Announcement

Collapse
No announcement yet.

Tankless heaters to heat HLT (pump issue?)

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #16
    Mt: We keep the HLT at 185, the max for our Rinnais--or I should say we try to.

    The Rinnai C199 also has the internal restriction valve.
    Timm Turrentine

    Brewerywright,
    Terminal Gravity Brewing,
    Enterprise. Oregon.

    Comment


    • #17
      Originally posted by TonyT View Post
      Our HLT is not pressurized, it's open to ambient. I've got a couple factory tech contacts, I'll dig them up and PM them to you. I think our biggest hurdle in setting the thing up was getting out of the mindset of "I'll have a big tank of 185F water" and into the mindset of "I'll have a big tank of water that my heaters can get up to 185 as I need it"
      We use Takagi in our brewhoue and have grown to love them. This comment really resonated with me. Once we entered this state of mind, the heater found a new place on the brew day.

      Comment


      • #18
        Revisiting this post:

        Due to our mash-in procedure, we need a lot of hot liquor at mash-in. Using the Rinnais to heat the water going into the mash tun didn't work, as the max. flow possible is less than 10 gpm each, going down as the delta T goes up, with a flow of only ~2 gpm when heating 45F tap water to 180F.

        I re-plumbed the HLT so that we can either heat the entire contents of the HLT by recirc through the three Rinnai C199s, or heat the make-up water through the Rinnais as it goes into the HLT. When we're warming up our cast-back water from the HX (about 160F), it's reasonable fast to heat it by recirc, and when we need make-up water, we have enough time for the Rinnais to keep up. The night before a brewday, we fill the entire 1,200 gal HLT with cold water and have all night to heat it up. After the first castback, we're just heating the castback water.

        Our hard water is still a major issue. I clean the strainers on the Rinnais a couple of times a day, and acid-wash the units every two weeks. I expect this frequent cleaning regime to significantly shorten the lifespan of the HXs in the Rinnais. I'm using inhibited sulfomic acid @ ~pH 2-3 for the acid wash, as it seems, based on the color of the cleaning solution afterwards, to erode the copper elements of the system less than phos acid or the recommended distilled vinegar--which is also very expensive.

        Thanks for all the feedback and discussion.
        Last edited by TGTimm; 03-06-2018, 10:05 AM.
        Timm Turrentine

        Brewerywright,
        Terminal Gravity Brewing,
        Enterprise. Oregon.

        Comment


        • #19
          Steam?

          Why wouldn't you use your steam utility? Would be superior technique and likely cheaper to operate.
          Phillip Kelm--Palau Brewing Company Manager--

          Comment


          • #20
            This all feels very familiar. We're in the process of starting up. The last roadblock in this process has turned out to be the exact Rinnais you seem to have purchased for your brewery. The sales rep promised that it could deliver 10gpm, which is pretty much all i'm seeing through our city 1'' cold line anyways. We purchased 2 units to do this job. Upon turning them on we are seeing more of a flow rate of ~5gpm, which is so slow that I cannot blend cold water slow enough to hit any sort of adequate strike temp. When I set the units to their lowest setting they run about 9-10gpm, so I know they are capable of pushing water through at the flow rate I need. We had purchased a water tank with the idea that it was going to be a recaptured water from knock out tank, water that could be redirected back to the Rinnais. Unfortunately it now looks as if this water tank is going to be turned into our permanent HLT, installed with a float, using one of the Rinnais to keep it at 150F and the other Rinnai to pass through on the way to heating said water up to 185F. I'm a little skeptical how this plan is going to work out as the initial plan backfired on us a bit.

            TGTimm, you mentioned how often you have to clean these things, which makes me even more worried. The sales rep did mention to us that distilled vinegar should be recirculated through them quarterly at most, but it sound like you've needed to do that much more. Nothing was even mentioned to me about a strainer, maybe I need to get on a ladder and figure out where that would be and how often I should expect to deal with cleaning it out. Is it essentially a filter for the units? We also have fairly hard water where I'm located.

            Comment


            • #21
              Question for you guys recirculating into the HLT - What kind of pumps are you using to move the water? I'm guessing something around 3/4 - 1 HP, but am more curious if you're using a full on sanitary grade pump, or something a little bit cheaper since its just being used for hot water.

              Cheers
              Manuel

              Comment


              • #22
                Had some trouble posting a bit ago.

                Bez--Your sales rep is selling you a line of bull. Our sales rep told us the same, and I designed the system around this number, much to my chagrin. Consult the delta T/throughput chart in the Rinnai C199 instructions. 10 gpm is possible if not heating the water. Going from our line temp of ~50F to 185, we get about 2-2.5 gpm. Recircing our castback water at ~160 going to 185, we get around 6 gpm. This is with everything perfectly clean.

                Mounting the units where you need a ladder to access them is a mistake. There is a little bitty thimble-sized strainer just below the cold in port, on the valve manifold. We clean ours at least daily, and I need to do ours right now--again. Our water is about 130ppm carbonate hardness.

                Manuel--We're currently T'ing off our main HL pump for the recirc. IIRC, a C100 pump with 1.5 hp would pretty well meet the needs of a Rinnai C199, but we get better throughput with the over size pump--and likely accelerated erosion of the internal HXs.
                Last edited by TGTimm; 04-03-2018, 03:45 PM.
                Timm Turrentine

                Brewerywright,
                Terminal Gravity Brewing,
                Enterprise. Oregon.

                Comment

                Working...
                X