Tank less water heaters.

[Mr. P]

Anyone have one or know anyone that does?

Good, bad etc?

 

[glockmail]

I don't, but I work with a lot of builders who swear by them. I have a 50 gallon indirect fed from a boiler that can't fill my garden tub hot, and am thinking of adding one of these as a booster for the tub alone.

BTW the best system I ever owned was a tiny direct oil fired. It was a Bock, had its own oil burner unit, only 20 or 25 gallon capacity, but would heat 100 gpm 100 degrees, which basically meant that you could not run it out. It cost me about $7/ month to run.

 

[MGB]

The theory is that a tankless makes hot water only when called for and so saves money heating and storing water that cools and is then reheated ad infinitum until needed. But these units are far more expensive than conventional heaters. So you have to compute the cost savings and amortize them over the additional cost.

Electric units can require up to 80 amps. Propane and natural gas and oil fired units require a flue that may or may not fit into your home's capabilities.

BUT, you can use two or more tankless units (one for the kitchen and laundry, one for the bathrooms/showers) and save a tremendous amount of space over a conventional unit. My daughter in Brooklyn did this with her co-op unit and reclaimed an entire former closet in the kitchen to much better advantage.

As in most things, you pays yer money and you takes yer choice.

 

[remie]

We have one in an area on the farm that requires lots of hot water in a short period of time. Even the biggest hot water tanks could not keep up. We installed on made by RENAI (I think) and have been delighted with the results. The only down side was the price. If you want more details let me know and I will get you the particulars.

 

[Mr. P]

Thanks folks. I know they are more expensive to buy but not to operate.

How about the life of the unit compared to the typical water heater?

 

[remie]

Thanks folks. I know they are more expensive to buy but not to operate.

How about the life of the unit compared to the typical water heater?

Ours has only been in for four years....so too soon to tell. We have had zero problems with it and it IS much cheaper to operate. We project making up the difference of purchase price in six years. By the way ours is propane.

 

[MGB]

The life of any water heater is a function of the water it heats. Acidic water will rot the internals. Hard water will choke the internals with scale. Many tankless units use stainless steel internals instead of copper but not all do.

In general, a tankless unit will probably last about as long as a standard heater does using the water you have at your property. Sometimes, a water treatment system to correct acidity or hardness will pay for itself in longer life of water heaters, furnaces, washing machines, dish washers and such. A professional water treatment company could help you determine the quality of your water and the likely payback schedule if treated.

A good rule of thumb is that an appliance like a water heater will probably last about twice as long as the warranty. The warranty is predicated on the worst case scenario - agressively acidic water or high hardness. Another rule of thumb is that a tankless unit will use roughly half of the energy that a standard water heater would use.

Hope this helps.