Primary/secondary open storage piping challenge

[hkobus]

I am working on finalizing the plan for the re-work of my system, the Eko and floor heat have worked very well for the last two seasons and now I want to graduate to a system with back-up and storage. Everything has run without any added controls so-far other than the Eko control and a miximizer for the floor heat.

The challenge is working in the storage charge and discharge with close spaced t's. In my mind this does not work since I will use two circ's to reverse the flow through the coils to save cost. (both check valves removed) ( there is the Dutch in me ;-) ) When I hook it up the normal way, it should charge correctly, but at discharge it would short cycle due to the fact that the primary loop keeps going clockwise. ( I attached a file to illustrate this all, the 3 tanks are the 3 scenarios)
The idea I got was to use a Taco Twin-Tee and fix it that way, the tee is than not in-line but side by side and should stop the short cycle. When I checked for cost and availability, I first got sticker shock and than they said it would be at least a few more weeks to get it ( not a stock item anymore in Canada)
The following idea is not tried but straight from the farm engineering department. I am thinking of using a 1" brass cross piece in place of the Twin Tee, I hope this reduces the cross flow but I am considering placing a "baffle" from the top of the one sec.port to the bottom of the other sec. port.

The question is, would this work?
Any comments welcome,

Henk.

 

[ewdudley]

So there would be piece of copper plate soldered in parallel with the primary flow?

I can't see much difference between flows entering and leaving at right angles in the same plane as the baffle -- as is the case with the Twin-Tee -- or flows orthogonal to the baffle -- as in the case of the cross. The secondary flows have to make a 90-degree turn and go with the flow in either case. Looks like a winner to me.

BTW any fan of farm engineering should check out Farm Show Magazine and sign up for the free issue:

http://www.farmshow.com/issues/33/06/3306.asp

--ewd

 

[hkobus]

So there would be piece of copper plate soldered in parallel with the primary flow?

I can't see much difference between flows entering and leaving at right angles in the same plane as the baffle -- as is the case with the Twin-Tee -- or flows orthogonal to the baffle -- as in the case of the cross. The secondary flows have to make a 90-degree turn and go with the flow in either case. Looks like a winner to me.

BTW any fan of farm engineering should check out Farm Show Magazine and sign up for the free issue:

http://www.farmshow.com/issues/33/06/3306.asp

--ewd

That was my thought, but on more than one occasion my thoughts have been less than perfect. I would like to try without the baffle, but one just never knows. I do believe the primary flow will have the right effect on the secondary flow leaving and re-entering. I may even place some unions to make access for modification easier.

Thanks,

Henk.

 

[Nofossil]

I don't have a picture, so I'll have to use a thousand words. I think this works....

Three closley spaced tees.

1) The first (upstream) tee goes through a check valve to the top of the storage HX coil. Check valve flows towards the top of the coil.

2) The second tee connects to the two back-to-back circs, which are connected to the bottom of the HX coil

3) The third tee connects through a check valve to the top of the HX coil. That check valve flows from the top of the HX coil towards the third tee.

Flow during charging: the charging circ drwas from the bottom of the HX coil and discharges to the middle tee. Water is drawn from the first tee. Life is good.

Flow during discharging: The discharge circ draws from the center tee and pumps water into the bottom of the HX. Water from the top of the HX can only go to the third tee. Life is still good.

Does this make sense? Wish I had a few minutes to sketch it.

 

[ewdudley]

That was my thought, but on more than one occasion my thoughts have been less than perfect. I would like to try without the baffle, but one just never knows. I do believe the primary flow will have the right effect on the secondary flow leaving and re-entering. I may even place some unions to make access for modification easier.

Graag gedaan.

Without the baffle wouldn't the secondary flow just shoot straight across a fair amount?

I don't have a picture, so I'll have to use a thousand words. I think this works....

Three closley spaced tees.
...

Flow during charging: the charging circ drwas from the bottom of the HX coil and discharges to the middle tee. Water is drawn from the first tee. Life is good.

Flow during discharging: The discharge circ draws from the center tee and pumps water into the bottom of the HX. Water from the top of the HX can only go to the third tee. Life is still good.

Does this make sense? Wish I had a few minutes to sketch it.

Yes this looks like a sure thing as well. If pumping through the dead pump would be problem you could add two more check valves a build a full-wave bridge rectifier, but now we're getting off into Rube Goldberg stuff.

--ewd

 

[hkobus]

I don't have a picture, so I'll have to use a thousand words. I think this works....

Three closley spaced tees.

1) The first (upstream) tee goes through a check valve to the top of the storage HX coil. Check valve flows towards the top of the coil.

2) The second tee connects to the two back-to-back circ, which are connected to the bottom of the HX coil

3) The third tee connects through a check valve to the top of the HX coil. That check valve flows from the top of the HX coil towards the third tee.

Flow during charging: the charging circ drwas from the bottom of the HX coil and discharges to the middle tee. Water is drawn from the first tee. Life is good.

Flow during discharging: The discharge circ draws from the center tee and pumps water into the bottom of the HX. Water from the top of the HX can only go to the third tee. Life is still good.

Does this make sense? Wish I had a few minutes to sketch it.

Yes, this does make sense. I had gone through this thought too, but don't really like check-valves that much. They are still costly enough and with that much use tend to start rattling over time, we have them in some of the floor heated nursery barns and you can hear them throughout the building, when they quiet down it usually means you have a problem....
I may however end up with it but still would like to try the cross if not for it's simplicity.

Thanks,

Henk

 

[hkobus]

Graag gedaan.

Without the baffle wouldn't the secondary flow just shoot straight across a fair amount?

That is what I am wondering too, I take it there may not be much experience with this? en bedankt!

Yes this looks like a sure thing as well. If pumping through the dead pump would be problem you could add two more check valves a build a full-wave bridge rectifier, but now we're getting off into Rube Goldberg stuff.

--ewd

I'll let you know when I am realy for the wave pool.... :lol: