| Author | Message | ||
     Scottorious |
So I just bought a house and I am going to dive into some major renovations. The entire second "half" story needs to be re-done. and a major roadblock is the original chimney. The only thing the chimney is used for now is the water heater. I want to tear down the chimney and replace the existing water heater with a tankless on demand style. I just wonder if any of you have any good experience and have seen any good deals around. I am looking for a unit that actually senses incoming water temp because I would like to build a solar water heater that would feed directly into the water heater. So something that can adjust the heat according to incoming water temp is needed. | ||
| Blake |
I talked to our plumber about installing one when our conventional tank unit gave up a few years back. There's a lot more to installing tankless than I thought. His advice was go with an outdoors unit as the exhaust fan is noisy, not something you want to hear every time you run hot water. He also recommended one for each wet area of the house, for us that was just two, bathroom and then kitchen/laundry. It was going to be WAY more expensive than replacing the gas fired conventional unit, so we stayed with that. I have one of those instant hot water taps on the sink though. | ||
| Pwnzor |
My brother has a tankless. Takes forever to get hot water to actually come out of the faucet. Once it does, it keeps coming. That said, he wishes now that he had gone with a conventional unit. To me, the tank represents an additional fresh water supply in an emergency. | ||
| Pwnzor |
Blake, I know you're addicted to making instantly hot beverages and cup o noodles, right? LOVE my instant hot faucet! | ||
| Trojan |
Tankless or 'combi' boilers are great for small apartments or houses, but can't cope with the demands of a large(ish) house or family. As most US houses I have seen fall into what I would call the 'OMG that is huge' category I don't think a tankless design would be man enough. We recently had to have a new boiler/heater fitted into our relatively small (by US standards) house and went with a traditional tank design on the advice of various plumbers and engineers. Even this doesn't give out the heat we used to get with our old fashioned boiler, but it is supposed to be more energy efficient (we'll see!) | ||
| Kenm123t |
Your problem with tankless systems is the same issue your having with tanked systems If you want warm water at quickly at the point of use with out useing multiple heaters you need a recirculation system. Noritz has recirculating system diagrams in thier engineering manuals as most of the tankless companies. Tankless isnt the problem its your plumber. We use a tank disconnected for storage of heat reclaimed water from the Hvac unit free heat which then is fed thru the tankless heater to the house if the water is warm enough the tankless never comes on if the temp drops below set point the heater starts staging on Noritz heater s have 14 stages of control. Tankless works well if set up properly You guys need new plumbers Trojan in extreme weather the new Eu heaters freeze up their vents and shut down they are a condenseing type burner also the EU limited the max temp sorry its buried in software you may be able to hack it by running it as a space heating system Scott I have built many large 32 -52 panel solar water heater arrays 1200-2000gal storage with tankless heater back up it works In Ill an indirect system may be needed look at the Florida Solar Energy Center to find the Solar heating hours in Ill may not be worth the cost to build (Message edited by kenm123t on December 21, 2011) | ||
| Fahren |
Tankless is an excellent option, especially if a) you are away from home a fair amount and don't want to spend to keep water warm while away; b) you will have a solar HW first system, which would probably have an indirect storage tank anyway (no vent needed, just a stainless tank with heat exchanger). The Rinnai (gas) or Seisco (electric) tankless, on demand units act as "pass-through" units, the incoming water is only heated if the temps are too low. You will spend more up front, but with a solar heating system, you will reap very good benefits for hot water heating operating costs. | ||
| Xl1200r |
The only thing the chimney is used for now is the water heater. It's not used for anything else? What kind of heat do you have? For the record, my old hot wanter heater hung for 19+ years. When it crapped, I looked into tankless for no other reason than the energy savings, and decided that for the amount of time I planned on living in that house and the amount of hot water we use (only two adults living there), it would take too long for it to pay off. Trojan - I'd bet my house doesn't fall into the "OMG that's huge!" category! I have a whopping 1150 sq. ft! | ||
| Blake |
