Integrating new Wood Boiler into existing system / layout

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Eastham Farms

Member
Nov 19, 2014
5
Central Virginia
I am trying to integrate my E250 Wood Gun with (2) insulated 325gallon horizontal propane tanks into my existing oil fired system with 200 gallons of storage. It consists of 3 hi temp zones (Cast iron Radiators) and 2 low temp radiant zones PEX loops in floors, 1 Water to air exchange for forced air. 1 water to water plate exchange for Hot Tub.

My question is this, How does one go about wiring and plumbing the system to bypass oil burner without flowing stored heated water through the oil burner when it is not running.

Secondly, i want the oil burner to come on at 130 degrees when the wood boiler is no longer able to produce heat but only charge the existing 200 gallons in the system loop, not the 650 gallons of additional storage.

Do i need 1 way valves ? can i bypass the boiler by using separate circulatory pumps for the wood boiler and the oil boiler. Basically using static water pressure to bypass the boiler. ?

My propane tanks have 1.5' plugs in the bottom, should i plumb into them or just use a dip tube from topside with a T on the bottom to introduce hot water to the bottom of the tank and draw my hot water off the top of the tank for my zones ?

Are there loop designs out there that members can post suggest.? I can make up a drawing of my current system and members might suggest modifications I would be needed to integrate.
 
I am trying to integrate my E250 Wood Gu
n with (2) insulated 325gallon horizontal propane tanks into my existing oil fired system with 200 gallons of storage. It consists of 3 hi temp zones (Cast iron Radiators) and 2 low temp radiant zones PEX loops in floors, 1 Water to air exchange for forced air. 1 water to water plate exchange for Hot Tub.

My question is this, How does one go about wiring and plumbing the system to bypass oil burner without flowing stored heated water through the oil burner when it is not running.

Secondly, i want the oil burner to come on at 130 degrees when the wood boiler is no longer able to produce heat but only charge the existing 200 gallons in the system loop, not the 650 gallons of additional storage.

Do i need 1 way valves ? can i bypass the boiler by using separate circulatory pumps for the wood boiler and the oil boiler. Basically using static water pressure to bypass the boiler. ?

My propane tanks have 1.5' plugs in the bottom, should i plumb into them or just use a dip tube from topside with a T on the bottom to introduce hot water to the bottom of the tank and draw my hot water off the top of the tank for my zones ?

Are there loop designs out there that members can post suggest.? I can make up a drawing of my current system and members might suggest modifications I would be needed to integrate.
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It depends on the size of your wallet. My old system simply balanced the temperature between the two boilers using a single circulator for the single heating loop and a second circulator used for the balancing of the water temperature using one Honeywell mechanical aquastat
for 33 years.

The more active controls you add the more complex your system will become and the harder it will be to diagnose any problems that occur

Flap check valves are not that expensive and will do the work you need if you simply pipe the tanks in series and then connect them to the heating load.

Heating the entire water volume in your system at one time will only help you not hamper your needs.

You can set the high limit at 160 and low limit at 140 and you will not burn that much fuel as you will have all the water circulating through your system and you will have plenty of hot water that will not take long to heat up as you will only need to heat the water once .


All you need to do is decide what your cut in and cut out temperatures are for the high limit control for the dump zone
 
https://www.hearth.com/talk/threads/primary-secondary-piping-for-boilers.11837/
This is a good thread to review.

Also the manufactures website, and manuals will give you basic designs. Also other manufactures will have other designs. EKO and Tarm have some.

The first step is to pick a plumbing scheme you understand (Primary/Secondary, Series, Parallel) and look at designs based on that scheme. I picked Primary Secondary with a pressurized boiler, and unpressurized storage, because it made sense to me, and it looked easy to add parts to the system later.

After you get your plumbing design down, add the controls on to that system.

Let us know what design you like and we can help you understand the details.