BiggerPockets

from what i have heard, at least in SFR, tankless water heaters are great. One down side is cost. Guess you would have to weigh the cost of installing one in rental property, but in theory they should work just fine

is that true? if I'm using an electric tankless i will need multiple units.

i thought they made units that run for the entire house?

i have a 2/2 that I want to install a tankless for, do you think i would need multiple units?

I talked to a guy the other day, that claims that he can get the new style units that are electric for $400 bucks per unit out of Chicago. I asked him about having to install several per SFH and he said that the one he installed in his house has no problem providing enough hot water for his entire family. He said the old unit did have problems, but the newer ones work great.

He wasn't trying to sell me one, so I don't think he was being dishonest.

After some initial enthusiasm, I don't think tankless is a good idea in apartments. Tenants in US are not used to tankless, and probably won't like the low flow rate. Also they have no idea how to take care of them.

I saw some models for $1200, and that is before installation.

We have installed many gas instant water heaters in commercial applications, very little maintenance. As far as apartments they are pricey $700 to $1400, but if installed properly they will last much longer than regular water heaters.

Ray Erspamer

Originally posted by Nate Nook

I like the idea of using one for a larger unit though, like the woman with the 16 unit property. That is prob a great idea. It would also resolve the issue of the low flow rate, since someone is probably always using hot water somewhere.

The largest factor is whether the apartment units are individually metered. On a 16 unit apartment that is on one meter it makes sense to use a tankless system.

I wanted to put a tankless in my 4unit once and the city inspectors said no. Said had to provide enough hot water for all units to take a shower at ONCE. This building was individual metered for all gas and elec but landlord always provided hot water from one heater and the water. No room for 4 heaters. City even said my gas heater had to go and replaced with 2 - 50 gallon electrics in series.

Problem with electric tankless is the required wiring for 'on' times. It takes alot and CAN dim the lights etc when it kicks on. MOST older buildings dont have enough wiring capacity to have one,,,without pretty expensive upgrades.

I had a gas tankless in a barn situation when I needed consistant unlimited amounts of hot water and 'loved' it.

In ones own home,yes worth it,,,in a rental TOO expensive

I've been talking to the guys at my plumbing supply house about installing these in 20-40 unit buildings. They explained that they are not a good idea for three reasons. 1. You have to learn how to use one as it is not the same as the hot water we use now (I guess it is either on or off and there are some other issues) 2. They are more expensive 3. They need a gas line twice the size a conventional unit serving the same number of units.

They all say that I could run my building on a small quick recovery unit or a string of small units (40s) and see a price savings. What I really want it to be able to replace and service the units within our company. If we have 40s it only takes one guy an hour to replace any one that goes down.

I have tankless in my house, and have no flow rate issues. Gas unit...I don't have experience with any electric models.

Also, besides saving you up to 25% on energy costs, ENERGY STAR gas tankless water heaters are one of the qualifying energy-efficiency improvements that are eligible for a tax credit (in the U.S.) IF you make the change January 1, 2009 through December 31, 2010. If you're a U.S. resident, you should read over the tax credit info for 2009-2010 before you choose products.
There (thetanklessheaters.com) is also a calculator that allows you to calculate various parameters of the water heater.