes that is a odd branch on that side it's the one with my dump zone. There is a lot I want to do to this system when it warms up outside. And thanks that's the order I will bleed it when I do it! 

@EdTheHeaterMan I just tested your theory today and yes my oil boiler is still hot when my wood boiler is operational. So in the spring I will be trying to set up my system the way you were telling me! 

jgaudet

@EdTheHeaterMan I'm wondering if maybe the reason my oil boiler is still hot when my wood boiler is operational is because my domestic hot water comes through my oil boiler?  And also when I'm using my oil boiler the circ only comes on when a zone calls for heat but I noticed when im using my wood boiler that circ is on all the time even when a zone is not calling for heat is that normal?

EdTheHeaterMan

I did not realize you get your Domestic Hot Water (DHW) from your oil boiler. A closer look at this section (circled in red) does show what might be the Hot and Cold water pipes and a mixing valve (necessary for the safe operation of a tankless coil). Some of the pipes are blocked by other pipes, and this angle of the oil boiler does not show you have a tankless coil.


The design logic of the control system is correct for your application. Also, Primary-Secondary piping is not necessary in your case because the tankless DHW coil must stay in a heated boiler. It should be heated by the wood burner when possible and oil should come on when the wood burner can not keep up. So the redesign may not be necessary. I believe your design is correct. The only thing I would change (in the spring) is the expansion tank location and the circulator location so the "System" circulator is used to heat the baseboards... pumping away from the expansion tank.



The woodstove circulator can stay on the return of the wood boiler to put heat in the oil boiler whenever the wood boiler has heat available.

EdTheHeaterMan

You might want to keep this, in the event you want to have a more efficient DHW system. Using an indirect tank can save you in the long run.

Just a quick question about your wood boiler. Is there any automatic control that can regulate the combustion-air dampers based on water temperature on your system? If you could keep the temperature hovering between 165°F and say 185°F, your burn may last longer, since the boiler won't overheat as much.

jgaudet

@EdTheHeaterMan thanks for the great information, yes where that circle is that's the hot and cold lines with a mixing valve.  So basically i just need to change the location of my expansion tank and the circulator beside my oil boiler to the supply line and size the expansion tank properly for my system so I can eliminate the old expansion tank beside the wood boiler?  

And yes I do have an auquastat that I can change the settings on the wood boiler

My wood boiler is set at hi-200, low-180 and limit control for circ 150

And on my oil boiler the triple aquastat is hi-170, lo-150 with differential at 15

EdTheHeaterMan

You have it nailed. Wait until the spring or summer when you don't need heat. Get a #60 tank for the one location, but save the #30. If the 60 is not enough (because the wood boiler may contain more water than a regular boiler) you can install a Tee fitting at the expansion tank and add the # 30 to the system. You will have the equivalent of a #90 then.

jgaudet

@EdTheHeaterMan ok perfect. Thanks for all the great help!  Also just one more thing right now my automatic water feed goes into my boiler drain, when I get my new tank should I make the water feed go into the expansion tank instead?  And I will have expansion tank then air eliminator then circulator in that order on the supply line right?

mattmia2

the expansion tank and air eliminator should between the outlet of the boiler and the circulator so the air eliminator is at the point of the hottest water and lowest pressure where air will be least soluble in water. The tank should be on the suction side of the circulator so that the pump is pushing water out in to the system instead of in to the expansion tank. Where the prv connects doesn't matter a whole lot.

jgaudet

@mattmia2 ok perfect can't wait till it warms up outside so I can do an overhaul on my system!  Thanks 

jgaudet

just wondering when i do my overhaul on my system can i leave my zone valves on the return line and then have my expansion tank, air eliminator and circulator on the supply line or should my zone valves also be on the supply line?

EdTheHeaterMan

@jgaudet I agree with this assessment, except the PRV is best located at the expansion tank. this ensures the Expansion tank and the PRV talk the same language. The language of water pressure

As far as the Zone Valve location. They are fine as is. No need to change the ZV location I might make a minor change to the supply manifold. Use 1-1/4" from the boiler outlet thru a 1-1/4" air separator to a 1-1/4" shared pipe (manifold). From that 1-1/4" shared pipe, take each 3/4" branch directly off the 1-1/4" shared pipe. If you notice the small change I made in the supply manifold drawing I added to the most recent diagram

mattmia2 said:

the expansion tank and air eliminator should between the outlet of the boiler and the circulator so the air eliminator is at the point of the hottest water and lowest pressure where air will be least soluble in water. The tank should be on the suction side of the circulator so that the pump is pushing water out in to the system instead of in to the expansion tank. Where the prv connects doesn't matter a whole lot.

