Another hot tankless water heater question

I have a Navien, it came with the home I bought. From what I've been told its the top of the line brand. I get between 92-96% efficiency (spec is 96%) - meaning every dollar spent on heating water via gas, 96% of that gas burned is turned into heated water. regulars tanks won't get you that , they sit somewhere between 45-65% efficiency. So you'll be saving right there off the bat in terms of turning your gas usage into heated water. With a tankless you will have to service it once every 12-18 months - the service procedure is called descaling - you can DIY but if you pay someone atleast in Toronto its about 130 bucks. there are youtube videos - basically you run vinegar through the system for about 30 min-45 min. The other benefit of a tankless is it takes up little space in your basement as its wall mounted. Installation cost of a tankless I have found is often more than regular tanks. The only thing I find annoying about tankless is that sometimes I have to wait at most 10 seconds at the tap before hot water comes out, but this is a function of the size of your home as I have a lot of distance between the tank and where my bathroom sinks are on the top floor...this isn't an issue on the main floor.

How big is the tankless unit you are being quoted (how many btu)? Does the tankless include the relocation?

I'm not sure about the BTU. But he said 7gpm. Yes it includes the relocation.

ashishpatel wrote: ↑ I get between 92-96% efficiency (spec is 96%) - meaning every dollar spent on heating water via gas, 96% of that gas burned is turned into heated water. regulars tanks won't get you that , they sit somewhere between 45-65% efficiency.

Newer tanks are 96% efficient.

http://www.gsw-wh.com/en/products/envirosense-pdv

Gee wrote: ↑ Newer tanks are 96% efficient.

http://www.gsw-wh.com/en/products/envirosense-pdv

The tank you linked is a condensing unit. Condensing units cost the same as a tankless sometimes more.

New power vent regular tanks are about 67-71% across manufacturers. New atmospheric vent units are about 59-61%.

Naiven - top of the line? Lol they are not...they are on the lower end of a value brand.

bubuski wrote: ↑ The tank you linked is a condensing unit. Condensing units cost the same as a tankless sometimes more.

Any advantage to these tanks over tankless?

You won't make up the cost difference for tankless, esp. considering tankless needs flushing every couple of years.

However, more important for the decision IMO are your needs and usage habits. Is a 50 gallon tank good enough for you? A tank will usually provide the fastest hot water flow, but it's a limited amount. Tankless will often provide lower flow, but may be enough for two 2.5 gpm showers simultaneously, and it is unlimited.

In my case, my 50 gallon tank was problematic in the winter (with very cold incoming supply from Lake Ontario) when we wanted to fill our oversized bathtub. Especially if I used any hot water beforehand, I'd get only a partially filled lukewarm bath. OTOH, with my tankless, it's never a problem since the hot water is unlimited, but it takes longer to fill the tub.

My original plan was to go with a 75 gallon tank, but the space wasn't big enough for it. Since a larger tank wasn't an option, we then decided to go with our Rinnai 199000 BTU tankless model, although we have a very small electric tank after the tankless, in order to eliminate the cold water sandwich effect.

Yeah I think right now, for 2 adults, 50 gallon tank is plenty. I don't think we'll be running out of hot water very frequently. We'll wait about when the kid reaches about 10 when he starts to develop his own usage pattern until we switch.

I don't think the savings in operating costs is enough to out weigh the initial investment and maintenance costs.

Thanks

Gee wrote: ↑ Any advantage to these tanks over tankless?

They are not worth it. Too complex and not DIY-friendly even when compared to a tankless. An advantage could be better flow rate and a bit of hot water supply during a power outage.

bubuski wrote: ↑ They are not worth it. Too complex and not DIY-friendly even when compared to a tankless. An advantage could be better flow rate and a bit of hot water supply during a power outage.

The recovery rate of these units are suppose to be pretty quick. I am stuck with one of these units, which I had to buy out from the rental company the builder stiffed me with. You're right, they cost as much as a tankless unit.

7 years ago when I swapped out a rental tank for a tankless my gasbill dropped about $20-30 a month. We were very high usage however as my wife did home daycare in the house. Descaling is very easy and just a matter of a couple hoses and a small water pump to circ descaling sultion through the unit..

My unit did fail after about 5 years. It was the power vent fan. The error code on the unit was very specific. I overnighted the part and it took me 20 minutes to swap. They are not really that hard to work on despite how complex they look inside.

I have since moved. I miss my tankless but we own the current tank so my motivation to swap is drastically reduced.

restie wrote: ↑ So I have a decision to make.
Getting a 50gallon tank water heater will cost me $1500 including install (we're moving the location of the water heater so doing some water and gas pipe work. Not just a simple replacement)
A tankless heater will run me $2000. Installed
Is the $500 difference worth it?

Right now, there are 2 adults in the house and a baby on the way.
Life expectancy of a tankless water heater is about 20years according to the internet.
I'm expecting the water usage to change when the kid gets older. So mid cycle of the lifespan of the tankless.

run dishwasher, laundry and two adults take showers at the same time for as long as they want and still have hot water on demand without blinking is worth it.

So is saving space. I love my R98 and I would never consider going back to a tank heater.