Water heater: Tank or Tankless

[KDpoolguy]

Looks like our 19 year old tank water heater is on its way out. Wanna plan on a replacement and really am torn on type. Our water closet opens to the outdoors, so I’m less worried if the Tank fails, so a tank direct-replacement may be OK for us. I’m reading more that the tankless may not be worth the extra cost? Hey! My Active20 robot controller actually shares the water heater closet.
We have a larger home with a unusual courtyard layout and the master shower and tub are (no joke) over 90 feet a way from the tank-a large distance to travel, so it’s got the recirculation pump running almost 24:7 to get hot h2o hat distance.
any recommendactions?

 

[cfherrman]

Point of use water heater for the master, I have no experience with these but I want 2 of them as one use is 40' ish away.

I would think a tankless with a recirc running a lot is a bad option.

 

[Rancho Cost-a-Lotta]

You won't be able to use a conventional re-circulation pump with a tankless system since the unit requires a minimum amount of flow to generate heat. I miss the re-circ pump. Our current home had a tankless system when we moved in. If more than three sources of hot water are turned on at the same time, pressure decreases significantly. The $75-$100 filter requires replacement every 18-months or so. If I had the choice, I would have stuck with the conventional water heater. Not worth the up front costs and I don't even want to think about repair/replacement costs.

Just my 2 cents...

 

[JJ_Tex]

We had tankless in our old house and liked it, but in our current house we have tanked with a recirculating pump and like that even more.

When we replaced ours tanked water heaters a few months ago we stuck with the 2 50 gallon tanks because that was cheaper than switching to tankless, the tanked maintenance is less, and I didnt love the thought of the tankless running a bunch on a recirculating pump.
If we werent already plumbed for recirculating, I might have been tempted to go tankless again.

 

[Fuldo]

I believe the only advantages of on-demand is reduced energy use and reduced footprint/volume, every other aspect of those devices is negative. The energy difference probably isn't much with one of the more modern well insulated tank type heaters and they can be further insulated by the owner after installation. Lost heat from a tank heater is often not lost as such, it can sometimes keep a basement space fairly warm in the winter, especially in colder climates.

 

[HeyEng]

I think much of this would depend on energy costs. The on demand heaters use a LOT of NG and if it's expensive then that could be a deciding factor for me. As far as the recirculator, we too have one for our house (same issue w/ distance) and love it. However, to keep energy costs down...we don't run it 24/7, just from 8 am to 10 pm since it's pretty rare we would need immediate hot water during the night.

 

[santacruzpool]

Being in Palm Desert you have lots of sun, so do you already have PV solar? If you do, and especially if you generate any excess electricity, you might look at one of the heat pump electric water heaters as an alternative to a natural gas one.

I had a regular old NG tank style water heater in my first house - when it failed and damaged our kitchen we replaced it with a Takagi tankless heater. The tankless lowered our NG costs a little, but there were some quirks with it including a "cold sandwich" due to the tankless purging the tank after it shut off that sent a slug of cold water back into the hot water line. Plus, if you turned the hot water down too low (think warm water for hand washing) sometimes it wasn't enough to keep the flow switch running and everything would go ICE COLD...that also happened in the shower a few times in the summer when I wanted a less than hot shower.

Right now in our latest house we have one of the super high efficiency NG water heaters (ours is a Polaris). This does the water heating for our domestic hot water and provides heat for our radiant floor heat in our downstairs slab along with our upstairs wall radiators. We never run out of hot water with one 50 gallon tank since it can heat water so quickly and effectively. I can fill a big tub, run laundry, have the kids take a shower, and have the heat on and it still keeps up. We have never run out of hot water.

The more efficient gas heaters are much more expensive than a standard old school tank model and may not pencil out over the life of the unit, but for us it is what works for our home since we use it for heating and domestic water.

Back to the electric type - if you have solar generation, or are planning it in the future, the heat pump heaters are pretty nice - I think that is the direction I would go in hindsight. We didn't do solar when we built our home so NG was a much cheaper way to go.

 

[Newdude]

Couple of thoughts. We also had the wait forever for the bathroom water to get hot water at the further bathroom (not 90 ft but still). When I had the area between the heater and bathroom open I installed a bigger line to solve the problem. The extra volume wooshes the cold/room temp water out in a second or 3. If you ever have the chance during a renovation, you won’t Regret it.

Also I want to offer a different option. When my furnace died I told the plumber that I would soon have 2 teenage girls and a Mrs and wanted never ending hot water. He put in a TurboMax indirect tank heater. It works with any heating system. The new furnace got an extra zone that goes to the heater. The furnace keeps the (50 gal ?) tank full of hot water and the house line runs through the tank through a worm/coil like thing. It’s on demand and more efficient than the typical direct heaters. My electric tank heater cost a fortune and ran out with 1 long shower.

 

[wireform]

Couple of thoughts. We also had the wait forever for the bathroom water to get hot water at the further bathroom (not 90 ft but still). When I had the area between the heater and bathroom open I installed a bigger line to solve the problem. The extra volume wooshes the cold/room temp water out in a second or 3. If you ever have the chance during a renovation, you won’t Regret it.