This illustration shows a common mistake that often has no consequence. In some isolated cases though it can be an irritating, unsolvable problem... unless you think like water.
If you acknowledge that the expansion tank is the point of no pressure change, and give that tank a charge of 12 PSI air cushion. As the water heats up and expands the water expands into the tank with a minimal increase in air/water pressure in the system. As the water cools, air pressure pushes the water from the tank back into the system.

If we can all agree to that concept we can then look at the way a pump may affect the water/air pressure dynamic.
Notice three pressure gauges on the system. If there is no pump operation the three pressures will all be the same.

Now if the PRV is set at 12 PSI then the expansion tank will develop 12 PSI air pressure. When you turn on the pump, the gauge near the expansion tank will not change. (because it is the Point of no Pressure Change) The gauge on the discharge of the pump will increase slightly to compensate for the pressure drop thru the boiler and piping between the expansion tank and the circulator. So that gauge might read 12.5 PSI

Now, what happens on the inlet side of the pump? If the outlet side is 12.5 PSI and the inlet must be lower than the outlet then the inlet side of the pump MUST drop below the 12 PSI of the system at rest. If the pump developed a pressure difference of 6 PSI then the inlet of the pump is now 6.5 PSI (which is 6 PSI lower than the outlet) ... Wait a minute ... the PRV is now connected to a pipe with only 6.6 PSI. If I was a PRV set at 12 PSI looking at a pipe with 6.5 PSI in it, What would I do? Maybe I would add enough water to get the pipe to 12 PSI.

Now I have added a few quarts or gallons of water to the system. Let's see what happens to the rest of the system. The pump inlet is now 12 PSI, so the outlet is now 18 PSI. After a pressure drop of 0.5 PSI, the pressure at the expansion tank is now 17.5 PSI. Since the relief valve on the boiler is set to release at 30 PSI, the 17.5 new operating pressure is not an issue. As the temperature increases, the pressure may increase to 22 or 25 PSI... still not a problem. And life is good in the world of never experiencing the unknown problem in this design.

But, if you have a 4 or 5 story building and your PRV might need to be set at 15 or 18 PSI... And if you have a larger system you may need to use a more powerful pump... Now you will be starting at 18 PSI cold at rest. Then add 9 PSI to the pump pressure difference... and the numbers now get very close to 27 PSI after you start the pump. Add some heat to that water and the expansion will cause the pressure relief valve to release on a regular basis.

So the PRV, Expansion tank, and the inlet of the pump SHOULD always be at the same location on the piping system.

Respectfully submitted,
Mr.Ed

jgaudet

@EdTheHeaterMan thanks, that was my plan to use an amtrol filtrol expansion tank with my water feed going into that! Just wanted to make sure I was ok to leave just my zone valves on the return line all by themselves!

EdTheHeaterMan

I'm not a fan of the FIL-TROL system. It is a great concept however there will be a time when you will need to replace the expansion tank. That is when you will experience a comedy of errors leading to the replacement of the FIL-TROL valve and tank combination with a conventional PRV and standard tank. The FIL-TROL tank does not have the same thread as the standard Extrol tank. The Extrol tank does not have a dimple at the top of the bladder to activate the FIL-TROL valve. The FIL-TROL replacement may be a special order part when you need it so you will opt for changing out the whole thing.

Here is an illustration I used to show the proper piping of a Fill Valve System used in a Pumping Away design.

Notice the ball valve for service on the inlet just before the system and the ball valve just before the backflow preventer. These two ball valves make replacing the components between them easily without the need to shut off the entire house's water supply or draining the boiler.

The only change I might make is to place the ball valve between the expansion tank and the air eliminator. This way you can also replace the expansion tank without draining the entire system.

jgaudet

@EdTheHeaterMan what's Im?

