Well N A, The Tankless Water Heater is the Bomb!

If it helps anyone I've been running with my res tank in the room for almost 2 months and its not getting hot at all. It doesgetprettywarm by the end of a 12hour cycle but is cools right off by the time it runs again, but i keep the room at 84 lights on and 68 lights off

Duke, your running propane right? If your running propane you can probably offset any radiant Rez heat by blowing a fan On the propane tank. The liquid to gas reaction is endothermic so it will absorb heat. Blowing air on the tank could maximize this cooling effect ( or at least the dispersion of cool air)

My concern with getting too hot is that my room is 10X20X7 with 2,400 watts of lights. I'm afraid a single garbage can of water will be heated up too hot by continuous usage and not have much chance to cool down since it will be located on a second floor in summer. I will have an ac unit running, but still the ambient temperature in the room will be 85* and it will be heated up every time the burner comes on.

My water heater is close to the ducting I want to run in and it has a capped end. The NG line runs to a T, one leg then goes to my hot water heater and one is capped. Would it simply be easier to add the set up on the right side of the picture rather than trying to actually cut in and place a T above the hot water heater where I have space restrictions? I would need a couple extra elbows, and probably 6-7' of vertical pipe, and maybe 6' of horizontal pipe to get to the area where I would ideally install a T, but then I wouldn't have to deal with cutting into a pipe and refitting it for a T. I could just measure everything, get it all cut and threaded at the store, then install it myself by only removing a cap.

I can't really understand looking at the photo but I will say this... In terms of unscrewing threaded pipe. You can't just unscrew the section you want to replace with something. cause when you grab on and twist it, one end loosens and the other end tightens. If you cut into the pipe that would not be such a big deal as you could cut in and install a T but you will end up "rebuilding" (taking everything apart and putting it back together again), everything downstream of the T you just installed. If that seems like a bummer, then you would install a union. A union is just something that allows you to take the pipes apart and put them back together without actually twisting the pipes.

Another option that may be worth it is to just run flexible gas line. It is a tad bit more expensive and you will have to get it from a plumbing supply store but it is sooo easy to run. just uncoil and install. Something like this....http://cgi.ebay.com/gas-Flex-1-2-tubing-pipe-KIT-33ft-2-fittings-10376P1-/250810864412?pt=LH_DefaultDomain_0&hash=item3a657e131c

With some determination, a hole saw, a wiring snake, and a jar of vaseline you could probably snake that right through an interior wall.

The pipe on the left side of the drawing (on the bottom) terminates in a cap. I have a capped gasline pointing at the ground next to my water heater, immediately after it tees off and feeds into the water heater. I assume this cap, like all other caps i've encountered, simply screws and unscrews on the pipe it's connected on. The second portion (right side) of the drawing would be brand new piping I would install in place of that cap. It would essentially run parallel but in the opposite direction of the main feed for about 6-7 feet vertically, then another 6' horizontally. From that point the plan will be the same whether I run this new piping or install a tee on the main feed.

The main feed at that location is semi blocked by a wall that is 3' away from the basement wall giving restricted access to the straight run of the pipe. The actual portion of the pipe with threads on it is further hidden behind a bathroom that was added on after the gas line was in place, so the threads are totally inaccessible. It was my understanding that I needed to cut into a length of pipe, then unthread both sections, and replace when it's been fitted with a tee. Having such limited space around the pipe requiring the cut, and no access to the threaded portion seems like it will take a relatively straight forward job and make it difficult. I'm unsure how I would even accomplish this, hence me thinking it might be cheaper and easier to just connect to the tee at the water heater and run an additional 14' of pipe with a few elbows.

For all that hassle and work it might be worthwhile to go flexible tubing. I was under the impression that you could not get access to it and it had to be installed by a professional though.

legallyflying said:

With some determination, a hole saw, a wiring snake, and a jar of vaseline you could probably snake that right through an interior wall.

Click to expand...

I'm pretty sure i'm just going to disconnect the vent from the furnace system and use the vent as a conduit since I also need to run water and a drain. I won't require water, drain, or gas when this room is no longer the grow room, so I can remove all the lines easily too and reconnect the furnace when i'm done.

Yeah, much much easier to just start the new piping from the exiting cap. take the cap off, shut your gas off, then install a 1/4 turn valve. THen you can turn your gas back on and take your time installing it. If your setup allows, I would probably bend (smash) the vent a little and just run your lines adjacent to the vent rather than in them for a number of different reasons I won't get into.

The flexible line regulations are kind of weird. its like a scuba. you don't NEED a padi license to go diving but you can't get a tank refilled without one...On two separate occasions I have walked into a plumbing store and purchased corugated SS gas line. the first time they said nothing, the second time they started this whole "ummm, you need to have a certification to install this, not sure if we can sell it to you". I said "you sold it to me 6 months ago....". the manager came out, looked at me, and said yeah, ok no problem.

