Tankless Water Heaters - Pros/Cons

[mobiledynamics]

I recall looking it. It was not the price....but there were cons to replacing to tankless when I looked at it. I can't recall but it was something like hot water temp surges, etc. I was walking into this knowing maintenance would be required.


Anyhow, who's got a tankless.
Any cons ?

I need to start the homework again.

 

[tshetter]

I do not have one but I have heard there is about a 30sec delay to get hot water, depending on application/install.

IE, if you have a central tankless for the home, it takes 10-20 seconds to warm up the water flow and another 10-15sec for the flow to reach the shower.

When we finally build our new house, I think we will go the tankless route. Not sure if there is a benefit to central/distributed tankless or not. I have worked in many industrial environments that have small 230v tankless in the restrooms and they give almost instant hot water.

Hopefully there are some better answers. I'd love to know more about them and their application/installation suggestions.

 

[James-W]

Here is a link to a website that explains the pros and cons.

http://www.apartmenttherapy.com/pros-and-cons-of-a-tankless-water-heater-176538

 

[maxspeed96ct]

I recall looking it. It was not the price....but there were cons to replacing to tankless when I looked at it. I can't recall but it was something like hot water temp surges, etc. I was walking into this knowing maintenance would be required.


Anyhow, who's got a tankless.
Any cons ?

I need to start the homework again.

Just keep in mind you get what you pay for, dont but the cheapest one out there and expect the best.

I installed a rinnai tankless in my previous condo.

PROS -
-saved me about 30-40 a month switching to a N/gas tankless from a 40 gal electric
- Freed up alot of space
- Constant hot water, always at a steady temp unless someone opened another hot faucet while you were showering ( but i think it happens with any water heater )

CONS
- You have to wait an addition 3-4 seconds for the hot water compared to a normal storage type water heater
-Hope to god the thing never breaks, cause I consider myself a good mechanic , I work in the HVAC related trade and I damm sure wouldnt want to work on the thing. It looks like a oversized high tech watch inside
-The cost compared to a normal water heater is more then double


Now at my new home I have a typical 40 gal nat gas water heater . And even after owning a tankless before , If my current 40 gal water heater craps out, im not sure if id buy another tank less.

 

[vhol5]

I have one. Natural gas.
I don't know if I would do it again though. I don't think I'll see any cost savings, since it's just three people in the house. Our gas bill in the summer is just $14, the minimum, so no change there.

I do like the endless supply of hot water though. Very well regulated. When someone is running the hot water, you can listen to the blower, increasing and decreasing, to regulate the temperature. Kind of like a fan on a charcoal grill, more air, hotter flame.

One of the biggest downsides, is the increase in time to wait for the water to come up to temperature once you turn on the water. If it's a long run, it seems to take forever! When it used to take about 20 seconds with a tank, it now takes about 30! Not significant, but noticeable.

Only time will tell how long it lasts, but its rated for 15 years.

We have electric ones at work, which seem to work well ONLY is it's a short run from heater to faucet. Otherwise it's useless.

 

[maxspeed96ct]

One thing you need to consider that you didnt mention is what source of fuel do you have available? oil? propane? nat gas or elect?

 

[encantofred]

i am thinking about putting one in my new shop that will have a bathroom. so, the shower and sinks would be within 10' of the heater. do they give enough hot water to take long shower? (if sized properly?)

tom

 

[mobiledynamics]

Ah. I remember now. The *surge* that I mentioned in my post was just that. It's great for backtoback showers, if not tub. The issue for me was the delay. If I recall, if just *using the faucet to wash hands* throughout the day, it was much more noticable than a traditional tank

 

[vhol5]

i am thinking about putting one in my new shop that will have a bathroom. so, the shower and sinks would be within 10' of the heater. do they give enough hot water to take long shower? (if sized properly?)

tom

You can take as long a shower as you want! The supply is endless. Hot baths for my grandaughter, even after everyone has showered!

Thats the good part...

 

[Highbeam]

You can take as long a shower as you want! The supply is endless. Hot baths for my grandaughter, even after everyone has showered!

Thats the good part...

It's also the bad part. There is the potential for abuse, long showers, wasteful habits, etc.

 

[mygarageone]

Tankless units are great when they work , when they need service , most heating & plumbing people won' service them even if they install them.
Lastly do not buy one from a box store if you can. Avoid it.

Over all , I would'nt put one in my house and I do this stuff for a profession .

