joey48442 PowerDork
4/26/20 9:05 p.m.

Does my title bother you?  It should


i was asking for opinions on replacing my old water heater, or going with a tankless on demand system?  Two of live here, but we tank longer than we should showers. Any experience with savings or not?



Dr. Hess (Forum Supporter)
Dr. Hess (Forum Supporter) MegaDork
4/26/20 9:13 p.m.

Go get a new one at Lowe's.  Put it in. Save half of a challenge car over hiring it out.

Grizz UberDork
4/26/20 9:16 p.m.

Gas? Electric? Tankless? A 55 gallon drum with a roaring fire in the back yard?

frenchyd PowerDork
4/26/20 9:49 p.m.

In reply to Dr. Hess (Forum Supporter) :

Currently operating cost of gas makes them a better deal than electric.  The exception is when natural gas isn't available. 

The most efficient is a tankless water heater but it's slightly more complex to install. 
It's not just brands but models. That is a really loaded question because not all models are available everyplace. 

Finally I'll assume you intend to buy it and install it yourself. If you feel challenged by that and plan on having it installed, that's not how it works.  
The plumber has a relationship with a distributor and that's what you will get. 

stuart in mn
stuart in mn MegaDork
4/26/20 10:02 p.m.

Either this is a test to see if anyone catches that "hot" is redundant, or you need to provide a lot more information before anyone can provide advice.  

joey48442 PowerDork
4/26/20 10:07 p.m.

Ha ha ha!!!  Somehow my entire post except rhe joke part disappeared!


i was asking for opinions on replacing my old water heater, or going with a tankless on demand system?  Two of live here, but we tank longer than we should showers. Any experience with savings or not?



carczar_84 Reader
4/26/20 10:17 p.m.

Edit: just saw your update, guess my tips are super relevant. Maybe they'll help on the general tip side, haha!!

Just replaced one at my sister-in-law's house a few weekends ago, so I'll give you my take for what it's worth.

  • Go to one of the box home stores and buy the one with the longest warranty period. The difference in price on a gas, 50gal tank was minimal (~$700 vs $770)
  • Depending on your install location, and how much space you have to work with may determine which box store you choose. The install I did had some pretty tight height limitations, so that determined which store we went to. The blue store heater was 2" taller and that was a deal breaker.
  • If you don't already have an expansion/surge tank, and your house has a water meter with a backflow valve, you'll need to install one. No very hard, but packaging in in your install space can be a fun game of Tetris. Tip: buy a few different lengths of threaded pipes and fittings to get he best packaging, return the rest. Save the extra trips during the current situation.
  • If you're not comfortable with sweating copper, shark bite fittings can be your friend. 
  • Do it yourself and save a few thousand. They were quoted $2800-3200, all in (tank, fittings, expansion tank, tax, etc.) we were under 1k.
jmthunderbirdturbo HalfDork
4/26/20 10:19 p.m.

I have an all electric tank-less, the 27Kw version. I love it, but there are drawbacks. I'll keep it simple.


1. Never run out (biggest Pro, most obvious). Wifey can take a 2 hour shower, Kids can fill a 60 gallon tub, and 30 seconds later I can have the same shower I always take and its piping hot. 

2. Space. Mine is the size of a 90's PC tower. It's stuck on the wall behind the clothes dryer and unless I'm changing the inlet filter, I forget its there. The old 80GAL tank I had took up what felt like 20sq ft of space...

3. Easy to install. I'm no genius, but I bought the breakers, ran the wire, and piped it up in a day. The most effort was removing the old one, as it weighed 200lbs.

4. Ease of replacement. If it dies, I can change it out in under an hour with pliers and a screwdriver.

5. Cost. You only pay for the water you use. So if you travel a lot, or often shower elsewhere (I used to shower at work frequently, for example), you can save real money as you only heat what you dispense.


1. Flow. With these units, especially the electric ones, you have a maximum GPM at any given temperature delta it can handle. So you have to be careful. Yes, you can get as much hot water as you want, but only so much per minute. This means not starting the dishwasher and clothes washer *while* wifey takes her 2 hour shower... basically, for the one we have, as long as no one is washing their body, anything goes. During shower/bath time, you have to be mindful. I have heard the gas ones have more BTU/higher delta, which makes sense, but I don't have any experience with those.

2. Initial cost. Mine was $400, plus about $400 in parts. I needed (4) 30A breakers, 100ft of 12/3 with ground, 3 sticks of PVC, a new particulate filter, etc. Gas ones are more costly in every way unless your a tradesman who can make deals and do the gas/exhaust work.

3. Delay. With tanks, you get water in however long it takes for it to flow from the tank to your dispense. Tankless have to warm up, and It's quick, but not 'now' quick. Electric is faster, as soon as the flow trigger is set, the 3 zones kick on and heat the micro-coils and I can feel the pipe on the outlet getting hot in 3-4 seconds. The gas ones are a bit slower, I'm told. This delay equals a touch of water waste, if that bothers you, and a touch of irritation if your wanting to wash up in hot water at the furthest sink from the heater. It takes time.


Let me know if you have any more questions. 