It's not rocket science to install that tubing but it does take some understanding and concentration to install the fittings on the end of the pipe in a manner that they are not going to leak. Its this weird compression type of fitting where little sleeves fit in the grooves of the corrugated pipe and then as you tighten the fitting, the end of the tube gets pushed into the joint and it seals. Basically you have to use a hack saw and make a straight smooth cut through the pipe in order for it to seal properly. took me several tries the first time but the other times it went off without a hitch.

Probably best to just use black steel pipe to get the line to the point where it is going to go upstairs and then go flexible line from there.

Got a ?, maybe its been talked about, or just an off the wall ?. i was inspired by your design and was thinking. I have a conventional natural gas hot water tank, would it be as simple as running the exhaust from that into my grow room?? Something tells me no but wanted to see what you thought about it. i dont think it would be a good idea, no idea what other stuff is being released like carbon monoxide and what not.

The biggest issue is that you can't control the output. I think I already addressed this actually. When you start fucking with the ducting on gas appliances you change the venting efficiency. This can cause issues with burner performance, perhaps to the extent that you start producing CO.

Read my earlier post about element concentrations in gas appliances. Virtually no CO

Ghost214 said:

Got a ?, maybe its been talked about, or just an off the wall ?. i was inspired by your design and was thinking. I have a conventional natural gas hot water tank, would it be as simple as running the exhaust from that into my grow room?? Something tells me no but wanted to see what you thought about it. i dont think it would be a good idea, no idea what other stuff is being released like carbon monoxide and what not.

Click to expand...

Likely cheaper in the long run to just use a heater. If you're in a unique situation, are handy and creative, it can and has been done. You still need a controller and a couple of 24V actuated dampers. When you need Co2 your hot water heater will need to be runnng so you may need a valve to drain some water to make it fire.

thanks for the info. i think there are better options out there for me, maybe more expensive, but at least it will be right(I know that is a matter of opinion, dont really think there is a right or wrong way with a lot of things). But seriously thank you to everyone on here that is willing to help people out. I know that when i can help, i will!!

So how much has your gas bill gone up since you've been running this?

Hard to tell because it's winter time and I have gas heat. Maybe $20...maybe. Put it this way, it hasn't been any higher than last years bills. NG is damn cheap. Waaaaaaay cheaper than propane.

Even running propane it's lots less than compressed co2. I go through almost 3 bottles of compressed @ 20.ea per cycle a 5lb tank of propane used to last me 2-3 cycles.

agreeed with budley i can get 10-12 weeks of 12/12 out of a propane tank

Natural gas is mostly methane which is CH4. It is priced by the thousand cubic feet for usually around $11 for residential. 1,000 cubic feet gives you 44.6 lbs of natural gas.

(35.31 cubic feet in 1 cubic meter
1000 Liters in 1 cubic meter
one mole of gas at ideal conditions occupies 22.4 L
Methane has a molecular weight of 16
453.6 grams per pound.)

One methane molecule gives you one co2 molecule. The molecular wt of methane and co2 are 16 and 44 respectively. So every unit of natural gas turns into 44/16 units of co2.

44.6 lbs of NG (for about $11) turns into 122.6 lbs of CO2

Propane is C3H8 with a molecular wt of 44 and turns into 3 CO2 molecules each at 44. So each unit of propane turns into 3 units of CO2. 122.6 lbs of CO2 would require 40.87 lbs of propane, or about 2 normal bbq tank fulls (probably $30-40).

122.6 lbs of CO2 would require 122.6 lbs of compressed CO2, or about 6 tank fulls from a 20-lb tank. No idea what a 20 lb fill up of CO2 costs but its probably a lot more than $2.

Nicely done!! A 20lb co2 tank costs $16 in the city to refill. So its safe to say that NG burner is 800% cheaper than bottled Co2?

For those staring blankly at the screen and your NG bill. You probably see cost per therm. A therm is equal to 100 cubic feet. Incognito, you must live near me as my gas is 1.15 per therm. Pretty damn close to your $11 per 1,000 cubic feet estimate.

I just looked up the average cost in the usa. I don't even receive hard copies of my gas bill, it gets automatically billed. I see the charge every month in my email, but i'm not even sure of the units I get charged in. I don't think you could say it's 800% cheaper; wouldn't 100% cheaper be $0? But you could say bottled is about 800% more expensive to run compared with NG.

I'm going to set this thing up real soon. Should pay for itself within the first month.

Well Fuck yeah again!
Up and running tonight!
Ill post a pic or two later when I wake up.
I seem to be cycling more often than you guys. About every 5 minutes between pump/gen on/off. Is that ok or should I lower monitor for more overshoot/longer cycle? Overshoot is minimal (1540) and my digigro telaire is mounted as high as the gen exhaust but opposite side room. Run time is less than 2 minutes until off at 1500ppm.
Temps are running 85ish with dehumid at 50%.
Way stoked!
Thanks LF and also Budley for the advice.

You could go for a little more overshoot and reduce cycle times. probably 6 of one half dozen of another. It would cycle less but stay on a little longer. Your temps humidity sound good so maybe just try it and see what heppens. Sounds pretty dialed though. Glad to share the stoke. They are pretty pimp. Now you can throw your cylinder out the window