Tankless Water Heater & Mash Temp

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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.

Cool! I never bothered reading the manual... :drunk:
 
What does one of these run, ballpark? And is it as obtrusive as it looks in the pic?

Awesome potential for homebrewers.

Its roughly 9"D x 28"H x 20"W - without the plumbing of course. It takes up considerably less space than my old 50 gal water tank. The new tankless take up a few square feet, while the old tank took up cubic vertical feet.

My pal is a plumber so he cut me a great deal & I assisted with the install. These units are around $1500, without installation. In a typical situation that would probably add another 1,000-1,500.

Pricey yes, BUT, my local gas co is offering a $200 cash rebate for these units. The Govt ran a 30% of invoice tax rebate until Dec 31 2010, which is approx $800 for me. My old water tank is nearing the end of life at 6 years old & that would have cost me $700-900 for an install. So it started to get cost effective & logical when I realized the brewing potential.

Plus, these units have a 20+ year lifespan.
 
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....QUOTE]

But really, by the time i'm pouring 180 degree water into my cold mash tun (cooler) and it preheats for a few minutes, I'm guessing I'll be right around my 12-14 degree above mash-in target temp. Or if not, a couple splashes of cold water should do the trick.

This also means instant mash-out & sparge water. Yes - the HLT, for me, is dead.
 
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...

Yeah, he installed an isolator valve kit for this purpose. Although, our water is so soft here, there isn't hardly any scale issue.
 
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.

I have had a Navien direct vent TWH for a couple of years. My setup does not resemble yours (I run double-walled copper in and as I direct vent out from the basement to the outside above).

Interesting idea about using this to pre-heat your water prior to the boil. How many BTU's are you using to get the water from 45' to 180 to 220' via the TWH versus taking 120' water and getting it up to 220' (+100') on the stove? Are you using natural gas or propane (I use propane). Montanaandy
 
Plus, these units have a 20+ year lifespan.[/QUOTE]

Not if you are running them that high they won't (assuming you have a recirc pump involved in your system). Montanaandy
 
I have had a Navien direct vent TWH for a couple of years. My setup does not resemble yours (I run double-walled copper in and as I direct vent out from the basement to the outside above).

Interesting idea about using this to pre-heat your water prior to the boil. How many BTU's are you using to get the water from 45' to 180 to 220' via the TWH versus taking 120' water and getting it up to 220' (+100') on the stove? Are you using natural gas or propane (I use propane). Montanaandy

Its a 199,000 BTU Nat Gas unit, so I would assume that when I run it at 180 degrees, its using close to all of that. All built-in efficiency of the unit is out the window when running it wide open I'm sure. Its probably eating gas like a monster.

After run off, I boil with electric. No BTU's there.
 
IThese units are around $1500, without installation. In a typical situation that would probably add another 1,000-1,500.

Pricey yes, BUT, my local gas co is offering a $200 cash rebate for these units. The Govt ran a 30% of invoice tax rebate until Dec 31 2010, which is approx $800 for me.

Not bad considering I just paid $500 for a 50 gallon gas heater, my old one lasted a whopping 5 years. Plus nat gas here is dropping like a rock, hmmm...
 
Plus, these units have a 20+ year lifespan.

Not if you are running them that high they won't (assuming you have a recirc pump involved in your system). Montanaandy

My parents have 2 Bosch tankless heaters that are 22 years old and have been running at 140 degree output for that entire time in a house of 5 people for more than half that time. A few minor part replacements is it and this is "older" technology.

Nobody here is suggesting running at 180 all the time, BTW, and yes, they last longer than that without issue, generally, as long as your water doesn't have high mineral content. If it does, it just takes a more regular maintenance cycle to ensure there isn't too much build-up.
 
I have had a Navien direct vent TWH for a couple of years. My setup does not resemble yours (I run double-walled copper in and as I direct vent out from the basement to the outside above).