Matt (Pwnzor), All kinds of goodness happens when steaming hot water is available instantly at the sink.  Geez Matt (Trojan), it's not necessarily the size of the house, but rather the amount of hot water that is used, so it's family size, shower head design/flow rate, and shower habits that govern how much hot water capacity is required. There are household tankless heaters that can provide scalding hot water at 5 GPM; that's a lot of hot water! But like our plumber advised, it's most desirable to install a separate tankless heater for each wet region of a house. Sounds like the enviro-nazis have taken over defining and apportioning hot water in the EU. You might benefit from a low flow shower head. We're still free to set the temperature and capacity of our water heaters here in Texas. I went with a 50 gallon (gas fired) unit for our one bath home. We've never run it out even though I keep the temperature set at just 120oF. One key to efficiency is to ensure the hot pipe is insulated well. especially as it exits the heater. The type of heater (tank versus tankless) doesn't affect lag time for hot water to emerge at the faucet either so much. Rather, that's governed by the plumbing, size of the pipes (bigger dia requires more water to warm up), length of pipe running from the heater (longer pipes take longer to warm up), type of pipe (PVC vs copper, where copper takes longer to warm up), and whether or not it's insulated (non-insulated takes longer to warm up and cools down much more quickly, duh ) . Interesting info from the internet... For homes that use 41 gallons or less of hot water daily, Tankless Water Heaters can be 24% – 34% more energy efficient than conventional storage tank water heaters. They can be 8% – 14% more energy efficient for homes that use a lot of hot water, around 86 gallons per day. You can achieve an even greater energy savings of 27% – 50% if you install a Tankless Water Heater at each hot water outlet. | ||
| Wolfridgerider |
Just a FYI, Drain your hot water heater every now and then. If you are on a well you should do it once a year. My home is not even 10 years old and I had to replace the hot water heater already. My new one has been in for about 2 years. With all the rain we have been having my well needed new grout. This put a BUNCH of crude into my water system. My wife decided it would be a good idea to drain the hot water heater... something about brown/orange water she didn't like... whatever... Needless to say... the amount of "stuff" that came out of the tank was AMAZING to me. Draining the tank at least once a year is now on my Honey Do list.... | ||
| Hootowl |
As much as I'd like to take a three hour hot shower, it isn't worth the money. Efficiency is irrelevant. It costs me $5 a month to run my conventional 80 gallon gas fired water heater. The only reason I would ever install a tankless is to recover some floor space in the garage. | ||
| Pammy |
I've had both. I saved exactly zero dollars on using the tankless. It cost me huge money to have it installed. Twice as much as conventional for the unit itself....Not worth it. I switched back to a conventional. I run a timer on my water heater. It doesn't do much while I'm away. | ||
| Hammer71 |
http://www.eztankless.com/ got me one of these not too long ago, installed it myself to save an assload of cash. Takes a bit to get the kitchen water scalding hot but all other faucets are just a tad longer than with the tank. | ||
| Kenm123t |
120 f is too low to prevent legionella growth in your tank set your heater to 140 and install point of use tempering valves | ||
| Hootowl |
is this an issue if you're on chlorinated municipal water, or only with wells? | ||
| Sleez |
typically running a tankless will cost you much more in fuel costs. the BTU rating of the avg tankless is well over 100K. the avg conventional water heater is around 35 to 50 KBTU. in addition, having the ability to use as much water as you want, ends up using much more water, now you can take an hour long shower, wash clothes endlessly etc. we only recommend tankless for small households, one or two people. at least as far as energy use is involved. if that isn't an issue, than most work well for many years. your best bet for energy savings are the newer hybrid heaters; 2.35 energy factor!!! http://www.geappliances.com/heat-pump-hot-water-he ater/electric-water-heater-features.htm | ||
| Wolfridgerider |
That's pretty cool... wish it wasn't a GE product. | ||
| Fast1075 |
If you have an older central air system and (A) Run the A/C system fairly cool. (B) Have a system with an efficiency lower than 12.00 SEER. You can save on your energy costs by installing a heat recovery unit. If you set your thermostat at 80, don't waste your time or money. The unit will not have enough run time to do much work. It all depends on your usage habits and equipment efficiency. | ||
| Chauly |
Heat Recovery, 31 years ago... http://tinyurl.com/c4elbgq (scroll two pages back for the beginning of the article) | ||
| Blake |
I should clarify Ken, the water is 120F coming out of the faucet. I don't know what it is inside the tank. Probably not 140F though. Wolf, Draining the tank may not help. When advising me on a replacement for the 25 year old Rheem water heater, our plumber shared that none of the current consumer model conventional hot water heaters will last much if any beyond ten years, no matter what. The old ones were much better quality tanks, less efficient, but much more durable. If you still decide to drain the tank periodically, be careful to avoid busting the valve at the tank drain. Seen it happen, and when inspecting the one on | ||
