Budley Doright
Well-Known Member
Please keep us posted as to how it works out?
Well N A, The Tankless Water Heater is the Bomb!
- Thread starter legallyflying
- Start date
noob12345
Well-Known Member
I have a friend who is a gas engineer. He told me to not even bother water cooling it and just take heat exchanger out but I like the idea of water cooling. The unit will only run for 30sec at a time max. I'm guessing the low setting makes for an incomplete burn. I read somewhere to keep them around 50%. For the best burn. What equipment are you using to test? Don't doubt your results, just curious.
ttystikk
Well-Known Member
My buddy in the mountains had a hot tub shell sitting outside that he recirculated through the tankless heater. Worked great, even in summer; the unit doesn't care how warm the water is, just that it's flowing. After all, the flame is always going to be a lot hotter than the water.Ya I'm not sure either but the Navien's do and at low fire they produce the highest levels, like I said they are trying to get approvals to allow for higher CO levels, the limit in the US is 400 ppm air free. And yup I've never tested one in a sealed environment, the ones I do test bring combustion air in from outside so always 21% o2. Things can change re dirt on burner, flame impingement, spider webs on intake, that can spike the CO. I haven't searched but would love to see if the water cooled ones are CGA certified, the ones I did see did not have it as far as I saw. The other thing I don't get is how to get rid of the heat as it must take a huge res to do that.
If I was going to integrate such a system, I'd connect it to the hot water side.
ttystikk
Well-Known Member
The flame is much hotter than boiling, so even hot water will cool the unit and effectively remove excess heat from the room. Then, that heated water can be used elsewhere.
Budley Doright
Well-Known Member
They do not remove excess heat, they just don't add much but yes they add some due to the radiant heat from exposed pipes and the units heatexchanger. The unit does care what the water temp is. They monitor incoming water temp so if your temp setting is 160 and return temp is 160 it won't turn on. Im just saying you would need a pretty big heat sink to lower the temp of the return water to keep the thing running. Not sure how long or often these things need to cycle for to keep CO2 at required levels (room dependant) but that would dictate the amount of heat you would reject. The hot tub would heat up to say 110 then not fire again until it had to even with water flowing, it takes both to fire. And not sure what you mean connect to "the hot water side"?
Budley Doright
Well-Known Member
Take the heat exchanger out? They don't remove excess heat from anywhere and they work on flow and temp to reduce and increase gas flow to burner. Yes they would not add as much heat to your room as a open flame, they will still add a bit of heat just by the nature of a gas appliance in the room. I've actually given this some thought while drunk last night and by leaving the heater outside the room and piping exhaust in you eliminate the "low oxygen for combustion" scenario. Here is a letter from Navien tech
Budley Doright
Well-Known Member
We install mostly Navien, but Rinnai and bosch as well. I've not tested anything but Navien myself that I recall. I don't get out in the field a lot any more to test new installs and the crews do that. And don't get me wrong, I'm not saying it won't work but just to be extremely careful. And I don't think it would kill you if you had working CO monitors but you may find a dead grow room if the plants are exposed for any length of time .
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noob12345
Well-Known Member
Yes his idea was just to turn it back into a non water cooled co2 gen, by taking heat exchanger out and just re-wiring a switch to ignitor (turning it into a simple burner) probably easy enough to do but the water cooled idea sounds like a great idea, especially for summer time.
definitely correct (not about being drunk, thats bad
, 
.)trying to bodge up some sort of flue for those things wont be easy though...
Budley Doright
Well-Known Member
Well, there are lots of ways to make a CO2 burner that are easier than buying a tankless and removing the heat exchanger, gas engineer huh. A ventless room heater with o2 sensor would be an idea, $100 at princess auto lol. And it's acually quite easy to mount it on the opposite side of the grow room wall and vent it in 
. The Navien allows for like 30' of vent at 2" and longer for 3", not sure of the total but thinking 60', some others are the same.
. The Navien allows for like 30' of vent at 2" and longer for 3", not sure of the total but thinking 60', some others are the same.
noob12345
Well-Known Member
there maybe easier ways but not cheaper ones..... it would cost less than 60€ and not put out the same heat of a room heater, which seems like a pretty silly idea to me, considering the extra heat that thing is going to put out during summer and its certainly a lot cheaper than the co2 burners from the stores etc. You could do better than insulting by best mate, typical yank, knows better than everybody else...
When you tell someone what you have, they try and give you the best answer off the top of their head and then big heads like you come along and say insulting shit like "gas engineer huh"
When you tell someone what you have, they try and give you the best answer off the top of their head and then big heads like you come along and say insulting shit like "gas engineer huh"
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Budley Doright
Well-Known Member
First off I was referring to the fact you said take the heat exchanger out of a tankless, that is silly and not feasible, a "gas engineer" should know that. And once you do that, if you could, which you can't, are you not left with just a burner? You know, kinda like a regular CO2 burner. Fuck man really, it's a stupid fucking ideal. Second I'm not a Yank lol. don't have to be any nationality to tell someone their ideal won't work lol. As a gas whatever he shouldn't offer advice that is going waste you, his best mate, a pile of money without knowing what the fuck he's talking about. Not to mention he could kill you in the process. Carry on, I'm done trying to offer educated advice lol.
noob12345
Well-Known Member
if its "silly and not feasible" why has it already been done by lots of others?! search around and you will find several examples.......
