extrol tanks

sootmonkey

Yeah, I agree with all of what Dave said. Correct instalation is the key. Most of the compression tanks that I see are not installed correctly. But, replacing Extrol tanks and relief valves every 5 to 10 years can be profitable...if you are on the right end of it.

Maynard

Extrol Tanks

Why Did The Industry Go Away From Expansion Tanks To Extrol Tanks. These Tanks Seem To Be Nothing But A Headache.They Do Not Last...Give Us Back Our Expansion Tanks!

Norm Harvey

I love diaphram tanks, I use all my old compression type tanks as floatation for the dock at my parents lake.

Uni R_2

Failure Analysis

Has anyone done any analysis on why extrol-type tanks fail?

If anyone wants to do some research on this, we could identify certain aspects in why it may have failed like how many feet from the extrol-type tank was the tee leading off or scoop, in which direction the tank was installed, what the max temp for the boiler system was, how many zones the system had, if the system had continuous circ past the tank's tee, if ODR was used, full rupture? etc.

Anyone interested in using/completing a survey on this each time you come across one that has failed let me know and I'll see if I can grab a SurveyMonkey account and open a collection survey for a few months to catch input. Maybe there are better and worse ways to install an extrol tank? There seems to be different opinions just in orientation of the tank out there.

The best thing I ever got from the Wall was the confidence to change my expansion tank to an ET-30 along with mounting a riser pipe to a simple autovent (several years before my upgrade). That one single step eliminated air from blocking the upstairs monofolo fintube loops every two or three months. Crap like that was what lead me here.

Water will go into solution and come out at the lowest pressure points in the system... the bedrooms. No thanks... they do last longer but in a 2 storey house they aren't worth the bother of a waterlogged tank once or twice a year for the case here.

Norm Harvey

I'll participate

Unknown

Ex-Trol tanks,

can, and will fail because they employ a man-made water-to-air separating device(diaphragm)to retain the air. The quality of the diaphragm depends on the manufacturers reputation regarding osmosis,(remember balloons when we were kids?) Some lose their air faster than others without untying the knot.

Yes as UniR says, location is a factor of function-ability, but not much as far as lifespan. Sorry to burst your bubble,and our advice was so crappy!

A properly sized(and located) galvanized tank, with(my choice), the B&G Airtrol fitting, outlasts them all.

Dave

Mars_3

what about wall hung mod cons?

I understand that the compression tanks will have a longer life expectancy than a expansion tank, if one looks at the mod con boilers produced today there would have to be modifications made to near boiler piping to accommodate a compression tank. as well as the fact that the compression tank can and does on certain systems fill to capacity and requires draining. often home owners who have purchased a home with an older hydronic heating system are not aware of the maintenance requirements necessary for an older system. as usual it is up to us in the field to educate the general public as to what there systems need for maintenance. As far as the debate between compression tanks and expansion tanks are concerned I feel that expansion tanks will work better in my market and with my systems.

Weezbo

nah...

waterlogged tanks bite.

hot_rod

O2 ingress is the main cause

of expansion tanks failure on MODERN hydronic systems, in my opinion. Even with barrier pex a small, maybe large amount, of O2 still gets in. If it's pin hole leaks that you are talking about.

Expansion tanks, properly sized and installed seem to last decades on copper fin tube/ cast iron or copper boiler systems without plastic tube in the mix.

hot rod