Return to storage location?

[goosegunner]

I am finally going to start piping storage but I am having difficulty understanding what is the best method for my situation, Simple Pressurized drawing, Hydraulic separator, or a mix. of the two.

Details;

Econoburn 200
Danfoss return protection
1000 gallon horizontal lp tank
2" ports top and bottom both ends
Swimming pool in the summer that can create high delta t


Questions

If I use the Simple Pressurized drawing will low temp return water, 100 degrees cause issues because of the direct path to the boiler? (I do have a Danfoss in place)

Would it be better to return water to one end of tank to temper as it travels accross bottom and then out opposite bottom end to boiler return?


If I Plumb like a hydraulic separator, Boiler supply and return to one end and then use the opposite end for Load supply and return, be better to buffer the lower temp return?

Will hydraulic separator method on a 42" diameter tank cause the water to short cycle or just circulate on one end of the tank?

All for now

gg

 

[jebatty]

I also have a 1000 gal horizontal LP tank, but an older model with a 36" diameter. My thoughts:

If I use the Simple Pressurized drawing will low temp return water, 100 degrees cause issues because of the direct path to the boiler? (I do have a Danfoss in place)

Your boiler is rated at 200,000 btuh output, which I take to be maximum, and more likely operating range of about 150,000 btuh. At 185F output supply and 100F return, delta-T =85F, that's 3.5 gpm flow rate. You will have a mixing valve to mix down the supply to the pool, that is, not supply 185F water to heat the pool? Won't that by itself result in a higher return temperature? And with the Danfoss boiler protection mixing valve, I see no problem. I have a Termovar and have no issue with 100F tank return temperature to boiler, post-Termovar 160F return to boiler. Adjust the balancing valve on the Danfoss as needed to achieve the boiler protection return temperature that the mfr recommends for the boiler.

I assume you are using a plate hx between the tank and the pool. That would alter the numbers somewhat due to efficiency loss through the plate hx.

Would it be better to return water to one end of tank to temper as it travels accross bottom and then out opposite bottom end to boiler return?

For reasons already stated, I see no reason to do this.

If I Plumb like a hydraulic separator, Boiler supply and return to one end and then use the opposite end for Load supply and return, be better to buffer the lower temp return?

I don't see why any additional buffering is needed other than as indicated.

Will hydraulic separator method on a 42†diameter tank cause the water to short cycle or just circulate on one end of the tank?

I don't believe so. Hot water will move across the top of the tank and cool return water along the bottom of the tank. Your flow rates are quite low in pool heating due to large delta-T. Even with tank charging and pool heating not in operation, I doubt you will get any direct supply/return circulation. My tank stratifies extremely well on tank charging only, and I supply/return from boiler just like you describe.