Linking wood boiler to propane

[maplewoodshelby]

I have read thru many of the posts on piping but still confused. I currently have a propane boiler and will be installing a wood boiler (which will be my primary heat). I do not have storage. There are two zones in the house. Upstairs and downstairs.
I hear two different versions on piping these boilers. One says that I shoudl not pipe them together (run water from wood boiler thru the inactive propane furnace. Others have said just pipe them together and use valves as stated below from the manufacturer of my stove. I have tried to put the picture diagram from the manufacturere on here with no luck. This is the link if you have time please look at it and tell me what you think
(broken link removed to http://www.energyking.com/hot-water-furnace-specs.htm) and then click on the PDF manual and the diagram is about halfway thru the document

Basically this setup runs the heated water from the wood boiler thru the propane boiler to the house and back to the wood boiler. If not using wood boiler then close valve and it is isolated from the propane boiler which is running the heat. Any problems with this


When plumbing into your existing heating system,
RJM Manufacturing, Inc. recommends installing a
series of three gate valves. The three gate valves are
to be used in the event you do not use your ENERGY
KING Wood/Coal Boiler for an extended period (one or
more weeks).
When the ENERGY KING Wood/Coal Boiler is in use,
Valves #1 and #2 are open and Valve #3 is closed.
To isolate your ENERGY KING Wood/Coal Boiler from
the heating system when the ENERGY KING
Wood/Coal Boiler is not in use, close Valves #1 and #2
and open Valve #3.

 

[timberr]

Hey Couchburner,

I installed a Eko 25 and a Munchkin Contender propane boiler for backup. I am running a primary/secondary setup. On my secondary loop I have a supply and return coming from starage (wood heat) and a supply and return coming from the Munchkin. When there is a call for heat two sensors' are energized that look at the temp of my storage. Based on the set points of the sensors either the Circ from storage is energized or the Munchkin is energized. No playing with valves, right now it is too hot for wood so I am using the Munchkin for DHW.

Good luck

 

[Eric Johnson]

You can do it either way. Piping them parallel is more efficient and easier to control, but putting them in series is cheaper and easier and in some installations (like mine) the logical way to do it, given what I had to work with. You should always try to pipe it so that you can isolate each boiler and run it without sharing any water with the other boiler, in case one of them springs a leak or you have to do some other maintenance.

There's about a million ways to pipe these things. It's probably usually best to go with the mfg. recommendations--if they make sense, which is not always the case.