Educated advice - "And once you do that, if you could, which you can't" (nice advice by the way), is complete bollox, ive looked at the design myself, it takes like 5 mins to take out the internals and bin the water side of things,connect flow switch to co2 controller etc. Yes you are just left with a burner, which still costs a lot less than off the shelf non water cooled co2 generator. Just admit that your full of shit and know FA!
Educated advice - "And once you do that, if you could, which you can't" (nice advice by the way), is complete bollox, ive looked at the design myself, it takes like 5 mins to take out the internals and bin the water side of things,connect flow switch to co2 controller etc. Yes you are just left with a burner, which still costs a lot less than off the shelf non water cooled co2 generator. Just admit that your full of shit and know FA!
Budley Doright
Well-Known Member
Lol ok ya I should have looked at the cheap piece of crap your talking about lol. Good luck with that as far as keeping heat out of your room, fuck me, that's your tankless huh. It's a camp water heater and may perhaps drop the exhaust temp from about 400F to 390F, a high effeceincy tankless exhaust is 90f ... fucking idiot. So let's review shall we..... first this thread is about tankless water heaters, not camp heaters you attach a garden hose to. Second please tell me how that is cheaper or better than the heater that actually has a low O2 sensor that I suggested and please use examples as I have. Your a little kid that doesn't know shit. Ya I'm gonna stick around just to watch this, please keep us posted, love to see how this works for ya lol.
noob12345
Well-Known Member
ummmm learn how to read...I said i was keeping the water cooling and that removing it was an "idea". So now your basically trying to tell me that a simple burner will put out as much heat as a room heater?! Also an LPG camp water heater and an LPG tankless water heater = THE SAME FUCKING THING DICKHEAD! Maybe I am an idiot but then what does that make you? I imagine you look in the mirror and see some sort of genius right? Do everyone a favour and take another look! BTW you if you really read though this post you would realise that I will have exact same setup as OP! Are you going to tell him his idea is shit aswell?!
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ttystikk
Well-Known Member
The OP used a kiddie pool inside the building. Remember that the device is being used to add CO2 to an enclosed space, not to heat the water to a given temperature, so it doesn't take as much heat shedding as you might think to support it.
My dual circuit chiller has a hot and a cold water circulation system. If I were to use one, I'd connect the CO2 burner to the hot side so the cogenerated heat could be routed and used elsewhere.
ttystikk
Well-Known Member
This conversation went downhill, sorry to see that.
'Never argue with an idiot; they'll drag you down to their level and beat you with experience'. -Sam Clements, aka Mark Twain.
Let's try to stay above the infighting.
The unit sold by Advanced Nutrients was simply a rebranded small capacity tankless water heater with a battery powered ignitor and a flow switch. The CO2 controller would actually operate a pump, which would kick the unit on and run until the CO2 level reaches the desired setting, then shut the pump off.
It might be a camp heater. It was sold with an 'ice cap' additional heat exchange device that by the accounts I heard did a good job of extracting heat from the exhaust.
I agree that the space would need occasional ventilation to keep any undesirable byproducts from building up.
ttystikk
Well-Known Member
@Budley Doright
There are already commercial scale greenhouses doing something I find even more fascinating; natural gas electrical power generation, and BOTH the cogenerated heat and CO2 are both utilised in the facility. The video I saw was not specific about the heat exchange system. In this way, all of the products of combustion are utilised, maximising efficiency.
I think this definitely represents a big part of the future of greenhouse operations, especially in winter. I doubt such a system could provide for all the electrical requirements of an indoor growing facility, but it could provide all the great, all the CO2 and at least a substantial fraction of the power needs.
There are already commercial scale greenhouses doing something I find even more fascinating; natural gas electrical power generation, and BOTH the cogenerated heat and CO2 are both utilised in the facility. The video I saw was not specific about the heat exchange system. In this way, all of the products of combustion are utilised, maximising efficiency.
I think this definitely represents a big part of the future of greenhouse operations, especially in winter. I doubt such a system could provide for all the electrical requirements of an indoor growing facility, but it could provide all the great, all the CO2 and at least a substantial fraction of the power needs.
Budley Doright
Well-Known Member
We have moved to localized cogeneration here for both power and heat generation with little plants popping up everywhere. Your right about things moving forward, unfortunately at my age I doubt I'll be involved much lol. The provincial government, for the first time in 35 years is reintroducing rebates for geothermal which should boost the industry. I see huge benefits to the industry using that technology as well. I actually have approached one of the bigger producers about doing an audit of their facilities, no word yet
. I wonder about carbon tax on these producers and how that will effect things? It's going to get interesting here in the next while as the whole country legalizes, although the government is positioning to become the sole distributor, almost cartel like lol.
Budley Doright
Well-Known Member
Ya my fault lol. Got caught up in the moment lol. I've put him on ignore so not to continue an argument I won't or have no desire to win. He needs to try it as I should I guess, just don't see it removing a whole lot of heat since the exhaust will still be in the 350-400 range, oh well
. I've been trying to be good but I drank a bottle of takillya on Friday and perhaps got a bit cranky the next few days lol, all better now . I did think my ideal of piping exhaust into grow (condensing unit) was good though lol.