Tankless Water Heater & Mash Temp

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Jknapp

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I'm getting a tankless water heater installed next week. The plumber says I can set the temp of water to whatever I want with the digital controller - max temp of 180. He's going to install a valve in my garage for when I brew -
I will be able to get mash-temp water on demand at my brew station, which will be cool.

Anyone else using tankless water heaters for their mash water? If so, how is it working out?
 
180!?!?!? Maybe if the flow is very low. Typical tankless heaters are installed and pre-set in the 110-125 range. I have a high volume Noritz because we have a very cold ground water in the winter and high flow shower that draws a heft 7+ gpm when going full-bore (although we usually set to about 2.5 gpm)...

BTW, the ratings and such are skewed because they are not typically tested on equal footings between manufacturers.
 
1. do you filter the water going into the heater? you might want to do that.

2. is your garage valve going to cut off the supply to the rest of the house? it should or someone might have a nasty shower surprise.
 
That's a pretty similar unit to the one I have, which works well in Chicago (my ground source water is currently 47 degrees, FYI). Here is the critical section in the specs:

"Turbo Flow - Up to 11.1 GPM @ 35 degree temperature rise (8.4 GPM @ 45 degree rise)."

So, what is the temp rise from your source water temps? To go from nominal 60 degrees to 180 is a 120 temp rise, so you aren't going to want to leave it set at 180 as your home default!

Don't let that keep you from getting one, IMO they're absolutely great.


Also, if you have municipal and/or treated water, you do NOT need a whole house filter on the source side. If you have a water softener and you might want one. But these things come with 10 yr full warranties (mine did through my installer who only does tankless) and I have had early Bosch models in my parents' home (2 of em) and they have been going strong with minimal service for 22 years now)
 
You have to do something to override the defaults to get it to go up to 180.. I am unsure what that something is, but can find out from the guy who did it to mine if you need me too. I don't doubt it can output water up to 180.. They are a beast. I tried 145 just as a test and it handled it without any issue at full pressure..
 
John, do you have a Noritz? Mine has a digital input pad that allows me to enter the temp, but I never tried anything higher than 125....
 
It's funny, but I brew very close to the tankless heater and it never occured to me to crank it temporarily and get much hotter water to star with in my HLT... heading to Home depot tonight to get some connectors to connect directly to my Hot output redirect valve.
 
Let us know how it does Randar..

I'd guess that my water coming in is around 50 degrees in the summer, so that would be a 130 degree temp rise to 180. I'll look into how it would handle that much of the swing.

The current tax rebate is a huge incentive, but to use it for mash water - now that is REALLY what's important..
 
honestly, even if it gets it to 145 or 150 I will be thrilled. Cut some time out of my HLT warm-up and save propane for later batches. I usually have mine set at 115 so this would definitely save me time and propane.
 
1. do you filter the water going into the heater? you might want to do that.

2. is your garage valve going to cut off the supply to the rest of the house? it should or someone might have a nasty shower surprise.

Number 2 is a fantastic idea. I'll install a valve that cuts the house when I crank up the heat.

I'm not so sure that #1 is too much of an issue for me.
 
Ok, so I checked it just now. I got 178 degrees out of the faucet and I didn't have to do anything to mine to get it into "overdrive".

But I would definitely not turn it that high if there was the threat of other folks in the house using it, 180 degrees is f'in HOT.

The way mine was installed I can actually throw a diverting valve and they open the port directly coming out of the heater, so I think that's what I will end up doing when I kick it into overdrive. Then I have to manually throw it back to bypass to feed back into the main plumbing system so I won't accidentally leave it on 180. You might ask you plumber to ensure there is such a bypass or a shut-off to the rest of the house for the times when you use this mode?
 
gig..giggidy..giggidy... gig..g

I heard of a production brewery who uses two in series to get the temps and flow that they need. Can't remember where I saw that.

Useless information.
 
you can install a tempering valve in the line going to the rest of the house set it for 120 deg or so and leave the heater cranked up for brewing....simmons is a brand that I have installed in hospitals and nursing homes
 
gig..giggidy..giggidy... gig..g

I heard of a production brewery who uses two in series to get the temps and flow that they need. Can't remember where I saw that.

Useless information.

Aurora CO's Dry Dock (2009 GABF Small Brewing Company of the Year winner) had this on their old system. Made Big Brew Days easy as they just ran a hose off it out back for all the homebrewers to use. Just set the desired strike temp and fill the MLT.
 