Interesting idea about using this to pre-heat your water prior to the boil. How many BTU's are you using to get the water from 45' to 180 to 220' via the TWH versus taking 120' water and getting it up to 220' (+100') on the stove? Are you using natural gas or propane (I use propane). Montanaandy

first of all, i have to use propane to heat the water if I don't use the tankless, so the "per BTU" cost of propane tanks is many times that of NG for me. Yeah, I could tap into my NG and will eventually, but for now the cost difference is significant.

Secondly, the Noritz is generally rated ~83% efficient. Meanwhile, a traditional electric stove element is ~70% and open flame NG is less than 60% IIRC and I am sure even less than that the way we use it with big flames, outside, and larger vertical columns of water (heat loss through walls and open surface of water with evaporation)...

I don't think I would be overstating that it would be a dramatic reduction in actual gas usage to get the water to that temp even running "full out". I haven't done the math but I doubt the difference in efficiency between heating 7 gpm @75 degree temp rise (all of these higher end units rated comfortably for a similar gpm flow) and 135 degree temp rise at 2.5 gpm, I don't think you're going from 83% efficiency to something silly like 60% (which would be the required drop to even bring this usage scenario's efficiency into question)
 
I had the Navien Condensing unit installed at 98% efficiency, given the efficiency of a open propane burner the tankless route is sure to save money on brewing.

JKnapp, I'm still stuck on the water filtration issue. Since I live in the area we have pretty much the same water supply so I would be interested to hear what your results are without filtering the water. I want this to work for me, but can't get over the spector of chloro-phenols.
 
first of all, i have to use propane to heat the water if I don't use the tankless, so the "per BTU" cost of propane tanks is many times that of NG for me. Yeah, I could tap into my NG and will eventually, but for now the cost difference is significant.

Secondly, the Noritz is generally rated ~83% efficient. Meanwhile, a traditional electric stove element is ~70% and open flame NG is less than 60% IIRC and I am sure even less than that the way we use it with big flames, outside, and larger vertical columns of water (heat loss through walls and open surface of water with evaporation)...

I don't think I would be overstating that it would be a dramatic reduction in actual gas usage to get the water to that temp even running "full out". I haven't done the math but I doubt the difference in efficiency between heating 7 gpm @75 degree temp rise (all of these higher end units rated comfortably for a similar gpm flow) and 135 degree temp rise at 2.5 gpm, I don't think you're going from 83% efficiency to something silly like 60% (which would be the required drop to even bring this usage scenario's efficiency into question)

I'll find out for us Randar. One of the service codes tells you the percent efficient while the unit is in running. Brilliant technology I tell ya.
 
I had the Navien Condensing unit installed at 98% efficiency, given the efficiency of a open propane burner the tankless route is sure to save money on brewing.

JKnapp, I'm still stuck on the water filtration issue. Since I live in the area we have pretty much the same water supply so I would be interested to hear what your results are without filtering the water. I want this to work for me, but can't get over the spector of chloro-phenols.

I'll let you know, but for the record, I never filtered any of my water before. In previous batches, I never used hot water from my tank water heater to avoid potential sediment, etc - I only used from the cold line. So.. the only difference with the tankless is the cold water is super-heated before I get working with it. I can't think it'll be much different. I guess all my previous batches had chloro-phenols in them and they tasted pretty good!
 
I had the Navien Condensing unit installed at 98% efficiency, given the efficiency of a open propane burner the tankless route is sure to save money on brewing.

Just checked out those models. Holy-moly. More like a 2-stage furnace than previous tankless models. A lot of "newer" technology in there but much more efficient. My folks are building their retirement home "green" so this looks perfect for them. I had never heard of them so they must be relatively newer on the market since last I looked in detail was ~4 years ago.
 
I'll find out for us Randar. One of the service codes tells you the percent efficient while the unit is in running. Brilliant technology I tell ya.

