Indirect Tank Plans - Check My Plans

SandysEn

Hello I'm looking to add an indirect tank. Should the boiler supply tee off after the pressure tank and air scoop or can I go closer to the tank. (Spot 1 vs Spot 2 in the picture) Should there be a check valve on the supply from the boiler? Do I need a Hy-vent?

On the return from the indirect tank I will add the circulator pump. Do I need a wye mesh strainer before or after the new pump? Do I need a strainer at all? Do I need a check valve?
The return piping will be tied in below the current circ pump for the heating zone.

I am planning to hook the tank up as the priority on a Taco SR503 and the heating zone as zone 2. Please let me know if this looks ok or if there is anything I'm missing. Thanks for the help

Zman

I would research the concept of pumping away before taking on this project. This would be a good opportunity to correct your existing setup.
Dan wrote a great book titled "Pumping Away" which is well worth the investment.

SandysEn

Thanks I will check if my local library has it. Could you please elaborate on what would need correcting? Should the pump be on the boiler supply side instead? I saw a couple of videos on youtube by Richard Trethewey from This Old House and one from Steve Lavimoniere both of which had the circ pump on the boiler return.

EBEBRATT-Ed

Pumping away is considered the best method. However with a low resistance system this isn't mandatory (in my opinion). You need to tee the supply for the indirect in down stream from the expansion tank or trouble will result. Your return connection is ok.

So immediately after the expansion tank install a tee (the tee needs to be between the expansion tank and your existing flow check valve) on the outlet of the tee reinstall the flow check valve for the heating loop and on the other tee connection install a new flow check valve for the indirect supply water.

separate shut off valves to isolate both loops (heating and indirect) are recommended for service ease but not mandatory. Don't forget air vents and drain valves.

If you decide to pump away, put the supply tee in the same spot as above then install both circulators on the new tee pumping away from the expansion tank. Flow checks on the pump discharge

HVACNUT

You really should repipe to pump away.
If you do it the way it shows in your pics, don't run the return across the front of the boiler like that. You need access to swing the front plate of the boiler out for chamber cleaning /repair. Go up 6' from the floor, then over.
IMO, get a small electric water heater and some hose fittings, connect to your washing machine and you have a nice spring project.

SandysEn

Thanks for all the insight

Zman

EBEBRATT-Ed said:

Pumping away is considered the best method. However with a low resistance system this isn't mandatory (in my opinion). You need to tee the supply for the indirect in down stream from the expansion tank or trouble will result. Your return connection is ok.

So immediately after the expansion tank install a tee (the tee needs to be between the expansion tank and your existing flow check valve) on the outlet of the tee reinstall the flow check valve for the heating loop and on the other tee connection install a new flow check valve for the indirect supply water.

separate shut off valves to isolate both loops (heating and indirect) are recommended for service ease but not mandatory. Don't forget air vents and drain valves.

If you decide to pump away, put the supply tee in the same spot as above then install both circulators on the new tee pumping away from the expansion tank. Flow checks on the pump discharge

I have a friend and neighbor who has a setup just like yours. Every couple years I do a quick repair that requires a drain down.
Because it is not pumping away, it takes a while to get all the air out. You can hear is sloshing around for about a week.
I recommend the same thing to her that I will to you. It's not a big deal in a low resistance system like this but if you ever have to do a major repair or boiler replacement you should move the circulator to the other side.
In my opinion, this would be a good time to do it since the pipes will all be open and you will be doing some wiring anyway.