I had the same thought as I have a guy coming on Tuesday to install a tankless at my place. However, my hang up is how to filter. Here's the problem that I see. Adding a filter on the inlet would pretty much mean having a whole house filter which is expensive and pretty much useless for me since my water is really low in minerals. However, all the filters I have seen for hot water are sediment only. This means I would need a bypass valve on the cold water side that would re-direct through a filter when brewing along with the hot water bypass to the garage. I do not know if it is worth the cost. Any thoughts as far as that goes?
 
I use mine to brew but it only gets up to 140*. I have an outlet right off the heater and it doesn't get me to mash temps but really shortens the amount of propane/time that I need to get it up to temp.
 
Adding a filter on the inlet would pretty much mean having a whole house filter which is expensive and pretty much useless for me since my water is really low in minerals.

Then what are you trying to filter out? Do you have a water analysis?
 
Number 2 is a fantastic idea. I'll install a valve that cuts the house when I crank up the heat.

I'm not so sure that #1 is too much of an issue for me.

Soooo, were you able to get it up to 180 or not? What kind of flow rate did you see? Approx. what is your groud water temp?

I'm very interested in doing this for a 55 gallon set up. Having no HLT would be very nice for multiple reasons. So flow rate is improtant.
 
Just got it put in last week. No problem hitting 180 degees with a flow rate of 2.4 GPM. My ground water temp is 47 degrees. I only brew 5-6 gal batches, so I can collect my mash & sparge water in a few minutes.

One bummer: if you turn the heater up past 140, you can only set the temp in 10 degree increments, so 140, 150, 160, etc up to 180. I thought I'd be able to precisely set the temp desired, so that was a bit of a let-down.

here's a few pics..

For a brew op of that size (55 gal), I think you would need several tankless heaters in series. But it would be totally doable. Or, just use one and have a well-insulated liquor tank. My plumber who installed mine, said he uses his to fill his hot tub.

I'll brew my 1st batch on it this weekend. I'm interested to find out how the unit affects my brew day.

heater 4.jpg


Heater 2.jpg


Heater 1.jpg


Heater 3.jpg
 
Chlorine/chloramine (off top of my head I can't recall which they use)

Aren't those both driven off by the boil?

BTW - I did have a diverter valve installed. I can either supply hot water to my brew station OR the house - not both at the same time - to reduce the chance of scalding someone at a household fixture.
 
Aren't those both driven off by the boil?

BTW - I did have a diverter valve installed. I can either supply hot water to my brew station OR the house - not both at the same time - to reduce the chance of scalding someone at a household fixture.

You can't drive chloramine off by boiling like chlorine so that means one has to filter...sounds like a cold side house filter is what I would need.

Nice setup. I got mine installed last week, shipped with a broken part so I can only get a trickle of hot water. Guy has been giving me the run around on getting it fixed but promised to come by tonight with the replacement part. I miss warm showers...
 
Soooo, were you able to get it up to 180 or not? What kind of flow rate did you see? Approx. what is your groud water temp?

I'm very interested in doing this for a 55 gallon set up. Having no HLT would be very nice for multiple reasons. So flow rate is improtant.

I have been able to hit 180 with 45 degree ground water. Flow rate is ???? as I have not measured exactly.

I wouldn't trust the hot water heater to hit the EXACT temp you need for mash-in though... I would still have some kind of regulating tank.
 
What does one of these run, ballpark? And is it as obtrusive as it looks in the pic?

Awesome potential for homebrewers.
 
Obtrusive? Compared to a 75 gallon hot water heater the thing is tiny. If you look them up on line, the price varies by how many BTU's you want to put into it. Like 2k - 5k I think.
 
Just got it put in last week. No problem hitting 180 degees with a flow rate of 2.4 GPM. My ground water temp is 47 degrees. I only brew 5-6 gal batches, so I can collect my mash & sparge water in a few minutes.

One bummer: if you turn the heater up past 140, you can only set the temp in 10 degree increments, so 140, 150, 160, etc up to 180. I thought I'd be able to precisely set the temp desired, so that was a bit of a let-down.

That is a bummer that you can only go up in increments of 10. Looks like the guy did a very nice install. Good idea with the divert valve. I guess this is out of the question for replacing a HLT. Too bad....

Thanks for the pics and the response.