Also I want to offer a different option. When my furnace died I told the plumber that I would soon have 2 teenage girls and a Mrs and wanted never ending hot water. He put in a TurboMax indirect tank heater. It works with any heating system. The new furnace got an extra zone that goes to the heater. The furnace keeps the (50 gal ?) tank full of hot water and the house line runs through the tank through a worm/coil like thing. It’s on demand and more efficient than the typical direct heaters. My electric tank heater cost a fortune and ran out with 1 long shower.

Indirect is a good way to go. If you want to make the hot water last even longer you can put a tempering /mixing valve right out of the tank so you won't take more hot water then you actually need and then cool it down with the cold water thereby leaving the max hot water in the tank.

 

[KDpoolguy]

Thanks for the info! I believe I really have to stick to the tank water heater. Thankfully my home has a dedicated recirculation line so I have on demand heat—as long as the recirc pump is on. I’m thinking maybe I’ll take the money I save from tankless to a new digital recirc pump (I think my pump is a Grundfos), so I can choose different pump times for weekdays and weekends. Maybe they have a WiFi recirc pump.
I think Costco sells Water heaters?

 

[Rancho Cost-a-Lotta]

Thanks for the info! I believe I really have to stick to the tank water heater. Thankfully my home has a dedicated recirculation line so I have on demand heat—as long as the recirc pump is on. I’m thinking maybe I’ll take the money I save from tankless to a new digital recirc pump (I think my pump is a Grundfos), so I can choose different pump times for weekdays and weekends. Maybe they have a WiFi recirc pump.
I think Costco sells Water heaters?

Good decision. How about using your existing pump and plugging into a WiFi smart plug? 24 hour control from you phone for under $20...

 

[HeyEng]

Good decision. How about using your existing pump and plugging into a WiFi smart plug? 24 hour control from you phone for under $20...

We have an old school digital timer for this, but just because the WiFi plugs normally only have the two prongs. I am sure there are others that have 3 prongs, but I have been too lazy to hunt one down.

 

[Rancho Cost-a-Lotta]

The plug I linked is a 3-prong, and good for up to 15 amps.

 

[KDpoolguy]

I researched the Official Grundfos digital timer (THIS ONE) FOR $45. I have many Wifi plugs now and love the flexibility. I wonder if there’s a danger in using one for the pump? How are they different? The Official one is awful and SO confusing to program. I love the idea of setting a WiFi schedule, but also to just tell Alexa to turn it on minutes before I take a shower. It may be convoluted to have to schedule so many on/off periods, but maybe I’ll give it a shot.

 

[Rancho Cost-a-Lotta]

I've used WiFi switches and plugs from three different manufacturers. I like Kasa TP-Link the best. It's the easier app to schedule and the interface is the most user friendly. If you already have WiFi plugs, try to find one from the same manufacturer for consistency. Check Amazon on Black Friday for deep discounts. Assuming the amp rating of the switch is not exceeded and you have good a good WiFi signal at the plug location, there should be no issues with safety or connectivity. Worst case scenario is you don't like it and you end up with a $20 automation device for your Christmas tree lights.

 

[jseyfert3]

Also I want to offer a different option. When my furnace died I told the plumber that I would soon have 2 teenage girls and a Mrs and wanted never ending hot water. He put in a TurboMax indirect tank heater. It works with any heating system. The new furnace got an extra zone that goes to the heater. The furnace keeps the (50 gal ?) tank full of hot water and the house line runs through the tank through a worm/coil like thing. It’s on demand and more efficient than the typical direct heaters. My electric tank heater cost a fortune and ran out with 1 long shower.

Does it though? I looked this up and it appears it's a glorified heat exchanger. This means that it requires a boiler. While the boiler can be powered by any means that can produce hot water (electric/oil/gas/etc), you need the boiler in the first place. This means it won't work if you have a gas or electric forced air furnace, for example, which would be the majority of people in North America.

 

[Newdude]

Does it though? I looked this up and it appears it's a glorified heat exchanger. This means that it requires a boiler. While the boiler can be powered by any means that can produce hot water (electric/oil/gas/etc), you need the boiler in the first place. This means it won't work if you have a gas or electric forced air furnace, for example, which would be the majority of people in North America.

When I looked up the details for this post I stopped thinking at the ‘works with any system’ part. Now that you point it out, you would certainly need ‘a system’ that has a boiler in the first place, but a lot of homes do. If you were using a stand alone electric hot water heater as your hot water source, it would not be for you.

 

[jseyfert3]

That's true, a lot of home do have boilers, but I think force air furnaces are more common. And by "any means that can produce hot water" I mean a dedicated boiler, not a domestic hot water heater. You would certainly not want to use that if you had an electric hot water heater as your hot water source, but you can get an electric boiler, and if you had that already, it actually would probably make sense to get this.

Of course electric boilers aren't common at all, because electric restive heat is usually the most expensive way to heat your house. My girlfriend (now wife) had an apartment heated by an electric force air furnace. It cost her more to heat her 600 square foot apartment in the winter than I paid for both gas and electric at my 1400 square foot house with an 85% efficient natural gas furnace. And she kept it a lot colder than I kept my house to boot!

 

[Newdude]

If it’s applicable to anybody, I recommend looking into it. I’ve had mine for about 10 years now and it has performed exactly as promised. It can rival an on demand heater and I will gladly replace it when the times comes.