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Water heater or Boiler?

Ghetto Wash

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I've always called them boilers, but have heard others call them water heaters. One of mine died and I need a new one. In looking at Lochinvar's website, they have water heaters and boilers and they look the same to me.

Whats the difference and which one do I need?
 

Ghetto Wash

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I think that if it is 200K BTU and above it is considered a boiler.

I just rechecked Lochinvar's website, they have boilers and water heaters up to the millions of BTU/hr.

At two of my locations, the "heater" draws water from a tank that is pressurized with city pressure and then back to this pressurized tank. At my other locations water is drawn from the rinse tank (open to atmosphere, no pressure) to the "heater" and back to the rinse tank. I assumed the one with the pressurized tank was a heater and the one with the open tank was a boiler.

?????????? But I'm just guessing.
 

MEP001

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I think technically a "boiler" has the ability to heat water above 212?, but most of us have called the unit separate from any storage tank a boiler. A heater is what most people have in their home, a combined heating unit and storage tank.
 

JGinther

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How much Btu/h is your current system? Have you looked into tankless? If the one that is shot is the closed loop type (versus the open to atmosphere type) the tankless can make a huge difference, let alone space savings. The condensing units are even efficient enough that (on some units) you can actually vent using PVC pipe, and direct vent so that you don't have to have louvres for combustion air - saving lots of parasitic energy on equipment room heat if you live in a cold area, and preventing the risk of equipment room freeze-ups. We have some pics of installations...

Good luck
 

Ghetto Wash

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Called Lochinvar.

A boiler is used in a closed loop system with no new fluid added except for makeup on occasion. Like floor heat.

A water heater is when new water is added and heated when the existing hot water is used.

By these definitions all my "hot water machines" are water heaters, not boilers.

They have different safety equipment on them, so aren't really interchangeable. If you do use one when the other is used, the heat exchanger can fail prematurely.



JGinther, 495,000 BTU/hr. It is used in the open tank style. I have thought about tank-less, but would require other plumbing modifications that I don't want to undertake now.
 

JMMUSTANG

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Be careful with what you get.
Where I'm from the county and the state have to inspect "boilers" but not hot water heaters (250,000 btu's or less) and large compressors.
The cost of inspection is around $100-150 each for each boiler and compressor every year.
At one of my washes (5 & 1) I put in a large hot water heater and a smaller compressor to get buy the inspection and fees.
 

MEP001

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We don't have compressor inspection requirements, but they do inspect boilers. It's not much and it's only every two years, but they always seem to find something wrong every time even though it passed that way last time. I'll bet if the guy who gave us a warning about a check valve last year comes around again next time and tries to fail us for it, he'd take some cash to make it suddenly become a non-issue. Regardless, when the boiler fails I'll switch to tankless heaters.

I recently replaced an ancient boiler for someone with a single Paloma PH28 series and used a tempering valve to mix down the water. It's more than enough flow for his 4-bay, and he has very poor city water pressure.
 
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