EdTheHeaterMan

jgaudet said:

@EdTheHeaterMan what's Im?

refresh for the complete comment.

jgaudet

@EdTheHeaterMan I did not know that about the filtrol and and I like the illustration! Makes more sense now and I will just go with the extrol tank and a prv and pipe it like the illustration. Thank you 

EdTheHeaterMan

This design will actually make purging the baseboards much easier. By placing a full port ball or gate valve (A) on the supply riser just after a boiler drain (B) or hose bib, the entire purge can be completed with isolation valves from that single hose (C) connection.

By keeping valves 1,2,&3 closed you can charge the system piping with house water pressure because the boiler is isolated by valves on both the supply and the return.

Connect the garden hose (C) to the hose bib (B) and open the hose bib. When you open the first baseboard loop Isolation valve on the return, the 40+ PSI will push all the air from that loop of baseboard.


Once you complete that (water flowing with no air from the hose) shut off zone 1 isolation valve and let the pressure build back to the house water pressure.


Then open zone 2 Isolation valve. Once there are no more air bubbles from the hose move on to the next... and so on until all the zone loops are air-free.

Then place the fast-fill back to automatic position. Open all the isolation valves and Purge a little more water from the boiler hose bib to reduce the pressure to normal cold start pressure (usually 12 PSI) and then close the purge hose bib and remove the hose. Finally open the main supply valve (A) in order to allow water to flow properly. (Don't and how many times I forgot to do that)

Since you are going to repipe the supply-side anyway, you may as well make things easy for yourself.

Let us know how it works out in the Spring. and send pictures.

Yours Truly,
Mr.Ed

jgaudet

And just one more thing is the piping like this coming from my wood boiler going to be fine where they connect to the oil boiler?  And the only thing I will have on those lines is the second circulator in my system on the return pipe going into the wood boiler to keep the water circulating between the 2 boilers 

jgaudet

@epmiller I decided to try the bucket method today to see if I could get the rest of the air out of one of my zones and I hooked it up how you said but it seems like it was putting more water into the bucket than it was putting back into the system so I had to stop to empty some of the bucket and it seems like it may have just put more air into that zone lol

epmiller

@jgaudet I hope you shut off the feed water to the system before you tried that. That will happen if you forgot that detail. That can also happen if your expansion tank is pushing extra water back into the system that is now at lower pressure. The expansion tank should be isolated before purging zones.

jgaudet

I didn't have the water feed shut off but it wasn't trying to add any water through it while I was purging,  but I didn't have the expansion tank isolated!  Also the 1 inch pipe that goes from the return line on my oil boiler to my wood boiler I always hear air in that line, by purging my zone valves that will not help that line right. If not is there a way I can get the air out of that line?

jgaudet

@EdTheHeaterMan I'm finally doing my system over before the cold weather! And I just had a couple quick questions.  So during the summer I had a marathon electric hot water heater installed for my domestic hot water so I will only be using my wood and oil for my heat. So do you think I should go with the primary secondary piping? And if so will it work the same way if my wood boiler drops below set temp my oil will take over? And also the way it's set up now you say it's wasted heat with the wood boiler heating the oil boiler to but does that not act as a storage tank and give me more hot water to use for my heat?  Thanks

EdTheHeaterMan

You are correct, the oil boiler will act as additional buffer for when the woodstove is operating. I would be concerned with the fuel oil being wasted on heating the wood boiler. That will probably the largest radiator on the oil boiler system and it is connected to a chimney, so that radiator will be literally heating the outdoors thru a very expensive vent pipe. ...so I would pipe the boilers as separate secondary loops with separate circulators If the expansion tank is on the radiation loop, that is the primary loop.

The wiring can still be set up to operate the oil boiler when the woodstove is insufficient to heat the space.

jgaudet

Ok thanks. I think I like the idea of having the oil boiler as additional buffer for when the wood boiler is going. And I won't have to use much oil maybe like an hour a night. So I think I'll just change my main circulator location to the supply line like this picture you had for me before!  Also one more thing if I'm not using my coil for domestic should it or can it be taken out of my boiler or just leave it alone?  Thanks again

leonz

The first thing you need to do is shut off the autofill valve
The second thing you need to do is shut all the automatic air vents and leave them shut.
The third thing you need to do is shut the valve off for the bladder tank
The fourth thing you need to do is drain the excess water out of the steel compression tank by opening the drain valve.
The fifth thing you need to do is turn the heat up and then you can get rid of the air bubbles in the system using the blue handled boiler drain valve and a garden hose to purge the air will help the system a great deal by purging the air bubbles out of the heating loops.
The sixth thing you should do is put all the swear words for the plumber that made that mess in a swear jar and put the cap on and send it to him.

