Right place for 2nd expansion tank

[Brian Murray]

I just installed a Budarus boiler and changed to circulators from zone valves. Now adding a wood boiler into the system. I need a second tank and want to know if this is a good place to add it, I have tees into the return side. I am not sure how the Tees play into the pressure. The pipes are 1 1/4 i drew a crude photo and added it The wood boiler hold 30 gallons,

I can also add the pump up to just after the tank so the tank is on suction side of the pump

 

[Fitter30]

Ex tank needs to be on the suction side of the wood boiler. Ex tanks only work on the suction side of pumps and air pressure the same as system pressure of a water temp 100* are less with pumps off. Normally 12 lbs.

 

[Sponsor]

 

[Brian Murray]

Fitter are you saying two tanks are ok on a primary secondary loops.

 

[Fitter30]

After looking into wood boilers there water side isn't rated for pressure they are a vented tank.. Also antifreeze would have to be added for freeze protection. A heat exchanger would be necessary to separate the systems.

 

[Brian Murray]

The wood boiler I am installing is a pressurized system It will be tied into the same as my oil burner

 

[Fitter30]

Still want glycol for freeze protection? How many gallons of water does the wood boiler hold?

 

[Brian Murray]

30 gallons, Its is in my basement as an add on its a Royall 6150

 

[Fitter30]

Just eliminate the heat exchanger pipe wood boiler with back to back tees pump on leaving water.

 

[Bgard]

System only needs one expansion tank, just increase the size of existing one to handle the extra volume of water in the wood boiler. The pump on the wood boiler should only run when there is a fire burning, if it runs all the time the unfired wood boiler becomes a radiator .