I meant to ask you as well, when you measured 2.4 gpm at 180, was that out of the 3/4" valve or through a fixture that might restrict flow. 2.4 gpm sounds a lot like a possible laundry sink flow rate (w/o a flow restrictor). I did notice some "pulsing" in the flow when I have the valve wide open and temp set to 180. It must have been dialing back the flow to allow the heater to keep up, but I was connected right to the 3/4" valve with a 5/8" ID hose, so there were really next to zero restriction on the flow rate I was requesting.
 
Just checked out those models. Holy-moly. More like a 2-stage furnace than previous tankless models. A lot of "newer" technology in there but much more efficient. My folks are building their retirement home "green" so this looks perfect for them. I had never heard of them so they must be relatively newer on the market since last I looked in detail was ~4 years ago.

Yeah, its an impressive unit, supposed to handle 4 showers at the same time...of course I only have two. Sounds like a jet firing up when it goes full bore, but other than that I'm digging it...supposed to be really reliable too. I think the only downfall with these things is that there is more lag time to get hot water than a tank as it has to fire up and start heating, but they do make some sort of small tank system to help with that I believe.
 
I'll let you know, but for the record, I never filtered any of my water before. In previous batches, I never used hot water from my tank water heater to avoid potential sediment, etc - I only used from the cold line. So.. the only difference with the tankless is the cold water is super-heated before I get working with it. I can't think it'll be much different. I guess all my previous batches had chloro-phenols in them and they tasted pretty good!

Yup, this is gonna bug me, the thought of the time and money savings of shorter brew days and fewer trips to fill propane is ringing in my head. I'm going to have to do a batch with tap water now to see if it causes flavor problems, I've been filtering for so long I can't remember if it made a difference with our Seattle water.
 
Yeah, its an impressive unit, supposed to handle 4 showers at the same time...of course I only have two. Sounds like a jet firing up when it goes full bore, but other than that I'm digging it...supposed to be really reliable too. I think the only downfall with these things is that there is more lag time to get hot water than a tank as it has to fire up and start heating, but they do make some sort of small tank system to help with that I believe.

Yeah, the recirculating option (it actually does the recirculation internally with a far-side hot water return inlet and small buffer tank) seems to be a more tightly coupled option than others I have seen.

But if you are simply comparing to a tank? First of all, you can put a tankless in a much more confined space so you can locate it more centrally (to reduce the longest run) if you wish to do so. Secondly, even if you're simply replacing the current tank, we measured only a 4-5 second increase in "time to hot" at our furthest run.

Mine can be loud running full bore as well. Definitely not silent, but it's int he basement next to the furnace (which also is not silent) so you can insulate the area for sound if you care about that sort of thing.
 
I meant to ask you as well, when you measured 2.4 gpm at 180, was that out of the 3/4" valve or through a fixture that might restrict flow. 2.4 gpm sounds a lot like a possible laundry sink flow rate (w/o a flow restrictor). I did notice some "pulsing" in the flow when I have the valve wide open and temp set to 180. It must have been dialing back the flow to allow the heater to keep up, but I was connected right to the 3/4" valve with a 5/8" ID hose, so there were really next to zero restriction on the flow rate I was requesting.

The 2.4 gal reading was from the unit service code for GPM output, while it was putting out 180 degree water.. The hot line comes out of the unit to 3/4" copper, runs about 10 feet, then reduces to a 1/2" stainless valve/barb. Its an UNrestricted output.

So, the tankless was giving me that reading. As the unit cranked up to 180, the volume/pressure significantly reduced from around 8 GPM to 2.4 GPM. If you tell it you want 180 degree water, the flow reducer adjusts output.
 
JKnapp, I'm still stuck on the water filtration issue. Since I live in the area we have pretty much the same water supply so I would be interested to hear what your results are without filtering the water. I want this to work for me, but can't get over the spector of chloro-phenols.

I'm no plumber but couldn't you put some kind of Y valve on the input side of the heater and have one of the branches have a somewhat cheapo water filter (mine cost $17 at home depot and filters sediment and chlorine/chloramine) so that you can put water through the filter only when you are making beer and not filter it otherwise?
 