Edit: A thought, could you possibly by-pass the digital control and switch to a BTU output mode? Or I guess since it is natural gas you would really just be changing how much gas you are cranking into it, essentially controlling how open the gas valve is?
 
What does one of these run, ballpark? And is it as obtrusive as it looks in the pic?

Awesome potential for homebrewers.

The high end ones run around 2k + install costs but as with anything... you can spend as much as you want. You might also be able to find the higher end units through a dealer in your area or online and install yourself if you are a confident home improvement and DIY'er.

Not sure it makes sense for most folks unless they have an old hot water heater that needs replacing (like I did when I bought my house). Buy it for the whole house and get the homebrewing bonus as just that... a bonus. JMO

I got a $500 tax credit when I had mine installed and it takes up a LOT less space than my old tank (I now store a lot of brewing gear in the space the old tank was behind my furnace.
 
That is a bummer that you can only go up in increments of 10. Looks like the guy did a very nice install. Good idea with the divert valve. I guess this is out of the question for replacing a HLT. Too bad....

Not really, but the time you need to be using/heating the HLT is dramatically reduced. No inefficient propane usage or expensive electricity rates to bring
water up to mash or sparge temps.
 
Not really, but the time you need to be using/heating the HLT is dramatically reduced. No inefficient propane usage or expensive electricity rates to bring
water up to mash or sparge temps.


Yeah I mean i use my hot water heater to give me 120 degree water right now and it totally helps for both strike and sparge water. But yeah, looks like I can't get rid of the HLT all together unless I rig it up.
 
True, but my hotwater heater doesn't have 15 rows of lines running all over the place.

It only has gas and water in/out (and venting/intake which for most folks is tied to a flue in their traditional hot water heater setup). These are direct vent like high efficiency furnaces.
 
True, but my hotwater heater doesn't have 15 rows of lines running all over the place.

Don't get me wrong, I like the idea.

Like Randar said, it has the same number of in/outs as your current heater does except he has some extra piping and stuff to run it to his brew rig. I hear what youare saying tho, it looks like more, but I think thats becuase on a standard water heater, the take up vertical space more than wall space.
 
I also have a diverter valve, but I still have to remember to go hit the keypad back to normal temps.

So true. I have to do remember to do the same. I forgot to change it the other day.. luckily the wifey & little one were napping and i remembered..

Next addition: a "change it back to 120 dummy" sign to hang on the diverter valve..
 
I also have a diverter valve, but I still have to remember to go hit the keypad back to normal temps.

That's a good idea. I sometimes get in trouble from the mrs when I forget to change it back. I get in more trouble when she hops in the shower after I have it set at 90* for filling a carboy with hot water than for having it at my 140* max but at 180* that could cause some hurt.

You could also take a que from Brewmasters where they have the hot and cold line run in to a Y joint out with valves on each side. Keep the hot side at 180 and add enough cold water to bring the temp down to close to the correct temp. He keeps and eye on the thermometer while he is filling and adjusts the cold as needed.
 
a little o/t but im a plumber by trade, did he install any valves to flush out the heat exchanger of the heater? usually you have to flush out these things with vinegar every so often to kill the scale on the inside of the HE when they get scaled up they will throw an error code...
 
I have been able to hit 180 with 45 degree ground water. Flow rate is ???? as I have not measured exactly.

I wouldn't trust the hot water heater to hit the EXACT temp you need for mash-in though... I would still have some kind of regulating tank.

You have the Noritz right? Hold up & down arrow (on keypad) at the same time and you enter a list of service codes. Scroll with up arrow to 31 & it will tell you precisely the outgoing GPM's. It can tell you a bunch of other cool things too. I'll get the list and post what the codes are..

It can tell you the exact temp of the water leaving the hot water out. When I set my temp to 180 and ran it, there are moments when the heater has heated the water to 195+ - for brief moments, then it settles back to 180 on the nose.
 
a little o/t but im a plumber by trade, did he install any valves to flush out the heat exchanger of the heater? usually you have to flush out these things with vinegar every so often to kill the scale on the inside of the HE when they get scaled up they will throw an error code...

Mine has output valves right below the tank that I could use to backflush or the like as you note, but I have very very low mineral content water here with Lake Michigan water. I actually threw on QD's so I take my brewing water from as near the source as possible (and with the disconnect for the rest of the house engaged)

I don't see the same in the pictures above, but they could be hidden?
 
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