Indirect Losing 4 degrees/hour

bruce pirger

MegaStor 53 gallon indirect tank plumbed off the primary loop with 1" copper and 010 Taco pump. When no hot water is used in the house, I loose about 4 degrees per hour on the sensor in the MS-53 (363 controller reads sensor).

The 1" lines include "thermal traps" to keep the hot water in the tank and not flowing from primary to indirect plumbing. They consist of 1' length "down runs". There are no one way flappers (can't remember the proper name...sorry).

The 1" line remains quite warm...I assume I am loosing heat from the tank back into the system. The primary loop itself is cool to warm...the DHW 1" is quite warm.

Should a "one way flapper" been installed to prevent this thermal flowing?

The 1" line is NOT insulated...so this may help considerably. Only talking about 10' or so total 1" line. Primary loop is over (above) the DHW tank, but there are the 1' thermal traps...

I guess I expected much less loss from the DHW. Tank itself is not warm to the touch...I assume most of the loss is coming from the thermal flows.

Is it standard to install the directional flow flappy things?

This was professional installed...I am very pleased...and current I burn about 0.5 gallon of fuel in my G115-21 to keep the water warm.

Joe_13

Check valve shoud be on the DHW loop

Recommended in the install manual.
Also how far is the MS53 from the boiler?

hot_rod

heat migration

fairly typical (hot goes to cold, always and even in pipes

I have had some cases where a zone valve was the only solution to the small, short loop migration, I have tried thermal loops with limited sucess, most didn't work. One did but was six foot from ceiling to floor! The weighted type flow checks can, and wiull leak small amounts, best to use a motorized zone valve, I've found. Use a large port styly. Those old WR 1361's were great for large gpm applications. Most other ZV manufactures have high flow models available now also.


Yes, as Joe noted the migration could be on the domestic side also. Some manufactures have those flow stopper dielectric nipples, or add a check. Make sure you provide a thermal expansion tank on the domestic side if you start installing checks there.

hot rod

bruce pirger

Thanks guys. The hot water manifold that feeds the house (I have home run Aquapex runs) does not feel warm at all...so I don't think there's much loss there.

The checks would probably make the difference...the motorized valve even that much better. My thermal traps are 1'...not 6'! LOL I guess at that height they'd work pretty good.

I'll bring it up when the folks come back to finish my install. It's been plenty warm...I think they are busy with AC demands...LOL.

Thanks again!

hot_rod

The easiest fix

may be installing a circ pump with an intergral check. Both Grundfos and Taco offer them. Save the other pump for another job.

I must say sometimes you will still get flow up the other leg, with only one side checked. The pump switch out is an easy first step, if not completly satisfied with the result add a check or zone valve on the other leg.

Or add the check pump AND a spring check on the return side to fix it for sure with just one trip back

Be sure you are not merely feeling heat conduction in the copper piping, sometimes confused with small heat flow symptoms.

Wouldn't hurt to insulate all that near boiler piping also for additional energy savings.

hot rod

Joel_3

megastor

The ms 53 is a great tank 1 leak point i've observed of heat though is at the top there is a removable cover under the plastic this is NOT insulated wouldn't hurt to pop off the plastic and do something with it

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