It’s water heater replacement time at the casa. I have 2, 50 gallon units now. One has been down for awhile and the other is north of 10 yrs old. I got up this morning, considering the cooler weather, planning to swap both out. They are in the attic. Then the wife and I started talking over coffee about the possibility to make the move to tankless. We’re on natural gas only. Cost for the units, whether I buy two replacement tanks or go tankless, is nearly the same. $1200-1400. Although I’m not privy to tankless installation costs. Meaning can I manage that or need to hire someone?

Any thoughts on this topic? Have you switched, any lessons learned, etc. I would appreciate some input from the THF brain trust.

Thanks, Billy

I have the same in my house. Gas and 2 50 gallon tanks.

In the summer, my gas bill is about $40. That includes all of the surcharges and fees. I would get no cost savings on the heating water part of my gas bill.

I actually talked to a plumber 5-6 years ago about moving to tankless.

He asked if we ever ran low on hot water, I said no.

He said stay away from them. The PMs and the up front costs will cost you a lot more than just replacing the 2 50 gallon tanks with my scenario.

We have a tankless and I think it is called a endless hot water heater, it is not instant hot water but it never stops putting out the hot water. We love it!!!
We also had it installed in the attic above the garage and turned the old hot water heater closet into an additional pantry.

I wish I could have done tankless 10 years sooner, great choice

Yep 👍 all cheers for tankless.

I converted to a tankless in 2019 due to running out of water almost every night with the wife's whirlpool tub. I got busy gathering parts and the city permit. With the high efficiency units, you either have to go with stainless steel or PVC flue pipe, since the exiting exhaust temp is so low that the flue gas leaves the unit below condensing temperatures. Any carbon steel flue piping will rust out quickly becase the flue gas contains weak sulfuric acid, so don't use galvanized pipe either. Gas piping must be hard piping all of the way to the tankless unit to minimize gas pressure drop. Don't undersize your gas piping. My unit required 3/4" gas piping. Because the unit generates condensate due to the low temperatures across the secondary heat exchanger, you have to have a drain for the collected condensate. So if you don't have a drain at you existing tank, you will need one at your tankless. You will need to have 110vac available for your tankless. I was able to install most of the new connections before making the cut over, so I was only without hot water for a few hours. My unit has been completely reliable and can supply hot water to the shower and tub at the same time. The biggest hassle with the unit is to run a descaler through it every year if you have hard water. I installed the needed valving to do this, so it is simple to do, but you have no hot water while you descale.

I've been satisfied with mine, but I don't know it would have been worth the cost, if I had paid a plumber and an electrician to do it.

Correct, nowadays you're looking at upfront install costs of $2-4K between plumber and electrician. If you have those skills by all means have at it. As said, you need to annually do a descale water flush and reset and don't forget the reset and "on" switch. Father n law forgot the "on" switch in Corpus Christi, TX on the side of house we were on and it made for very cold showers during our X Mas there. After my questioning it, he checked it later and realized it was "off" after the water descaling and reset. One other thing I can say is that it takes a little longer for the water to heat since the piping/coils must heat up but once heated, it does come out plenty warm.

I am not a fan of Tankless. You have to have them flushed yearly or you loose your warranty. If they break it can be a pain being on the phone with technical support for hours getting issue identified, plus then they will have to ship a part so you could be down for days.

I remember when we had the winter freeze 2021 I saw people who had to stay in hotel for 3 to 4 months, there were no tankless units available

Depends on how you house is plumbed you may have to upgrade gas lines, vent lines, electrical outlet, build a mount for the unit to sit on.

I have seen tankless reduce pressure to certain parts of the house.

I have (2) tankless 50 gas water heaters in my attic, I have no desire to go tankless. I also put a recirculation pump on my water heater going to my Kitchen faucet since it was taking 3 minutes to get warm water there, after I did that I have almost instant hot water in my whole house.

My Takagi unit allowed me to set the discharge temperature and the minimum flow rate when it would turn on. But even with optimum settings, like DQ says it still takes longer to get hot water to the faucet. I now just wash my hands in cold water, unless you really need to scrub them, saving water and wear and tear on the unit.