Here are some service codes for Noritz heaters. I'm only going to list the ones that seem to be applicable to hombrewers:

Hold up & down arrows at the same time to access service codes

14 - Total GPM output of unit
15 - GPM of H20 going through Heat Exchanger
18 - % of capacity of the unit
30 - Temp of H20 IN
31 - Temp of H20 OUT
 
Very nice. I will have to give those a try next time I am dumping 180 with my frigid 45 degree ground water.
 
So will you be filling a gallon jug or some other container to measure your mash-out and sparge water.

I guess this is also directed towards Jknapp.

I got an old S.E.T.S. tankless water heater from my neighbor and am trying to figure out how to best use it. It would be awesome to replace my HLT with it but filling a pitcher to measure water kind of reduces the cool factor a bit.
 
I guess this is also directed towards Jknapp.

I got an old S.E.T.S. tankless water heater from my neighbor and am trying to figure out how to best use it. It would be awesome to replace my HLT with it but filling a pitcher to measure water kind of reduces the cool factor a bit.


Just run it from a hose into a HLT with a siteglass?
 
I'm no plumber but couldn't you put some kind of Y valve on the input side of the heater and have one of the branches have a somewhat cheapo water filter (mine cost $17 at home depot and filters sediment and chlorine/chloramine) so that you can put water through the filter only when you are making beer and not filter it otherwise?

I've thought about that. First I'm going to side by side water treated by filter and water treated with campden only to see if there is a flavor difference. My water is so clean that I think the campden approach will end up being the winner due to ease.
 
Very nice. I will have to give those a try next time I am dumping 180 with my frigid 45 degree ground water.

My test was with 47 degree ground water. You'll be just fine with your Noritz.
 
I think using these tankless hot water heaters for a brewery is a good idea but I think I would want mine dedicated. I cringe to think of what would happen if you accidentally left it set very high. It sounds like a scald waiting to happen unless there is something I am not seeing.
 
My parents have 2 Bosch tankless heaters that are 22 years old and have been running at 140 degree output for that entire time in a house of 5 people for more than half that time. A few minor part replacements is it and this is "older" technology.

Nobody here is suggesting running at 180 all the time, BTW, and yes, they last longer than that without issue, generally, as long as your water doesn't have high mineral content. If it does, it just takes a more regular maintenance cycle to ensure there isn't too much build-up.

Unless you have a recirc pump either internally in the TWH (which is usually a small HP pump) or preferably externally (a 3 HP is good) you will bleed off a good deal of water getting from 45' to 180' as well as energy to heat that water that is going down the drain. The energy savings if any is negligible. Montanaandy.
 
Unless you have a recirc pump either internally in the TWH (which is usually a small HP pump) or preferably externally (a 3 HP is good) you will bleed off a good deal of water getting from 45' to 180' as well as energy to heat that water that is going down the drain. The energy savings if any is negligible. Montanaandy.

Sorry if I have added any confusion. I (or anyone else) was not talking about generating 180 degree water in anything but a completely diverted mode to dump the water directly from the tank. God forbid anyone tries to recirculate 180 degree water, that's insane.

As for the recirc pumps, some models actually use March pumps in the same 1/25th HP range! 3 HP would be WAY overkill for low flow rate recirculation (unless you live at the Vanderbilt Mansion)

The Navien models have the hot water return to the tank from the far end loop and use that for maintaining a "hot water" temp in the hot water supply line (so you'd be wanting to insulate your hot water pipes) but it takes advantage of the 3-stage burner and bypasses the cold water inlet to re-heat the water already in the hot water pipes.
 
Just thought I'd give a quick report on brewing yesterday with the tankless..

I brewed a 5.25 gal batch of Pale Ale. It was great! From pre-heating my mash tun to srubbing the kettle - 3hrs 21mins - start to completely finished. Not that I want to rush through my hobby, but with a 14 week old at home, I don't get much time away..