 

[mobiledynamics]

MGE:

Plumber by trade ? Rheem or Bradford in that case. In looking at the heights, by going from a 50 to 75, in both brands, it looks like I should be OKAY with height of the vent. +++1 for me is that a 4" is already in place.

 

[Fuego]

I have a tankless nat. gas in my current home and are generally happy with it. We built the house and I wanted the garage space back that would have be taken up by a tank heater. It does take a few extra seconds to get the hot water to the shower/faucet but then it's endless. In a previous home we took out two 50 gal tank heaters and replaced them with a single Rinnai "hybrid" heater that had a small 2-3 gal tank for relatively instant hot water. It also had a small pump w/ a timer and a x-over between the hot and cold side under a sink in our master bath (farthest end of the system). The timer would kick the pump on just prior to our topical morning shower time and that made hot water nearly instantaneous. Having had tanks, tankless, and the tankless "hybrid" systems I can say I prefer the hybrid over the others.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

 

[maxspeed96ct]

I have a tankless nat. gas in my current home and are generally happy with it. We built the house and I wanted the garage space back that would have be taken up by a tank heater. It does take a few extra seconds to get the hot water to the shower/faucet but then it's endless. In a previous home we took out two 50 gal tank heaters and replaced them with a single Rinnai "hybrid" heater that had a small 2-3 gal tank for relatively instant hot water. It also had a small pump w/ a timer and a x-over between the hot and cold side under a sink in our master bath (farthest end of the system). The timer would kick the pump on just prior to our topical morning shower time and that made hot water nearly instantaneous. Having had tanks, tankless, and the tankless "hybrid" systems I can say I prefer the hybrid over the others.

Sent from my SAMSUNG-SGH-I337 using Tapatalk

Yes I had a rinnai but not a hybrid, the hybrid is great . the small storage tanks makes all the difference, the rinnai hybrid is really the best you can get with a tankless .

But the cost kills it for me, you could buy 5 regular nat gas water heaters for the cost of it.

A lot to consider

 

[MoparMarv]

I was told at more than 2 people in the house there is no gas savings compared good typical water heater. I am considering one as my old heater it's getting up there. When I inquired at my local plumbing supply they were not talking them up like they were the best thing ever and the guy even had one in his house. And nearly everyone I have talked to said do your research, pay up and buy the best. Cheaping out will cost you in the end. I'm no expert but that's what I found when I was asking around.

 

[Ross/Kzoo]

I've had a nat gas one for the last 7 years. I don't know if they've solved the problem yet but I get a "cold water sandwich". After I dialed it down some it helped but there is still the sandwich.

 

[Randy in Maine]

I would never go back to a tank style water heater. I had a propane Rinnai for about 5 years and loved it compared to my 40 gallon electric. Saved me $50 a month. Never had an issue with it. When I added the radiant floor heat, I had to get a tankless unit that allowed for the hot water heat.

The only "con" I know of is if you are using hard water (like from a well). Everyone told me to buy a Rinnai as opposed to a box store unit as they are more serviceable if you should ever need it.

 

[mygarageone]

Tankless units are great when they work , when they need service , most heating & plumbing people won' service them even if they install them.
Lastly do not buy one from a box store if you can. Avoid it.

Over all , I would'nt put one in my house and I do this stuff for a profession .

Either one ,they are both good . How ever B W is the highest rated one. But they are sold only to plumbers.

 

[Tunajoe]

I bought 6 tankless water heaters over the years.
Everything from Navien, Bosch, Noritz, and some Japanese brand I can't remember the name of.
15 years ago I thought they were the next great thing.
You have to have adequate gas supply. My first one I had to get a new natural gas meter and run a new line because the tankless required it.
Check your gas requirements for the unit your looking at.
Make sure your water isn't "hard". You'll build up a bunch of scale and it will eventually stop working. They sell flushing valves and kits. Make sure you install one.
In my new house I installed two Noritz. They seem to be working great so far. I figure when one breaks down, I'll have another to use till the other is fixed.
The fellow that said they were like a watch inside and difficult to work on was exactly right!
Wen they break down, you'll be out of hot water till you buy a new one or fix it.
Very few guys know how to repair them

 

[nsnrider]

we have a basic natural gas tankless at the shop. bought it from one of the big box stores. Very simple, doesn't even need power. Easy to install and has worked great for almost 10 years now. The only service it needs is cleaning the metal screen on the gas line by the pilot for the air intake, takes less than a minute to do.

We have been very happy with it. There is a delay with hot water but you get used to it. Ours is installed next to the bathroom so its not bad at all.

