Tankless Water Heater or HLT

[JR2018]

I'm looking at starting up a small brewery and I have seen a local brewery utilize a Tankless Water Heater instead of a Hot Liquor Tank for sparging Mash and for cleaning operations. It is a Honeywell unit and they claim it works well for them. Anybody heard of this or have experience in this type of setup? Looking for pros/cons of this approach...

Thanks,

Jeff Reid

[infinitybrewer]

I'm currently working with a tankless system, 2 in series for a better flow rate. 7 bbl brewery @ approx. 1100 bbl per year. We recapture our heat ex water in the mash tun for cleaning purposes. We mash in and sparge with the tankless heaters, and it works well, though without 2 in series the flow rate would not be sufficient.

Pros - you always have hot water and can pretty much dial in the temp you want.
- free up floor space, which in a small brewery comes at a premium (I would rather fill that floor space with another fermenter).
- you aren't burning energy to keep a tank of water hot (when there is no demand).

Cons - you can't measure volume without a good flow meter (the ones rated for high temps can be expensive).
- while mashing in or sparging, you can't really use hot water anywhere else in the brewery.

Overall, I like the system. I've worked at breweries with HL tanks and liked those too, but if I were putting in a small brewery, I would go with a tankless system.

Hope this is helpful. Cheers
infinitybrewer

[JR2018]

Infinitybrewer, thank you for the information.

What kind / model of tankless unit did you go with? Electric or Gas? Also, what is your sparge flow rate in GPM?

Cheers,

Jeff

I'm currently working with a tankless system, 2 in series for a better flow rate. 7 bbl brewery @ approx. 1100 bbl per year. We recapture our heat ex water in the mash tun for cleaning purposes. We mash in and sparge with the tankless heaters, and it works well, though without 2 in series the flow rate would not be sufficient.

Pros - you always have hot water and can pretty much dial in the temp you want.
- free up floor space, which in a small brewery comes at a premium (I would rather fill that floor space with another fermenter).
- you aren't burning energy to keep a tank of water hot (when there is no demand).

Cons - you can't measure volume without a good flow meter (the ones rated for high temps can be expensive).
- while mashing in or sparging, you can't really use hot water anywhere else in the brewery.

Overall, I like the system. I've worked at breweries with HL tanks and liked those too, but if I were putting in a small brewery, I would go with a tankless system.

Hope this is helpful. Cheers
infinitybrewer

[infinitybrewer]

Jeff,

We went with Rheem model # RTGH-95DVLP-1. Temperature affects flow rate, so @ 170 - 172F during sparge we achieve 5 GPM, which is more than sufficient. These are LPG units and we have a LPG direct fired kettle so it was a natural choice. The first 2 lasted 10 years, we just installed new ones. Make sure you are pricing commercial units (not domestic units) because you need the higher temp settings that commercial units provide.

Cheers,
infinitybrewer

[TGTimm]

Check your water quality. If you have high hardness, particularly carbonate hardness, you'll be spending a lot of time cleaning the units--and likely reducing the life of the HXs inside, or investing in water treatment, which you probably should have anyway.

We run three propane Rinnai 199C units to heat our 40 bbl HLT. The best output we get at about 70 F delta T is 6 gpm from each unit, for ~18 gpm total. For a small brewhouse, the low flow rate might be acceptable, but now for a 20 bbl house.

I have to acid clean the units every two weeks, and the little strainer filters get cleaned a couple of times a day.

[Jamierat]

How do you measure volume?

[mswebb]

My biggest concern would be one or all of the units crapping out during my brew process (ie. sparge). If my boiler or HLT are acting up, I don't start the brew. With an HLT I have all the water I need to complete my brew.

Obviously, lots of folks use them but I still like to have the HLT. If you are too tight on space consider a combo unit with the HLT above or below one of the other vessels.

[TGTimm]

How do you measure volume?

Not sure what you are asking. Brewery equipment is usually measured in Brewer's Barrels--bbl. 1bbl=31 gallons.