| Wolfridgerider |
My drain is built out of durable plastic.... lol.... LOL!! | ||
| Blake |
Mine too!  | ||
| Kenm123t |
Chlorine is outgased as the water is heated and rises to the top of the heater its also oxidizes the particulate in the water depending on the dwell time in the tank you may have a big petri dish in your heater. new fixtures are tempering any way so raise up the temp and live safer. Fast in so fla we use heat recovery more dads 17 seer 2 stage system heats 85% of his hot water needs 1st stage is 18k btus. The building Im in right now has no heat even with electronic ballasts. We are in cooling pretty much 24/7 The new GE hybid is w/h is nice but pricey nice for your garage nice dehumidifier side benefit | ||
| Pammy |
Ken, the electrician that hooked up the water heater in one of our shop buildings set the temp so low it smelled like sewage coming out of the tap. I thought it was the wonderful Pinellas Park water so I called them. They told me just what you said and sure enough the problem was corrected. I had to let the hot water run for a looooong time to let the funk out. Pee Yew! | ||
| Buellish |
I have been thinking about installing a manifold at the hot water heater.And running pex to the individual taps to reduce lag time. | ||
| Kenm123t |
Buellish look up a maniblock system for PEX nice system and you can shut off each fixture individualy fron the manifold | ||
| Scottorious |
I do believe there will be enough solar energy to make it worthwhile. I have researched a couple diy solar projects at the website build it solar and found some home brew ideas for around 1000 dollars. I have gas heat for the house but its a direct vent model that no longer needs the chimney. I would possibly think about leaving the existing water heater but the chimney takes up too much room in the second story and it needs to go. So in comes in tankless hot water heater fed by a supply of solar heated water. 90 percent of the hot water used is during the hours of 5 pm and 6 pm when my roommate and I get off work. So it makes sense that If the sun can heat up a good portion of the water during the day and as a backup the tankless kicks in, it should save enough money to make it worthwhile. In combination with low flow heads which run at 1.5 GPM I could get by with the smallest of units. I have seen some models that you can run in combination with another. So when the family grows I could in theory add another water heater if need be. | ||
| Scottorious |
Ken yes I agree that an "indirect" system would be used. I am thinking that I would use a drain back model, controlled by a differential controller. When the heat of the panel was warmer than the water in the storage tank it would turn a circulation pump on. when the panel cooled off the pump would shut down and the water would drain back into the storage tank. | ||
| Cyclonedon |
it it was me, I'd go with the tankless but the real cost is in the stainless steel exhaust vent pipe required for those but you will end up saving money down the road with a tankless water heater. | ||
| Trojan |
Geez Matt (Trojan), it's not necessarily the size of the house, but rather the amount of hot water that is used, so it's family size, shower head design/flow rate, and shower habits that govern how much hot water capacity is required. My assumption was that bigger houses tend to have more people and a larger requirment for hot water. However even in my house where there are only two of us we were recommended not to get a 'combi' or tankless system, but to stick with a 'tanked' condensing boiler (the only alternative to the combi type of boilers we can now buy over here thanks to EU bully rules!) | ||
| Davefl |
I do not have a tankless but I am very happy with my GE Hybrid Water heater.. It does make noise but mine is in the garage. | ||
| 1313 |
I don't know if this details has been mentioned yet. If it has been, disregard. I researched the ones that another division of the company I work for makes when my parents had to replace their water heater a few years ago. There were some unusual (electrical) power requirements that would've ended up making it cost prohibitive to get a tankless water heater. My parents new conventional water heater has been fine ever since installation, FWIW... 1313 | ||
| Chauly |
My $.02 has to do with a tankless setup I installed in our small restaurant. As you can imagine, the hot water requirements are wide-ranging, from just washing hands to filling sinks. The way I covered both bases is by having a 10-gallon electric underneath the main handwash sink (and right behind the mop sink, next to the dishwashing sinks. Did I mention it was a small restaurant?:-) The tankless is a Bosch, and it requires no power at all: it has a small water turbine that fires the igniter when the water flows. The 10-gallon temp is set fairly high, and provides instantaneous hot water. By the time you get through 10-gallons of hot water, the tankless has caught up and maintains the flow for sink-filling duties. Best of both worlds... |