If you shut off the vents and close off the bladder tank you can purge the air in the system by opening the drain in the base of the steel compression tank as long as you keep the water circulating.

If you invest in a new steel compression tank, sight glass, airtrol valve and plumb in an Internal Air Separator the size of your close boiler plumbing before the heating season starts exactly where your existing steel compression tank is now you will have many fewer problems, buy the books below and you will see everything much more clearly.

The drawing that edtheheaterman has provided you will work very well for your system as long as you eliminate the automatic air vents/close them and close off the bladder tank since they are already there.
Whoever installed the oil boiler complicated things as it eliminated the point of no pressure change by installing the bladder tank and air vents.

To make your heating system perform flawlessly you should replace the existing steel compression tank with a new one of equivalent size and install an airtrol valve in the bottom the new tank along with a sight glass gauge, Internal air separator and airtrol valve so you know how much water is in the system and it is easier to maintain.

Your making your heating system more difficult to deal with than you need to by wanting to do what you are contemplating as the same size replacement steel compression tank will have more air volume and it will let you operate at lower pressure as you will have 10 plus gallons of water in the expansion tank to regulate the system pressure.

You should purchase two of Dans books to solve this issue which are PUMPING AWAY and CLASSIC HYDRONICS to fix the mess your plumber created.


My thoughts anyway.

STEVEusaPA

A lot to examine here...

leonz said:

If you shut off the vents and close off the bladder tank you can purge the air in the system as long as you keep the water circulating...

WRONG. You don't purge the system of air with the circulator running, NOR do you need to close the bladder tank

leonz said:

If you invest in a steel compression tank, sight glass, airtrol valve and plumb in an Internal Air Separator the size of your close boiler plumbing before the heating season starts exactly where your existing steel compression tank is now you will have many fewer problems, buy the books below and you will see everything much more clearly.

I know you love the steel tank, but the bladder tank will work fine, piped correctly and properly charged

leonz said:

The drawing that edtheheaterman has provided you will work very well for your system as long as you eliminate the automatic air vents/close them and close off the bladder tank since they are already there.
Whoever installed the oil boiler complicated things as it eliminated the point of no pressure change by installing the bladder tank and air vents.

What?

leonz said:

To make your heating system perform flawlessly you could replace the existing steel compression tank with a new one of equivalent size and install an airtrol valve in the bottom the new tank along with a sight glass gauge so you know how much water is in the system.

Flawlessly is incorrect. It will still require attention and draining/recharging steel compression tanks takes much more work than checking and replacing a bladder tank, installed with a Webstone expansion tank valve.

leonz said:

Your making your heating system more difficult to deal with than you need to by wanting to do what you are contemplating as the same size replacement steel compression tank will have more air volume and it will let you operate at lower pressure as you will have 10 plus gallons of water in the expansion tank to regulate the system pressure.

leonz said:

You should purchase two of Dans books to solve this issue which are PUMPING AWAY and CLASSIC HYDRONICS to fix the mess your plumber created.

The only thing with which I agree.

leonz

STEVEusaPA said:

A lot to examine here...

leonz said:

If you shut off the vents and close off the bladder tank you can purge the air in the system as long as you keep the water circulating...

WRONG. You don't purge the system of air with the circulator running, NOR do you need to close the bladder tank
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I never had one issue with purging with the circulator running as the minute I opened the vent it pushed the air out of the highest piping eliminating the air lock.
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leonz said:

If you invest in a steel compression tank, sight glass, airtrol valve and plumb in an Internal Air Separator the size of your close boiler plumbing before the heating season starts exactly where your existing steel compression tank is now you will have many fewer problems, buy the books below and you will see everything much more clearly.

I know you love the steel tank, but the bladder tank will work fine, piped correctly and properly charged

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The plumber that installed the new boiler and new plumbing had no business doing it the way it was done period. They should have used one circulator wired to run continuously to balance the temperature between the two boilers.