RevRico PowerDork
4/26/20 10:30 p.m.

In reply to carczar_84 :

I've never needed an expansion/surge tank before, but it seems like I might need one at the new house. 

Can I get a $2 summary of what to look for/where it goes?

joey48442 PowerDork
4/26/20 10:39 p.m.

In reply to jmthunderbirdturbo :

Wow!!!  Great info!  When you switched to the tankless, I assume it was from a gas water heater?  Did you notice a total difference in monthly energy cost?  Less gas but more electricity?



Grizz UberDork
4/26/20 10:40 p.m.

In reply to RevRico :

A tank on the supply line, usually close to the heater.

carczar_84 Reader
4/26/20 11:04 p.m.

In reply to RevRico :

Grizz covered the basics. With the water meter in place, as the water heats and expands it has nowhere to go now that it can't "push" back to the supply side. We just installed a tee off the cold supply side of tank, a section of pipe and an elbow to the expansion tank. You'll also need to set the expansion tank air bladder pressure to match your typical water pressure at your house. You can get a pressure gauge for a few bucks at the box store and the tank is pressurized with a standard schrader valve.

jmthunderbirdturbo HalfDork
4/27/20 1:12 a.m.

In reply to joey48442 :

No, I have no gas at my place, just power. We are out in farmlandvilleplace Ohio, so we're on well and maintain our own Aeration system for septic. Old unit was a GE 80Gal, *3 element* behemoth, that was not leaking, but so full of scale we couldn't empty it (at least 20%). 

We did notice a drop in power consumption, but we also did a lot of other mitigating around then, too. LED bulbs, replacement windows, new multi-speed furnace blower, etc. I would do the swap again, no question. 


joey48442 PowerDork
4/27/20 6:21 a.m.

In reply to carczar_84 :  thanks!  Makes sense I think I'll be doing some measuring before I go to the store!


stuart in mn
stuart in mn MegaDork
4/27/20 11:29 a.m.

Electrical capacity is probably the biggest issue - as mentioned above, four 30 amp breakers (for a total of 120 amps) is often required, so you have to make sure your electrical service and your breaker panel can handle it.  Also, depending on the hardness of your water, tankless heaters can be more susceptible to getting clogged up with lime so you may need to do regular maintenance to keep that from happening.

Curtis73 (Forum Supporter)
Curtis73 (Forum Supporter) MegaDork
4/27/20 12:00 p.m.
joey48442 said:

Does my title bother you?  It should


i was asking for opinions on replacing my old water heater, or going with a tankless on demand system?  Two of live here, but we tank longer than we should showers. Any experience with savings or not?



Make sure your gas line is up to the flow demands.  A tank heater might use 30-40k btus because it has the luxury of slowly heating and maintaining temperatures.  A tankless might use 150-200k btus.

I also have read that there is a time factor involved.  Once you turn on the hot water flow, THEN the heater kicks on and starts heating.  It may take a longer time to get hot water at the faucet than with a tank.

and YES.  The title bothers me wink

Driven5 UltraDork
4/27/20 5:45 p.m.

If you're electric, hybrid heat pump water heaters may be worth a look as well. It is my understanding that they're actually more efficient than electric tankless. Which is also the reason there were multiple (government and utility co) energy rebates/incentives that brought the hybrid heat pump price down to almost the same as a conventional water heater, but none to help offset the additional cost of tankless. Add to that we would have also needed to spend even more to expand our panel capacity to handle the extra breakers for a tankless, and it was an easy choice for us.

tr8todd SuperDork
4/28/20 6:54 a.m.

Can't get conventional water heaters any bigger than 50-55 gallons now because of new minimum efficiency laws.  You could do an 80 gal hybrid.  Unit costs around $2K and comes with 10-12 year warranty on tank, but only 5 of compressor/heat pump stuff.  Will save you money over conventional electric and is on par for operating costs with a conventional gas water heater.  The farther south and the warmer the climate, the more you save.  If you were talking about gas, I would do everything I could to talk you out of it.  The savings vs repair cost, install cost, etc just don't justify a retro install.  Maybe makes sense on a brand new structure or a place where they use a ton of hot water.  A place like a health club where somebody is always in the shower makes sense, but not in a home with two people.

mr2s2000elise SuperDork
8/19/20 12:43 p.m.

Have tankless water heater on 2 properties, love it. 



However, this morning, one rental property (house built 2001, water heater is gas and 12 years old, died). Called home warranty company. Quote is $1975 to replace. 

He says home warranty will pay $1500, and I have to pay $497.


Been on hold with warranty company for 2 hours. Figuring out,

1) why I have to pay?


2) If they will cut me check and I can have another cheaper contractor do it?






Just talked to warranty company. They say I have a ULINE 50 gallon. Their replacement is an American pro 50 Gallon. Nothing fancy. $1495 for water heater installed - they will cover. 


They are saying, I need the following done:

Expansion tank $395

Sediment Trap $125

Extend Pan Drain $35

T&P Drain $115

Cold Supply $75

Vent Short $65

Total: $810 addtional to water heater MINUS  $250 code coverage = My out of pocket $560







Our Preferred Partners