Guys, Adrian's furnace thread just reminded me there's a whole panel of people right here willing to share their knowledge on all sorts of topics, so here goes:
My water heater is getting old and my local service dude mentioned the tankless idea as an eventual replacement. I have absolutely zero experience with the tankless heaters. I get them in concept but I don't know where to start to figure out if it would be worth the switch for my family of 5. I am on natural gas as my fuel source. Thoughts? Things to consider?
Dan, i have had a Bradford White
tankless water heater for a couple years now and have no regrets whatsoever. However, I'm a single homeowner and don't use much water.
Some things to consider are the size of your house, having a family of five, and water consumption. Because instantaneous water heaters only function when there is a call for water (specifically hot water), they have a limit on the amount of hot water they can supply at one time. For example-if someone is having a hot shower, and you are doing a load of laundry with hot water, you may not get any hot water if someone wanted to do the dishes at the same time. I haven't done any research in a long time, but I'm pretty sure the water heaters are rated on the projected demand per household, and the size of the house.
Something else to consider is that they are extremely efficient in the sense that they don't rely on a constant energy source to keep them running, like a contemporary water heater, but, they are extremely inefficient to run, and that's where questions arise i.e. if there's a large family that will rely on a lot of hot water, they technically might not be that efficient. My water heater puts out more BTU's than my furnace.
Another thing is when you turn on the hot water tap, you won't get hot water right away, and you may have to wait up to 30 seconds or possibly even more if it's a large house.
As Adrian said, Shawn is the expert, as it's his field of work, but hopefully I have provided you with some information that you previously didn't know.
If you have any other questions, ask away, and I'll help as best I can.