They should have used a pair of Internal air separator for both boilers to feed any air bubbles to both steel compression tanks using a common single feeder pipe and employed airtrol valves at the base of both tanks to allow venting of excess water
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leonz said:

The drawing that edtheheaterman has provided you will work very well for your system as long as you eliminate the automatic air vents/close them and close off the bladder tank since they are already there.
Whoever installed the oil boiler complicated things as it eliminated the point of no pressure change by installing the bladder tank and air vents.

What?

leonz said:

To make your heating system perform flawlessly you could replace the existing steel compression tank with a new one of equivalent size and install an airtrol valve in the bottom the new tank along with a sight glass gauge so you know how much water is in the system.

Flawlessly is incorrect. It will still require attention and draining/recharging steel compression tanks takes much more work than checking and replacing a bladder tank, installed with a Webstone expansion tank valve.
==========================================================

My system with a single 225 foot heating loop works fine and doe not require draining as the water feed valve is shut off and the system pressure is correct.

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

leonz said:

Your making your heating system more difficult to deal with than you need to by wanting to do what you are contemplating as the same size replacement steel compression tank will have more air volume and it will let you operate at lower pressure as you will have 10 plus gallons of water in the expansion tank to regulate the system pressure.

leonz said:

You should purchase two of Dans books to solve this issue which are PUMPING AWAY and CLASSIC HYDRONICS to fix the mess your plumber created.

The only thing with which I agree.

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the plumber he hired only made it worse.

jgaudet

Ok thanks for the comments.. I'm just wondering is it gonna be ok if I do it the same as this picture or if I should change anything? 
I just want to have one expansion tank and put my main circulating pump on the supply line!  So do you guys recommend me using a steel compression tank and remove all air removing devices or should I put a diaphragm tank?

leonz

Plumbing the system as edtheheaterman suggests will be fine. Close all the automatic air vents and shut off the bladder tank.
You need to upgrade the steel compression tank with an airtrol valve to let the hot water and microbubbles enter the steel compression tank to let them dissolve in the air space above the water volume in the tank. The cooler water will sink back into the line and go back into the heating loop of system.
If you plumb in an Internal Air Separator (IAS) in the line coming out of the oil boiler and then use the top tapping of the IAS for the line going to the compression tank following the installation instructions exactly the air bubbles will rise into the steel compression tank more easily.

jgaudet

Ok perfect I forgot to add the picture in my comment but here is the one I was talking about! And also there is an automatic air vent on the top of my oil boiler should that one be closed also? 

leonz

jgaudet said:

Ok perfect I forgot to add the picture in my comment but here is the one I was talking about! And also there is an automatic air vent on the top of my oil boiler should that one be closed also? 

If the blue scribble is the vent YES it needs to be shut off if you intend to use the steel compression tank.

jgaudet

I decided I'm not going to do primary secondary incase something happens to my electric hot water heater then I'll have my boiler for my domestic.. so all I am going to do is change my primary pump that is on the return line beside my oil boiler to the supply line and remove my expansion tank from my garage and just use 1 bigger diaphragm beside the primary circulator beside my oil boiler like the pic.. but I had my plumber guy here today just to check things out and he told me on my system I need 2 expansion tanks 1 beside my wood boiler and one beside my oil boiler is this correct?  Also he thinks I shouldn't use a diaphragm tank with wood boiler.

leonz

jgaudet said:

I decided I'm not going to do primary secondary incase something happens to my electric hot water heater then I'll have my boiler for my domestic.. so all I am going to do is change my primary pump that is on the return line beside my oil boiler to the supply line and remove my expansion tank from my garage and just use 1 bigger diaphragm beside the primary circulator beside my oil boiler like the pic.. but I had my plumber guy here today just to check things out and he told me on my system I need 2 expansion tanks 1 beside my wood boiler and one beside my oil boiler is this correct?  Also he thinks I shouldn't use a diaphragm tank with wood boiler.