[JR2018]

Thanks to all in your responses, very helpful info. - wanted to get a feel for how many brewers out there doing this. Seems quite a few so I'm going to check it out further.

Cheers!

Jeff

[gitchegumee]

A waste of energy, water and money....

If you do your job well, there's no reason to use this much water to "clean". Certainly not that much hot water--I don't use hot water at all in our cleaning regime, save for the occasional kettle CIP. The standard brewery method of HLT allows you to fully capture heat and water for next brew. Much more efficient. Much less waste.

[beerme]

Using a tankless heater is convenient in some cases, but it is wasteful of water and energy. I assume you cool your wort with a plate heat exchanger. Dumping the hot water down the drain wastes both water and energy.

You would need a pump and hot liquor tank with a heater (some breweries use the kettle to heat water but it is a pain.) Vs a tankless heater (or two). I don't know if you can use the tankless water heater with a pump to heat the water from your tank, which could be a hybrid. check manufacturers specs. Part of the choice is cost of equipment and part is space to install them.

If you only brew once a week then recovering the heat from the previous brew is impractical since it would cool off before you use it again. A compromise is to get a hot water tank and use the recovered water for cleaning, and maybe even keg cleaning.

it depends on how often you brew, how much space you have, how much you care about wasting water.

[Starcat]

Considerations

Check your water quality. If you have high hardness, particularly carbonate hardness, you'll be spending a lot of time cleaning the units--and likely reducing the life of the HXs inside, or investing in water treatment, which you probably should have anyway.

We run three propane Rinnai 199C units to heat our 40 bbl HLT. The best output we get at about 70 F delta T is 6 gpm from each unit, for ~18 gpm total. For a small brewhouse, the low flow rate might be acceptable, but now for a 20 bbl house.

I have to acid clean the units every two weeks, and the little strainer filters get cleaned a couple of times a day.

I will add to what Timm has stated.
Tankless Hot Water Units are an " affront " to any sane Mechanic and an unfortunate sign of the times.
I could write volumes on the subject that many would not like because it will get too close to the truth.....
Some facts for your consideration.

They can be made to work on smaller scales.
Go with the best brand you can find with the most rugged construction which will still be loaded with plastic.
They will wear out, give trouble, and fail faster than anyone thinks.
Even on very good water they scale up double quick, because they are an attempt to heat water TOO QUICKLY.
You need in inhibited Sulfamic acid cleaner in most cases to deal with cleaning and slow down the destruction of your copper HX.
Products like " Flow Aid " are worthless for cleaning and will not do the job.
The Diagnostic Flow chart for the units I have to service is fully ridiculous, even for someone with Master Level HVACR skills.
They are throw away technology that will be in the Junk yard while any Scotch marine Steam based system will be running for scores of years later.
The are unreliable and unstable on a good day, while steam is 1000x more reliable if set up and installed and maintained correctly.

Read all former threads on the subject.

Star

[I Like Pints]

Where to source

You need in inhibited Sulfamic acid cleaner in most cases to deal with cleaning and slow down the destruction of your copper HX.

Where's a good place to source "inhibited sulfamic acid"?? Birko? Five Star? Water usage rate at what water temp are you using it at?

I've got a difficult heating element to clean...

[TGTimm]

We get ours from Wesmar. It's their DSR.

I've tried several different products for cleaning/descaling the heaters. The recommended chemical is distilled vinegar--which is very expensive when you're cleaning three units every two weeks, and stinks. Based on the color of the cleaning solution after cleaning, inhibited sulfomic acid seems to be doing the least amount of damage to the copper HX.

I make up a solution of 2 oz of Wesmar DSR to four gallons of water, which gives me a pH of ~2.0 with our hard, buffered water at around 130F. I use test strips to monitor the pH, and when it hits ~4.0, I add another oz. of DSR. When the pH stabilizes at ~2.0, I'm done cleaning.

[I Like Pints]

Thanks Timm,

Is this solution something I could CIP with? Sound more like you're soaking/recirculating with it...

-Scott