Loop Sealing - Anyone?

[virginiatech]

I have a 3 ton Geo system I installed 2 years ago for a customer which has worked great until now, the lake loop piping is leaking and losing pressure. The leak must be very small since it takes 6 to 8 weeks to leak down from 45 psi. Have any of you guys used a sealant product in a leaking loop and if it worked can you provide the name and source of the sealant? I have asked my suppliers and no one offers such a product. My only other option would be to float the loop to check for leaks. Thanks for any help.

[SkyHeating]

I would want to find out where and why the loop is leaking if its not to tough to bring it up, because you want to make sure the mistake is not made again if its your mistake or if its the manufacturers mistake what to look for or lastly if its an environmental factor so you know for future use. We tell customers a loop should never leak and we install close to 50 systems per year without one leaking yet(knock on wood) All but two of ours are in the ground, one is on a floating home and one we are installing(4 systems actually one home) is on a pond.

[lytning]

Didn't think the EPA allowed a loop in a lake, pond or the ocean.

I would want to find out where and why the loop is leaking if its not to tough to bring it up, because you want to make sure the mistake is not made again if its your mistake or if its the manufacturers mistake what to look for or lastly if its an environmental factor so you know for future use. We tell customers a loop should never leak and we install close to 50 systems per year without one leaking yet(knock on wood) All but two of ours are in the ground, one is on a floating home and one we are installing(4 systems actually one home) is on a pond.

[ClarkBP]

I don't think there's any problem with a closed loop system placed in a body of water.

To the OP, I would reccomend that you go ahead with floating the loop and fixing the leak. I know of one installer that used a leak-stop solution (no idea what brand), but it didn't work at all. In the end, he would have been better off finding and fixing the problem.

Good luck!

[lytning]

Local restaurant wanted to use a closed loop in Casco bay. EPA said no way. I guess they were worried about a leak and also heating the water in the summer.
A good (if there is one) truck radiator stop leak ? Probably a good exercise in futility. Mine is exercised
daily.

TE=ClarkBP;16204301]I don't think there's any problem with a closed loop system placed in a body of water.

To the OP, I would reccomend that you go ahead with floating the loop and fixing the leak. I know of one installer that used a leak-stop solution (no idea what brand), but it didn't work at all. In the end, he would have been better off finding and fixing the problem.

Good luck![/QUOTE]

[Adlerberts-Protege]

Did you go cheap at the beginning? Leaks are rare. You had an amateur installing your loops.

[CallaDrilling]

EPA did not approve the bay loopfield because it is just that....A bay.
You must own the waterway your going to use for the loops. In NJ we are not allowed to have closed loops in the bay either, but lakes,creeks,rivers ponds are fine if you own them or have run off to them for open loops.

[GT1980]

... leaking and losing pressure....from 45 psi. ... used a sealant ....to float the loop to check for leaks. Thanks for any help.

in one school a bars stop leak liquid
[not cotton-fibers, etc] worked well, permanently and one bottle per well-loop; but others can advise for you:
however,
the Hydro-Temp, AR, system
has very low pressure drop loop hx not coaxial, generally, (under 4ft tdh in glycol, 2.7gpm/actual compressor label-ton) with I guess more open cross section, etc.) and none of the HX loses performance nor pluggs. Check your OEM, miscible-oil in body of water? May be just presurize and find leak/ as SKY...

Any stop leak with the fibers can quickly get in to the volutes of the impellers of the circulators, or y-strainers that the bars passes right through.

SKY is best above advice, if you can do the likes of adding air pressure
Also?
45 psi? A reservoir in joists off T is only 2 psi and plenty of NPSH over pump inlets at 4ft TDH + (5+ better).

We have systematically since 1983 "left" the pressurized loop world, and never voided a warranty BECAUSE 2 psig is pressure:

The GFos tech said he'd like 6ft but minm 4.1/2 on a ph call about T'd in reservoirs in overhead joists above the impeller of the pump , used commonly since the 70's.
AND
one-size over-sized - T body of the fitting , receiving the EW from the Earth-Coupled ECL, gle, loop-field, to get solution incoming under 4 ft/sec, generally is better (but size of header line does work to purge air).
have used 1.1/2" to 2"T's but 90% 1.1/4" for most 1.1/4" header lines.

