Propane Hot Water Tank heater or Tankless? Help me decide.

[Diamondpilot]

I have a standard 40 gallon propane unit in my house. First one lasted 12 years and leaked. AO Smith. New one is a high end Honeywell unit. No complaints.

In my shop I have a on demand electric unit. Even with 200 amp service it makes my lights dim. It's on its own 220 30 amp circuit. I have welders, power tools, ect but that water heater draws some juice.

Chris

 

[BeezFun]

IMHO, the cheapskate way forward for the OP's question is to replace the anode, ...

I agree, and there are electronic anodes that don't need to be changed, but are more expensive. I put one in my tank about 3 years ago and it solved my smelly water problem. If you have a water softener and smelly water, the electronic approach works better than just changing anode material.

 

[i579rbd]

Can we add solar to this discussion? What does everyone think about installing a few solar HW panels on the roof which will supply a holding tank. Water then goes from the holding tank to either A) a tankless HW heater that will bring the temp up to meet the requirement or B) to a propane HW tank which won't have to work as hard to maintain a usable water temp.

 

[wjmst]

Can we add solar to this discussion? What does everyone think about installing a few solar HW panels on the roof which will supply a holding tank. Water then goes from the holding tank to either A) a tankless HW heater that will bring the temp up to meet the requirement or B) to a propane HW tank which won't have to work as hard to maintain a usable water temp.

Any time I have looked at solar, it just doesn't payoff for me. The cost to install and maintain is greater than the benefit from it. I live in western PA and don't get enough sun where I live to make it worth while. It may and probably will work for others.

Same thing with wind power. It just won't work for me.

 

[dave1949]

Can we add solar to this discussion? What does everyone think about installing a few solar HW panels on the roof which will supply a holding tank. Water then goes from the holding tank to either A) a tankless HW heater that will bring the temp up to meet the requirement or B) to a propane HW tank which won't have to work as hard to maintain a usable water temp.

That can be done.

You could also use a batch-type solar water heater. A simple batch heater would be a 55 gal. steel drum painted black. The sun heats the water in it, you use the hot water directly or move it to insulated storage, then begin heating a new batch of water. There are more sophisticated versions of that of course, but the concept is the same.

You could also use solar electric to offset the usage of an electric water heater in a grid-tied system. That is far less maintenance than dealing with fluids, and can be more cost effective in the right situation.

 

[Raspy]

The discussion about solar hot water always must include where you live, how much hot water you want, wether your priority is saving in the long run vs. short term and if you are doing it just to save money, add convenience or for the environment. It can also include your ability to build it yourself.

The simplest of all systems is the batch system and the simplest way to make it is with an electric water heater stripped of it's jacket and painted black. This can be laid down on a frame in the attic, close to the roof and under a large skylight. It will last for decades. Other systems can produce a lot more, but are also a lot more expensive and potentially troublesome.

I would never switch to a propane tankless water heater from an electric. But I am a big solar advocate and really like solar hot water. If it can be made practical, a solar backup to an existing electric would be very nice. This is what I'm doing in my house. Mine is a bit bigger though, with 600 gallons of storage feeding a 50 gallon electric water heater as well as a radiant floor.

Propane is a problem in a number of ways and tankless water heaters should be looked at carefully and honestly before buying one. Of course, there are exceptions to this thinking. Are you on the grid and living full time in the house you want this for?

 

[PILOON]

Have I not read (maybe on TBN) that tankless is mainly cost effective in areas where the ground water is fairly warm?
Seem to recall that 40 deg heat rise is the optimum range.
Taking 40 deg ground water and heating to near boiling is very costly, especially with hydro rates in some areas.

IMHO, a good 220v glass lined foam insulated tank is probably still the most cost effective hot water source. (or gas where prices are affordable except gas tends to cost 2-3X electric tanks)
No matter what brand tank, life tends to be 10 years. In fact many condos mandate replacement every 10 years.

 

[schmism]

consider a traditional hot water heater tank with a booster heater on the master bath. A tankless boster will look at the incoming water temp and boost it to a preset temp. So you can keep the large 40gal at 110 or something and boost it to like 130 at the master bath for longer showers or filling the big whirlpool tub.

 

[the old grind]

IMO, tankless heaters are snake oil for primary home use, best for remote/remodel applications. Lotsa reasons I feel that way: experience, friends who didn't buy again, call-backs about temp variations not controlled by code-required/tested anti-scald valves and that issue made worse by low flow shower-heads. (Don't get me started ..)

btw: In a cost-cutting era of manufacturing, conventional water heater warranties are based on an average 'first thing to go'. That's much of why 10 or 12 yr is so common, and '20-year' parts aren't even put in there anymore. R&R of conventional heaters are a lot of my pard's service work anymore, tho' with luck some will have 'basic' units that outlast their warranties vs what we typically 'pull' at ~10yrs or so, avg. They're still the best o'all for most, even with their now-shorter service lives and 'disposable' character. btw: folks don't carry decades-old Zippos like they used to, either.

Solar preheat? Sounds like a 'hybrid' I could get behind. How about a low-maint passive system. Works better in some regions, seasons, yeah but always a positive if well engineered, no?. Would one absolutely have to justify a cost saving to the very dollar to want to try it? Not me if I got another urge to 'make something cool' that's useful or even .... green. ...

 

[Obed]

We stayed with some friends who had a tankless water heater. At their house, unless you ran the hot water at the sink full blast, the water heater would not turn on. The tankless units will not heat water if the gpm flowing through them is too low. So if you like to run water in the kitchen sink at less that full blast so you don't splash water everywhere, you won't get any hot water.

I don't know if there are settings you can change on the tankless heater to make things better. We were considering tankless for the house we were building, but the experience at our friends house changed our mind. We didn't want to chance it unless we could first see a system working to our liking. We ended up putting a gas tank water heater in our new house.

Obed