Best type of tank for indirect water heater

sasquatch16

Currently have a Vaughn S70TP that is leaking. Manufacturing date is 1004 so I assume this is October 2004? This is a stone lined tank. I see Vaughn now has a plastic lined tank. Is this better? Is 15 years from the stone lined tank considered good? Will the plastic last longer? Also are there other types of tanks I should be considering?
Thanks

Alan (California Radiant) Forbes

Many companies have stainless steel tanks in their product line. In my opinion, they are the best when it comes to indirect water heaters. Of course, they are more expensive than lined steel tanks and usually have a limited lifetime warranty.
Within the last 2 weeks, two of my customers have needed indirects replaced; both of them were lined steel tanks and both were about 15 years old. And neither of them had their anode rods checked or replaced which could have increased their lifespans.

Zman

The concrete lined Vaughn's did an excellent job of keeping the house from blowing away, not much fun to move around though . Beyond that, the heat exchangers were prone to calcifying and the gaskets had a tendency to leak.

Unless your local water has high chlorides, the stainless models with oversized coils seem to work best. Heatflo, Lochinvar, HTP.....

hot_rod

Test your water first, note the chloride limits on stainless that voids all warranty. Select a tank that best matches your water quality.
Overall my best experience has been with smooth coil, glass lined steel. It varies from area to area, based on water quality.

Water quality, amount of use, operating temperature all all part of life expectancy.

Anode rod maintenance is often overlooked and can make years of service life difference. Even some of the stainless tanks now sport anodes.
Local plumbers and wholesalers usually know what type of tank holds up best in an area, as they warranty them😳

bob eck

Stone lined tanks, plastic, glass lined and SS all have their place in the market.
Vaughn stone lined you need to watch the gasket at the coil. If it leaks replace the gasket ASAP. If this was done you the Vaughn indirect water heater could have lasted 20-25 years.
The Vaughn Featherweight plastic indirect water heater I believe uses the same coil as their stone lined IDWH. Watch the coil gasket.
The Vaughn stone lined and plastic the home owner can turn their 10 year warranty into a lifetime warranty by sending in the warranty card and buying the lifetime warranty.
Stainless Steel tanks there are many grade of SS used. Check water for calories.
Bradford White has a nice SS indirect water heater and that has a lifetime warranty.
Glass lined are a good tank but the anode rod should be replaced every 2-4 years. Most home owners never have their glass lined indirect water heater, electric or gas tank type water heater anode rode pulled and replaced on a regular basis. Doing this you can extend a glass lined unit a long time.
You also need a good thermal expansion tank on the system and you need it sized correctly and that tank also needs to be checked on a regular basis and replaced as needed.
Indirect water heater, tank type electric or gas water heaters all should be flushed out on a regular basis.
Most glass lined indirect water heaters have a 5 to 10 year warranty.
Like Hot Rod said get your water tested and check the manufacturer warranty on water quality limits.

flat_twin

Bock glass lined indirects have a lifetime warranty for residential use. They have two anode rods and a large diameter glass lined heat exchanger.
Our previous glass lined electric water heater lasted 23 years and was replaced out of concern for it's age. The anode rod was never replaced.

hot_rod

As far as I know the Bock, and Caleffi tanks still have a good coating 12- 15 mil of that AO Smith Permaglass, as do the coils. Still a 12 gauge tank, 7 gauge base and heads. Even the jackets were made of heavier gauge metal, compared to box store tanks.

Plenty of those blue AO Smith Harvestore Permaglass silos still standing dating back to the 1940's.

Mike M

1940???WOW!!!!!

mattmia2

Were there monel indirects?

hot_rod

mattmia2 said:

Were there monel indirects?

Copper or red brass tanks? I don't know of any metal or alloy that can withstand all the water quality concerns, temperature stresses, etc.

I think polymers or composites may have the best chance if they get the engineering correct on the connections and holes into the vessel.

Or could the chemicals leach out from the water treatments being used now or in the future? So the tank is indestructible, it's maybe slowly killing you

mattmia2

I've heard that there were monel direct fired water heaters, they were making copper indirects in the UK on how its made

kcopp

Another option on a glass lined steel tank would be an electric powered anode.
I have used these when the aluminum/ magnesium anodes have reacted w/ the water. No odors or cloudy water and they have a long lifespan.
http://www.productpreservers.com/

sasquatch16

Starting to get quotes on new tank and getting confused. Currently I have a 70 gallon stone tank. All agree I do not need that big. Where the confusion is is in the way it is plumbed. I have a circulator with two zone valves for my heat. I have a separate circulator just for the hot water. The one plumber says I should get rid of circulator for indirect tank and install an additional zone valve set up as priority for hot water. Right now I assume circulator for hot water can run at same time as heat.
Obviously this is a lot more money.

GroundUp

sasquatch16 said:

Starting to get quotes on new tank and getting confused. Currently I have a 70 gallon stone tank. All agree I do not need that big. Where the confusion is is in the way it is plumbed. I have a circulator with two zone valves for my heat. I have a separate circulator just for the hot water. The one plumber says I should get rid of circulator for indirect tank and install an additional zone valve set up as priority for hot water. Right now I assume circulator for hot water can run at same time as heat.
Obviously this is a lot more money.

I'd be looking for a new plumber. Indirects work best with more flow and a dedicated circ is going to outflow the alternative by a large margin, but it ought to still be set as priority

sasquatch16

Wiring and controls are a mess. Where can I find info on best way to rewire. Looks like I have a control for boiler and control for the indirect heater.

GroundUp

What model is the boiler? It may be worth considering the switch to something like a Taco ZVC406 zone valve controller, to integrate all control wiring into a single box. This would run the zone valves and boiler circulator, as well as spin the DHW circ on heat call from the tank's aquastat. A heat call from anywhere would also close the end switch and signal the boiler to come on. It may or may not fit your particular arrangement, but it may be a step in the right direction to clean everything up. I'm no electrician by any stretch of the imagination, but know almost enough to be dangerous so please take my thoughts on the subject with a grain of salt

mattmia2

Pictures would help. dressing and labeling can really clean a wiring mess up.

Normally the indirect will have an aquastat that will connect to the boiler control although there are more integrated solutions.