Life expectancy of EPDM liner -Anyone with an EPDM lined tank that's 5+yrs old?

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mole

Member
Oct 23, 2008
158
Western NY
I built an EPDM lined tank this fall, which I'm loving so far. I let my fire die back as the tank peaks out at 170F and so far I have not gone over 173F. I've been thinking that maybe I'm being overly cautious. Now as I read the latest threads on EPDM liners, especially the gentleman whose liner started weeping at 7years with 180-185degree tank, I'm not so sure what to expect. I know the prevailing wisdom is that the 40mil EPDM will last about 10years at 170-175 peak service temp. I'm very curious to hear how long most liners are actually lasting and the actual operating temperatures they see. I would appreciate if anyone who has had an EPDM lined tank for 5 years or more could share:

1) How long in service
2) Average peak charging temperature
3) Highest temp tank has seen
4) Condition of liner, issues, concerns

Maybe we can get a clearer picture of actual life expectancy and the relationship between service temperature and service life.

Thanks, all.
Mole
 
fired my tarm 40 with 806 gal stss storage tank on 10/31/08. I've seen a few temps above 182 but that's my limit. I'll try to stay down around 170 but it's hard my first year. I sure do enjoy the radiant heat. I hope it will last too. sweetheat
 
I've worked on a few Chiles Power Systems here in Missouri with 16 plus years on them. Mike and Dan Chiles started Heatway years ago. Before that they built log homes and solar/ wood boiler systems. Dozens were installed in this SW Missouri area. Some had wood boilers built in Missouri, a few had Royall wood boilers. All of the ones I have serviced had plywood tanks with EPDM liners. Three or 4 coils of K copper for input and output. They operated right around the 180f setpoint.

Solar input was provided by the old Solaroll EPDM mats on the roof. I still have some of that tube.

The most common failure I saw was the copper coils pinholeing. In an open tank with no care taken to balance the Ph the tube, even heavy K copper would pin hole after time. Although 16- 18 years is a good track record.

I have never seen any failed liners. These were was plain roofing EPDM, not very thick. I've dismantled two of these systems and kept the EPDM to cover my wood pile :) And the Royall boilers were re-sold to friends and are still in service. 1982 date code on one!

hr
 
free73degrees said:
Great questions. I'd like to add:
5) What brand and thickness of liner

Free73degrees, good idea, thanks. Did you lose 2degrees in the recession?

Sweetheat, thanks for the info. I'm hoping there are some veteran tank owners out there that can contribute too.

Mole
 
in hot water said:
I've worked on a few Chiles Power Systems here in Missouri with 16 plus years on them. Mike and Dan Chiles started Heatway years ago. Before that they built log homes and solar/ wood boiler systems. Dozens were installed in this SW Missouri area. Some had wood boilers built in Missouri, a few had Royall wood boilers. All of the ones I have serviced had plywood tanks with EPDM liners. Three or 4 coils of K copper for input and output. They operated right around the 180f setpoint.

Solar input was provided by the old Solaroll EPDM mats on the roof. I still have some of that tube.

The most common failure I saw was the copper coils pinholeing. In an open tank with no care taken to balance the Ph the tube, even heavy K copper would pin hole after time. Although 16- 18 years is a good track record.

I have never seen any failed liners. These were was plain roofing EPDM, not very thick. I've dismantled two of these systems and kept the EPDM to cover my wood pile :) And the Royall boilers were re-sold to friends and are still in service. 1982 date code on one!

hr


In Hot Water,
That's great info and very encouraging on the EPDM end. It also speaks for the need to treat the tank water to minimize corrosion- which I haven't done! Thanks!
Mole
 
mole said:
Did you lose 2degrees in the recession?

Good catch. My wood is free (see name ;^) so the recession is not the reason for the name change. 75 is just too warm. 73 might even be a little warm. Maybe free71 would be better.
 
free73degrees said:
mole said:
Did you lose 2degrees in the recession?

Good catch. My wood is free (see name ;^) so the recession is not the reason for the name change. 75 is just too warm. 73 might even be a little warm. Maybe free71 would be better.


Fine tune with wood. I like that.

Very good post / questions. I'm planning to build two tanks and will be watching closely.
 
Can flat plate heat exchanger be mounted inside the tank under water, if so what are the advantages or disadvantages??Dave
 
TacoSteelerMan said:
Can flat plate heat exchanger be mounted inside the tank under water, if so what are the advantages or disadvantages??Dave

hmm that's an intriguing and new idea-

advantage is that losses from HX go straight into tank, instead of ambient surroundings, so there would have to be some p,

disadvantage is the the pump for the tank side is usually not submersible-- so there would have to be some plumbing to get from the HX out of the tank back into the tank

I guess the one other disadvantage is that if you need to clean/ flush the plate HX, you'd need to drain the tank or go for a dive to go get it and be able to take it out
 
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