Continuous circulation help with indoor oil outdoor wood boilers

masonnewb

I recently installed a central boiler 760 hdx piped 1 inch thermopex 40 feet to 100 plate heat exchanger on the 1 inch copper return of system 2000 boiler. Heating 3800 sq/ft home and eventually 24000gal pool in spring and fall months. 2 of the 3 zones are forced air. 3rd zone was plumbed for baseboard which I recently finished (800 sq/ft Bonus room above a 3 door garage).  Dhw heated with existing plate exchanger that came with system 2000. Circulator runs continuously on owb and have since set up indoor boiler to do the same. My question is should I be running the circulator continuously on my indoor oil boiler? I assumed I needed to in order to exhaust the heat from the plate exchange but am unsure if this is necessary.  Problem being the zone valves for the 3 zones. Where does the water go if the circulator is running continuously and all zone valves are closed? I do not know much about heating but have spent the last few weeks  researching as much as I could find. Have not found anything about circulator running continuously with zone valves installed in the system. And do I need to run circulator continuously on indoor oil boiler and if so would it be logical to set up dump zone in the garage?  I have the installation diagram from system 2000 for operation with out door wood boiler but will be a few day project and will have to wait till spring. In the mean time... thanks in advance

hot_rod

A sketch of the piping migh help see what you have. No the circ cannot run against closed zone valves

EdTheHeaterMan

You need to run the System 2000 circulator (what we will call the system circulator) in order to use up the heat from the wood stove. You can do this with a control set up that will open the zone valves when ever there is heat being generated by the wood stove. Now you will find that the house will get hotter that the thermostat settings, but that will need to be controlled by the way you fire the wood stove. If the house is too hot, then use less wood.

NO do not run any circulator with closed valves. Make at least one stay open manually for now.

What size storage tank does your system 2000 use for domestic hot water storage? Can you show us which piping diagram in the I/O manual is most like your piping design? Then maybe where you added the OWS Heat exchanger to that piping?

masonnewb

40 gal hot water tank. 

masonnewb

Ideally I would use 2nd zone as dump as duct for forced air is in the attic but for some unknown reason the fan only works when set to on and not auto. 

EdTheHeaterMan

masonnewb said:

Ideally I would use 2nd zone as dump as duct for forced air is in the attic but for some unknown reason the fan only works when set to on and not auto. 

We can fix that with controls too. I like to draw wiring diagrams, The Wallies will sometimes tell newbies to ask me to help that way.

My former home is Hydronic coils in air handlers, and I have a great wiring/control design so you don't blow cold air.

masonnewb

masonnewb

Most similar to this but does not go to supply. Goes back to return as I did not want to bypass any existing safety features equipped on oil burner

masonnewb

Thank you Ed. I've checked the wiring maybe about a year ago on the thermostat (which I beleive is relatively new) and recently tried my best to check wiring at oil boiler as well and looks ok. Have not checked wiring inside duct

EdTheHeaterMan

masonnewb said:

Thank you Ed. I've checked the wiring maybe about a year ago on the thermostat (which I beleive is realively new) and recently tried my best to check wiring at oil boiler as well and looks ok. Have not checked wiring inside duct

Did the air handler blower operate automatically in the past? or has it been this way all along?

masonnewb

That I do not know. The wife beleives it happened several years ago when someone came to service something or other. I will try and see if i can find out more. I did see the other forced air zone thermostat wire has the green and red wire in same terminal whereas the zone that does not function properly does not have the ground connected just the red and white. Not sure if that is anything but didn't want to mess with it

masonnewb

The wife says fan auto works with the air conditioning though. 

masonnewb

I guess green is not ground but for the fan.. whoops. Going down now to connect and will let you know

masonnewb

Connected green at oil boiler with no success.  

leonz

My hand fed wood boiler was set up to use 2 circulators using one as a temperature balancing circulator between the two boilers leaving the other one to provide circulation to my 225+- feet of fin tube baseboard.

As you have a forest eater I am going to make one big suggestion that will save you a great deal of work and cut your wood use.

Purchase a piece of 2-inch by 26 inch long by 18 inches wide channel iron wide to fit in your fire box ; you could use two 2" by 8 inch by 26 inch long pieces of channel iron by placing the channel iron on the air tubes with the flat side up and fill your firebox half full right up to the flue breech with standard firebrick that will create a huge heat sink for you and also cut your wood use in half. The wood you use will also burn hotter as the fire brick is releasing heat at the same time the fire is dying back down and continuing to heat the water.

masonnewb

Thank you ieonz. Do you have a picture to help me better understand what you are talking about?

GroundUp

A wraparound circ through the HX and the oil boiler running 24/7 is not uncommon, but it's not the same circ that serves your heating zones

hot_rod

It seems like an odd piping. Isn’t the. “Wrap around” and system pump in series?  So how do you turn off the heat if the wrap pump is continuous?
Also you lose a % of heat when circulating through that un fired boiler.

And does the existing boiler flow through the wood boiler when it is running? Via the HX

Or does the outdoor boiler pump shut off when the gas or oil boiler runs?

masonnewb

Thank you hot rod. It is a temporary set up as it was December when my wood boiler came in. Thermo pex still above ground and alot to do in the spring. Don't plan on firing the oiler boiler. I'm aware now that the circulator I put in isn't needed where it is but hope it's not an issue for the next couple months. But yes the existing boiler would keep wood boiler hot if I keep it like this. Wrap around pump should go to supply somewhere... 1 site says to tie it in at pressure releif with aquastat to keep boiler up to temp. As for oil boiler heating the wood boiler i was thinking of putting a t in and some bypasses but at this point going to fix all according to ek1 diagram for system 2000 in spring after thermopex is buried. I have zone valves opened manually on forced air zones so hot water cycles through air exchangers. Fixed fan auto on 2nd zone so thats a releif. Again not ideal but temporary. I work for a tree service and have unlimited supply of wood so with the price of oil thought it made sense.