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Ed K
Hot water heater: indirect or regular?

We're planning on replacing our cracked oil-fired steam boiler (Burnham) with a gas-fired unit (Weil-Mclain). Currently, our hot water system is a SuperStor GL-50 storage tank with a tankless coil inside the Burnham. This tank is about 5 years old and so far is working fine. Our plumber suggested that we replace the tank with an A.O. Smith ProMax 50 gallon gas water heater, instead of keeping the SuperStor and replacing the coil, because it would be more efficient. However, my research shows that indirect water heaters are considered more efficient.
Which would be better for us? Naturally, we're looking for the most efficient water heating that we can afford - less than $1000 for the tank - and our boiler is in the basement and connected to the chimney flue. We live in NYC.

Appreciate any advice you can give me.

Re: Hot water heater: indirect or regular?

I'm not that familiar with connecting a Superstor 50 to a STEAM boiler----these indirects are very widely connected to HOT WATER system boilers and are strongly recommended for such an application.

However, they are also recommended for hookup to a steam boiler & use a pump to circulate the boiler water thu the indirect HWH as a heat exchanger for the domestic HW supply.

I would recommend you try to keep the same arrangement you had with the old boiler & get a 2nd opinion from another installer.

The only difference I can see is that steam system boiler water tends to have much more sludge in it that has to be periodically removed via a drain valve so that the piping doesn't get clogged up.

Re: Hot water heater: indirect or regular?

I would go with indirect, but with the coil in the tank instead of in the boiler like you describe your old system. This is the system we have had very good luck with in both steam and hot water applications.



Ed K
Re: Hot water heater: indirect or regular?

Thanks for your responses. I figured that the efficiency advantage of indirect is significantly higher with a hot water heating system. Since we have a steam system and the heat exchange coil would be inside the boiler, I'm guessing that any efficiency gains would be less significant, if any.

I looked into new indirect hot water heaters, but they're way too pricey for our budget. So, the question now becomes which gas water heater to get. I've heard several complaints about the pilot light going out on the A.O. Smith ProMax. Has anyone here heard the same or experienced it first hand? Has that issue been resolved in their manufacturing? I'm also looking at GE SG50T12AVG as an alternative. It's appealing because it has a 12 year warranty on tank and parts and air vents on the side instead of on the bottom. Anybody hear good/bad things?

EDIT: I found out that most of the problems reported with A.O. Smith ProMax are caused by the vents being blocked by dust, lint, spider webs, etc., causing the safety to turn off the gas. Is this a common issue with water heaters nowadays?

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