Tank vs. Tankless H2O heater

[Deere Dude]

The situation is;
I just bought a house with a 20 year old 50 gal tank LP Power Vent heater in a tight closet. It works fine now but am concerned about a leak then I have to scramble to replace. It will be a bear because the door frame is smaller than the tank.

I have a 3/8 coiled copper tube to the house and then 1/2" coiled copper tube run through the house for the gas supply.

Considering a tankless H2O heater from Menards to put in it's place.
I never installed one or used one but they have been around a while so I am considering one..

Any pros and cons from experience that I need to be aware of would be appreciated.

Thanks,
Chuck

 

[dmccarty]

Since you would be using gas, a tankless system will work. I looked at a tankless systems years ago for electric and I did not think it would heat our well water up enough. At the time, about 2004, our plumber was installing tankless gas systems. We talked to him a few years ago and he stopped installing tankless systems due to problems with hard water. We have pretty hard water, so hard that we have to use CLR on shower heads and such every so often.

If your water is treated or naturally soft, then this might not be a concern.

Back in 2004, a tankless heater was much more expensive than a good quality tank system so we bought a 80 gallon tank that uses very little power. Another big plus with the tank is that if we loose power, we have a ready supply of 80 gallons of water.

Later,
Dan

 

[Gem99ultra]

Before we moved in we had a plumber pull an almost new 50 gallon water heater out and toss it. The tankless heater installed was $1600. Getting a $1500 tax credit was certainly nice too. Also, using only 75 gallons of propane total for all of last year was a nice savings. Personally, I rate tankless water heaters head and shoulders above both electric water heaters and gas heaters.

I can't say enough good things about our tankless water heater. Instant hot water and not heating up 50+ gallons of water full time just to get it. The tankless heater only needs a 110v power supply to ignite the burner, and that's off until you turn on the hot water flow, then it's off again. Ours is a full house unit so there's no running out of hot water - ever.

My only regret is that I didn't also put a small one under the kitchen sink. Small expense actually, but lots of convenience for the lady of the house.

The Renai system that we bought does have a drain line to flush the system - annually recommended. Since we're on a water well and occasionally have sand, we do flush it as recommended.

 

[mddorange]

When we lived in Japan, everyone had tankless water heaters. They used two, one very small one for the kitchen and one a little bigger for the bathroom. They all ran off propane.

 

[bigtiller]

The situation is;
I just bought a house with a 20 year old 50 gal tank LP Power Vent heater in a tight closet. It works fine now but am concerned about a leak then I have to scramble to replace. It will be a bear because the door frame is smaller than the tank.

I have a 3/8 coiled copper tube to the house and then 1/2" coiled copper tube run through the house for the gas supply.

Considering a tankless H2O heater from Menards to put in it's place.
I never installed one or used one but they have been around a while so I am considering one..

Any pros and cons from experience that I need to be aware of would be appreciated.

Thanks,
Chuck

A lot depends on how long the 1/2" line is and the BTU requirement. But in order to get enough BTU's, I suspect you will need to replace some of it with 3/4" black iron. This would be a trunk line beginning at the regulator that everything else would draw from.

 

[Deere Dude]

A lot depends on how long the 1/2" line is and the BTU requirement. But in order to get enough BTU's, I suspect you will need to replace some of it with 3/4" black iron. This would be a trunk line beginning at the regulator that everything else would draw from.

Good point. The tank to the regulator with 3/8 is 40' and then maybe 50 some feet across the house with 1/2". I'll have to do some calculating as soon as I find the heater requirements.

 

[kenmac]

I'm an old school plumber... I like the tank...I've seen too many tank less have the water coils stop up with deposits..You also have many parts and maintenance to a tank less that you don't with tank type..There is still a market for tank type water heaters ,and always will be....They are simple ,and the parts can be had from most anywhere.. You don't have to call a surgeon to work on the tank type

 

[Rustyiron]

I have heard that a modern (well insulated) tank type HWH has very little standby loss when no water is being drawn, and it takes minimal energy to "bump" it back up to temp's. The "on demand" tankless use/require massive BTU's to raise the temps of well or municipal water to 120* and they are not the great energy savers that they were supposed to be, and considering the initial purchase price?. Now the new heat pump HWH's are interesting.

 

[kenmac]

Those massive BTU'S are 199,900...If you don't get in and out of the shower quick..You'll use a ton of gas at that rate

 

[PILOON]

I have heard that a modern (well insulated) tank type HWH has very little standby loss when no water is being drawn, and it takes minimal energy to "bump" it back up to temp's. The "on demand" tankless use/require massive BTU's to raise the temps of well or municipal water to 120* and they are not the great energy savers that they were supposed to be, and considering the initial purchase price?. Now the new heat pump HWH's are interesting.

We had a 5 day power failure and on day 5 I simply could not hold off a shower no matter how cold the water would be.
SURPRISE! Without adding any cold to the mix I enjoyed a normal shower. Modern day tanks are so well insulated that water stays warm that long.