I only used the Noritz unit at 170 for the mash in. After a prelim test, I realized that I probably didn't need the higher 180 range to start. I opened the unit up at 170 and completely filled my mash tun cooler. After 5-10 mins of preheat time, I ran off the water to the level I needed. I was a little low in temp at that point (around 160), so I added my fill hose and opened the valve on both the hot water & cooler, letting some of the cooler water drain while filling with hot water. Kind of like a pre-heat-fly-sparge. When it came up to 165, I shut both off & mashed-in. easy.

I collected my 1st runnings as usual, determined the volume I needed for my boil volume, set the Noritz to 180 and filled a measured HDPE container to transfer to my MLT. Adding the sparge water, the grain/mash bed measured 168 degrees - which was perfect.

Everything else was the same. The added bonus was being able to wash my gear in the driveway in 40 degree weather with 120 degree water.

I really like the added funtionality of a tankless water heater. If you're at a place where you probably have to replace your tank water heater, I'd strongly reccommend making this investment in your home & your brewery.

Now, if I could only get a trench drain installed in my garage.. hmm..
 
Maybe this has already been said but everybody is saying they are using the tankless water heater to get sparge water but why cant you use it directly to recirculate the wort for your different temperature schedules?
 
Maybe this has already been said but everybody is saying they are using the tankless water heater to get sparge water but why cant you use it directly to recirculate the wort for your different temperature schedules?

Huh?

I am guessing you are implying taking a 180 degree feed from the TWH to heat wort you are recirculating in the mash tun, right? In essence an old school counterflow chiller but in reverse...hot water in the outer jacket and cooler wort in the inner tubing (same can be said of a plate chiller which is actually a plate heater exchanger).

If that was you implication it seems an aweful waste of hot water unless you are using it for other purposes after it has raised the temperature of the wort. Theoretically you could use it for washing the fermentor, etc but I never have that much stuff to wash until after I have sparged.

I love tankless water heaters...always have even when I just had an in-shower water heater in my appartment in Cologne (student housing for 3 month language course...no other hot water in the flat). Electric tankless water heaters could theoretically be used as well but you better have a massive amount of amperage left in your service panel (many use 40 amp double breakers so 40 amp 220V)...and I am not sure they can be overriden to supply water in excess of 140 degrees.

Edit: Doh! did not notice that this was an ancient thread...sorry to revive a dead topic.
 
I think the implication was actually running wort from your mash through the tankless water heater and back into the mash tun to control mash temperatures. Much like a RIMS system instead of a HERMS
 
I think the implication was actually running wort from your mash through the tankless water heater and back into the mash tun to control mash temperatures. Much like a RIMS system instead of a HERMS

That'd be the worst of both worlds, expensive and difficult to maintain. Easier to stick an element in a tube, a pid in a box, and some wires between.
 
That'd be the worst of both worlds, expensive and difficult to maintain. Easier to stick an element in a tube, a pid in a box, and some wires between.

Strangely enough what brought me to this post was I was researching a way to speed up ramp temps... from what I understand is the RIMS tube will step up, but at the rate in which it does it may not be ideal... if this is instant than all that is required is pushing the volume through at it's max flow rate

my concern there is compacting the grain bed trying to move the liquid that fast

not to mention the cost of a TWH
 
Strangely enough what brought me to this post was I was researching a way to speed up ramp temps... from what I understand is the RIMS tube will step up, but at the rate in which it does it may not be ideal... if this is instant than all that is required is pushing the volume through at it's max flow rate

my concern there is compacting the grain bed trying to move the liquid that fast

not to mention the cost of a TWH

I figure the only way you are going to get truly fast ramp times is by adding boiling water. If a professional brewery isn't doing that, than anything we do at a homebrew level (RIMS, HERMS, and such) is going to be faster than their ramp times so it doesn't bother me much anymore.

I'm sure you could size a tankless to a pump speed for the compaction issue; but, then it would take a long time to raise the temp. Perhaps direct steam injection would get you what you want.
 
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