I have a tankless at home that is build into the oil fired boiled. I absolutely love it. I never worry about running out of water even after the kids have taken showers I know I will have plenty of hot water.

When time comes to replace my tenants hot water heater, I'm planning to go with a tankless. I like simple designs, it might not have the bells and whistles but it is a breeze to work on.

 

[Speed-Racer]

We have had a bosch tankless water heater for the last 8 years. It takes a little longer for the water to heat up. You can feel the temp change if someone turns on hot water at another faucet while you are in the shower. You need to check the spec for the gas pipe line and the exhaust pipe is larger(5in or 7in) than the 3in typical on a tank style hot water heater. You will spend more on parts to have it installed. The advantage of unlimited hot water and lower monthly cost is hard to beat.

 

[anthony666]

You need to check the spec for the gas pipe line and the exhaust pipe is larger(5in or 7in) than the 3in typical on a tank style hot water heater. You will spend more on parts to have it installed. The advantage of unlimited hot water and lower monthly cost is hard to beat.

that's not true anymore sir, the new navians for example have positive pres gas valves which means they use a 1/2" gas pipe and the exhaust is 2" pvc

http://www.navienamerica.com/Product/Category-NPE-A Series/

all the other companies new models will be the same or better

the lag is the only real downside, you can loop into a small holding tank and draw from that, but storage kind of defeats the purpose of using a tankless in the first place

 

[bugnout]

I've had a Natural Gas Takagi TK-1 for 8 years now. Had it installed when I had my furnace replaced. New furnace exhausts out the side of the house via PVC pipe, Tankless HW heater uses the old flue. I have had one issue with it. The pressure switch that senses that the exhaust is open was flaky. I tried to find a replacement part, but weeks of looking and calling service places was unfruitful. It is an adjustable part that had the adjustment screw sealed from the factory. I ended up breaking the seal and readjusted it to solve the problem.

I love it! A short wait for hot water is small price for endless hot water. The TK-1 is sized for two consumers, meaning, you can be doing a load of laundry while your taking a shower or two showers going at the same time. I can tell when someone has turned on a faucet somewhere in the house only by the slight drop in water pressure. No change in temp.

 

[mygarageone]

I've had a Natural Gas Takagi TK-1 for 8 years now. Had it installed when I had my furnace replaced. New furnace exhausts out the side of the house via PVC pipe, Tankless HW heater uses the old flue. I have had one issue with it. The pressure switch that senses that the exhaust is open was flaky. I tried to find a replacement part, but weeks of looking and calling service places was unfruitful. It is an adjustable part that had the adjustment screw sealed from the factory. I ended up breaking the seal and readjusted it to solve the problem.

I love it! A short wait for hot water is small price for endless hot water. The TK-1 is sized for two consumers, meaning, you can be doing a load of laundry while your taking a shower or two showers going at the same time. I can tell when someone has turned on a faucet somewhere in the house only by the slight drop in water pressure. No change in temp.

I personally believe Takagi makes the best one out there. I installed on for a friend yrs ago like 8 yrs ago and haven't heard a word from him since.

It was not my choice but he wanted an on demand unit so I installed it.

 

[anthony666]

I installed on for a friend yrs ago like 8 yrs ago and haven't heard a word from him since.

what a ****** friend !!! you'd think he'd at least call and say thanks, maybe buy you a few beers

 

[Streetbu]

Just keep in mind you get what you pay for, dont but the cheapest one out there and expect the best.

I installed a rinnai tankless in my previous condo.

PROS -
-saved me about 30-40 a month switching to a N/gas tankless from a 40 gal electric
- Freed up alot of space
- Constant hot water, always at a steady temp unless someone opened another hot faucet while you were showering ( but i think it happens with any water heater )

CONS
- You have to wait an addition 3-4 seconds for the hot water compared to a normal storage type water heater
-Hope to god the thing never breaks, cause I consider myself a good mechanic , I work in the HVAC related trade and I damm sure wouldnt want to work on the thing. It looks like a oversized high tech watch inside
-The cost compared to a normal water heater is more then double


Now at my new home I have a typical 40 gal nat gas water heater . And even after owning a tankless before , If my current 40 gal water heater craps out, im not sure if id buy another tank less.

Pretty much agree with everything except....steady temp water ONLY if your on public water. If your on a well the temp varies up and down with water pressure. Ideally you'd want to install a pressure regulator on the out out of your holding/pressure tank to keep the the water pressure constant. Alos exhaust venting is expensive and usually must be ordered, most places don't carry it in stock.