solar or geo tank with intergral 90% mod con backup

Jason Quinn

HR-

Would love to see pictures of final install. Do you have others to show? Looks interesting.

hot_rod

available in several output and capacities

this is a 80 gallon 130,000, LP fired.

It has a coiled HX in the very bottom, looks like a SuperStor coil.

The 5 to 1 modulating burner is mounted about half way up. So the bottom could be for the solar or geo input, and the burner would fire as a backup.

It also has connections at various levels into the tank.

I'll pull the radiant from the mid taps.

Very clever multi purpose backup or primary heat source.

hot rod

[Deleted User]

WHOSZIZIT???

Never seen one of them...

ME

hot_rod

HTP

ME, you ought to have one for that mountain home

I'll feed this with two solar inputs (bottom connections) and pull radiant from the top half. Plenty of applications in mind for this.

hot rod

scott markle_2

who makes that unit?

Does it vent through pvc pipe? , Are you planing any control strategy that will suppress burner if ample solar insolation is available.

It seems to me that if the upper half of the tank is maintained at 120 deg. not all that much capacity for solar collection would be left in the tank. Let's say that stratification leaves 40 gallons at 100 deg. and that 180 is the upper practical limit. That doesn't seem like a huge amount of solar storage capacity.

The same volume of water could extract much more solar energy if it's starting temperature were lower. But this could only be accomplished be suppressing the burner and allowing tank temperature to drop, if it's 9 am on a clear summer day it would be a real waste for that burner to have fired at 8-am after someone took a shower. Do you see any practical ways to address this?

What happened to the oventrop tank? ,

scott markle_2

Open loop?

I took a look at the specs on that unit. The bottom solar coil is an option, and from what I can tell the mid level connections are to the tank directly.

Do you have any reservations about sharing dhw with heating?

Do you think this unit could be used for closed loop heating with the solar coil as HX to a small low temperature radiant setup? or would the temperature drop at the bottom of tank and hx efficiency drop temperatures too low. In my experience with well insulated structures 100 deg. max. supply temperatures are usually sufficient for exposed slabs. If the tank was set at 135 do you think you could get 4 or 5 gpm of 100deg water from that coil

Any idea how hot that tank can be set and still get 94% efficiency

Seems like two coils (low for solar in, mid for radiant out)and submerged burner hx would be the best setup.

hot_rod

All good questions

yes i will give up some solar harvest-ability with a combined tank like this. I've found the 8 tube Oventrop collector will not bring that 60 gallon tank much above 115. At least so far. So that array should be a better match for the bottom half of this tank.

The radiant will be pulled off via a Taco HX VS mix block. No to combined DHW/ radiant Yes to PVC, built by HTP (Munchkin folks)

If I do shower at 8 AM for example the cold enters the bottom, so the solar will begin to harvest as the collector warms.

Ideally in sunny weather enough collector should keep the tank warm enough to not need the burner back up.

Also note the 3 way Caleffi ZV to switch the solar to my heat buffer when the tank is satisfied. This way I have more "places" to store the thermal gain.

It's all new to me, I'm sure others will have unique applications for this product.

The Oventrop dual tank moves to my house to connect to the solar and Knight as back up. It will replace the old Ford solar tank and Phase 3 indirect. Free up some space in that room.

hot rod