This T is 90-deg on its side, EW dead-heading into the horizontal base leg, then splitting to the (a) shut off, to a simple 5 gal carboy (to 15 tons) [ 2.1/2gal 3 ton, 4 pipes or smaller than 1500 ft loops, ] overhead-above in oists or nearly so.
-
some times there before that shut off between it and the T is a t'd boiler drain for future quick customer add-in as AIR EFFERVESCES CONSTANTLY for a few months out of solutions...
Solutions of ground loops are gassing 99% of the time and AUTO-PURGE T-designs need no "splitters" other than the T's

We have NEVER had to add additives to 16-18% methanol (but always if under 24% glycol per dowfrost's recommendations).
The vented reservoir with ~ 4 gal in a 5 gal tank DOES NOT LOSE methanol, as a layer of , bacteria or debris forms on the fluid top in the plastic container.

Many schools, 500+ ton (largest surgical center in GT, US, by 2004) and 30,000 homes of just one OEM most-all have had this and by design, some several years before some OEM's claimed warranties void if no pressure... since the late '70 's - still a fine air-purging today.

The pumps are under the other side of the T-head turned on its side ALWAYS over 4ft TDH for better NPSH and yields better pump performance than standin QT type flow centers. (seen since 1996)

This maintains all flowing well such that even 18 feet ABOVE this T and reservoir, if headers and lines hit that ~ 2.3 to 2.4 feet per second/air-moving out of piping methanol antifrozen, then and IF NO LEAKS at all , it can be in the basement above the pumps, with higher headers, but pump inlets underneath the T.

(that depends on flow and drag and possible cavitation, but an un-pressurized reservoir top will not flood under 18 feet rest of design.)

Systems can run "rather-OK" BELOW Reynolds numbers in lines, headers built for flushing, once the air is gone (99.%)

Just 3% en-trained air can cause some systems to require 2 pumps for some 4-tons sized systems to better-perform, mechanically but then less efficiently...
where as 1 pump works well
to most of today's 4.1/2 and 5 sized-tons to 5 pipe systems (averaging over 20-tons per hp) with a simple T-in reservoir design for most homes, I believe..

[Geo medic]

I have heard of some using a Stop-Leak for pools and spas but i wouldn't reccomend it. Best to find the leak and fix it.

[GT1980]

I have heard of...it.

agreed bests; but even a couple teaspoons of table pepper have found and stopped small leaks in pressurized systems according to a 25 year vet in GT and now dominating in horizontal boring.

Reservoirs T'd in over the flow center just leak slower, if leaking, at having less than pressurized loop problems with leaks that can not be found. - Make sure flow PD is well enough for the NPSH at the pump inlet, though.

[wahoo]

We've switched some older "slow leaking" loop systems (put in by others) to non-pressurized pump/tank systems (made by B&D manufacturing). They work fine.

[GT1980]

We've switched some ... B&D manufacturing). They work fine.

What ChrisJ in the Hydro-Temp q's is referencing is the reservoir over the pumps, which allows for a higher NetPositiveSuctionHead, and smaller pump horsepower per ton.
Not so big a deal but does allow for 1 pump to what is called size 5.5 to size 6 units having 56k to 64k btu compressors inside of the systems.

Grundfos tech in the early 90's with theups 26 - 99 then, said a good 5 ft of fluid pressure, on a T-in , above the pump was great for the performance NPSH assist.
Those pressureless sure are great for air removal as pressurized systems contain disolved air that also interears with pump performance, as heat exchanger and pump OEM's point out in various articles and literature.

you may want to check the cavitation affecting the pumps bodies with those low level reservoir set ups. Reservoirs overhead are hitting 21 years, same pumps.

FlowCenterProducts com has an add-on to improve the low tank flow centers performance, and get a few more btu's available.

[geodean]

we have had good luck with Loop Conditioner from Geothermal Supply for fixing leaks