We have a tankless water heater and love it

Go tankless. You’ll run out of water pressure before you ever run out of hot water.

Just me in the house now so I never run out of hot water. My water heater was in the attic. Several years ago it developed a leak and mice had clogged up the pan pipe with insulation. Fortunately there was a ceiling register within 2' and the water dripped out of it. Replacement water heater was relocated to the garage. I replaced 1 in the attic and decided I was not going to do that again.

Another happy, tank less water heater user!

Had one installed (Naveian) going on 5 years when we built this house. 3 bath house. Never have looked back . Wouldn't go back to conventional tank models. Haven't had an issue.

Residential, 4 or less people in the house…..ng or propane….solid investment.
Be sure to
Request a condensing unit as it is more efficient
PVC vented but will need a condensate drain or pump.

We bought our house in 2010 and the 50gal tank in the attic looked like it was ready to blow. Replaced it with a tankless as I didn't want that possible disaster in my attic.

It has been very reliable.

I appreciate all of the responses. Sounds like tankless is the way to go assuming you are ready for the adds like ac power, annual maintenance, and a few others. I watched a few YT vids and learn some stuff there as well. Not sure I will convert now but will certainly do it when we move. Plus a generator! On retirement countdown in 4 years or so. Planning on that being the last move and will most likely build on some property a long way away from the MetroMess. Barndo with a shop is looking real good.

[/quote]I have seen tankless reduce pressure to certain parts of the house.

I have (2) tankless 50 gas water heaters in my attic, I have no desire to go tankless. I also put a recirculation pump on my water heater going to my Kitchen faucet since it was taking 3 minutes to get warm water there, after I did that I have almost instant hot water in my whole house.[/quote]

Yes, a couple of the vids I watched added the recirc pump to cure that issue with tankless. Then my neighbor came by today and he added one like you, with his 2-50s and is now getting hot water to his master much faster.

Go tankless young man. Maintance is once a year unless your water ls soft water, you can go longer. To service you take 3 gallons of vinegar and run a continuous loop through the tankless unit only for 45 minutes. This is to flush the scale out of the system. Can buy hose kit on-line.

This is our first house with tankless and we love it. It's just the wife and me so no high usage. Even with company and lots of showers we have no issues.

I've got two of them. The cleaning/recirculating process take a whole 45 minutes. I do mine twice a year and never had an issue.

On some homes I built for customers with tankless water heaters we split the power wire inside the unit and installed male and female extension cord ends so an extension cord could be used for power from a generator. On one home the water heater was on an exterior wall beside a carport. The owner kept a power inverter ready to put on one of his vehicles for that purpose. I think the power needed for the spark device was well under one amp.

Your a home builder, I am seeing some smaller house like 3500 sq ft house, with around 3.5 baths (I assume) having (2) tankless units side by side.

In my area on a tank once you hit 4 full baths you need two 50 gallons and they are serial (Side by side in attic 2nd floor).

I am seeing new built homes with 4 bath and they only have one tankless but the gas supply is 1", these home are around 4500 sq ft, they are under construction and I count 4 full baths, and large garden tubs

I quit building three or so years ago. I only did one home with a tank water heater in the attic. I fought that idea, but that's what they wanted. I don't want any more water sources in the attic than absolutely necessary. We put tankless water heaters in boxes on exterior walls when possible.

Personally, I wouldn't have a tankless water heater unless it was one of two water heaters. If my tank heater goes out I can personally replace it from the plumbing supply or Lowes in a few hours. If a single tankless water heater goes out we would be in a motel or showering at the in-law's. Plumbers are in short supply and busy.

Trex put a 67 gallon tank in our garage 8 years or so ago and it has been awesome. Replaced a 50 gal, 16 yo rusted tank. Our family of four always have ample warm to hot water, no issues.

I agree with you 100% about tankless, if you have an issue it will be days until you can get it fixed, I hear plumbers are online with technical support for hours just to figure out the issue and then shipping the part and installation.

Years ago I went and took classes for 2 different tankless water heaters so you could be a "Certified Installer" after I was done I said I am not gonna install these, they are too much to go wrong.

I am 100% Tank Water Heater person as well.