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Sent you a PM

jgaudet

@EdTheHeaterMan im in the process of doing what you told me in this picture. i have removed my old steel expansion tank beside my wood boiler and i decided to remove the air vent by the ceiling. i have a #90 - 14 gallon diaphram tank im installing where you said in the picture along with a webstone expansion tank valve and a spirovent jr air eliminator. also im going to add the 3rd circulator where it say future and make that my main cirulator! now my only question is is the piping ok like it is or should something else be changed because also took my domestic hot water coil out of my oil boiler so im just not sure how to hook it together with the wood boiler to be primary secondary? im not in a big rush im just taking my time because i got heat pumps for now incase it gets cold out! but if you wouldn't mind maybe helping me rearrange the drawing again for primary secondary that would be really appreciated! thanks

psb75

Wood boilers and other solid fuel burners work best when heating appropriately-sized heat-storage (storage volume matching the max BTU output of wood-boiler). Wood boiler should always be burning "full-tilt boogey" to be really efficient. Load the boiler and burn up the fuel load in one session--with all BTUs going to storage. The house radiation should then draw from storage (and boiler when burning). The plumbing should be set up "primary secondary" with the storage as a secondary source like the oil boiler-- having its own circulator. A hydraulic separator would be ideal. This way no boiler ever heats the other one. AND the wood boiler heats really efficiently. The oil boiler does not need to heat storage-- only the house as a back-up to the heat storage tank and wood boiler.

jgaudet

@psb75 so your saying I can use my oil boiler as a storage tank after my wood boiler heats the water without loosing any of the heat up the stack? 

EdTheHeaterMan

If you are going to do a major repipe, or a minor repipe in the boiler room. This is what you would be looking to accomplish. By placing the wood stove boiler furthest from the primary circulator, the oil boiler can act as a buffer tank (as suggested by others) by operating the oil boiler circulator simultaneously with wood stove circulator. If you decide to add a buffer tank it can also be added between the wood boiler and the primary circulator. When the woodstove is generating temperature above a minimum setting (perhaps 130°) all the circulators will operate. This will allow for the wood boiler to add the maximum amount of heat the the entire system. In this case, the oil boiler will act as the buffer/storage of excess heat that may be generated by the woodstove.

when the woodstove no longer has any heat, the oil boiler will be allowed to operate and only Circulator A and C will move heated water. In this way, no additional oil will be wasted heating the woodstove.

The control wiring/logic will need to be addressed in a way that will provide proper circulator operation in order for the most efficient use of the oil burner.

Final edit:
In the event all the zone valves are closed, and the woodstove is still providing heat to the system, a bypass (indicated by the dotted line) should be included in the boiler room piping redesign. Adding the Flow Control Valve will allow for flow to the buffer tank(s) when all zones are closed.

jgaudet

@EdTheHeaterMan

Thank you very much that is exactly how I want it when I'm done and that's helpful information for me! I'm glad you mentioned the bypass because I wasn't thinking of that! And the only thing I won't be adding the optional buffer tank but everything else will stay the same right? And my piping coming off both boilers is 1 inch. how far spaced will they need to be?  And just one more thing when I purchase my 3rd circulator "A" should it be the same size and brand as the 2 I have now?

EdTheHeaterMan

Pipe sizing has a lot to do with BTU capacity. Here is a text that you may find helpful in determining the proper size pipe for each section of the system. http://media.blueridgecompany.com/documents/ZoningMadeEasy.pdf

Page 4 and 5 will help you in selecting the proper pipe sizing to move the proper amount of water based on BTU capacity. Page 8 offers you a way to determine what pump will work best for each section of the system.

So, I am unable to tell you that one inch pipe is large enough. I can not select the proper pump without knowing more about each section of the system. Wood Boiler BTU output, Oil boiler output, BTU capacity of each zone of radiator output. Also the one section of pipe on the original drawing where there are two 3/4" zones piped off of one 3/4" branch may be a cause for concern.

EdTheHeaterMan

After you read Zoning Made Easy, you will understand that 1" pipe will move about 80,000 BTU capacity. Look at the BTU capacity of the boilers. If the wood stove will generate more than 80,000 BTU, then you might want to consider 1-1/4" piping from the boiler room to the woodstove. Also the primary loop (that is where the expansion tank is) may need to be 1-1/4" or 1-1/2" copper or iron pipe size. Take the time to read the entire booklet. It will answer many of the questions you have.

The existing circulators may also be the correct size for the Primary Loop circulator. You will be able to determine that, once you know the capacity of all the connected radiation. Unless your home is very large, and you have maxed out each 3/4" loop of baseboard to the 40,000 BTU capacity of the 3/4" pipe (by having over 65 feet of element on each of the 4 loops) then you will probably be fine with you circulator choice.

I hope this helps

Yours Truly,
Mr. Ed