Posted 1/12/2021 21:24 (#8746628) Subject: Whole house tankless water heaters
Talk me out of installing a tankless water heater.
I have a 50gal electric now, it doesn’t keep up with my family- could be full of scale. My water is very hard even with an industrial sized softener and filters so that is a challenge. I would probably want to step up to a 75gal size which is probably 700 some dollars but easy to install.
I’m looking at propane tank heaters. Burner in the bottom could be an issue for scale and sediment. I have gas lines plumbed to the spot but would need to run the vent which is a bit of a pain to route the B-vent properly with all the clearances required. Could maybe get by with the 50-60gal size because the recovery is much better than electric but it would cost around the $700. At current prices, the propane would run cheaper than electric so that saves me $100+ a year.
My leading contender at the moment is whole house condensing type high efficiency tankless heater rated at 9.5gal and 199,000btu. This puts out 6gpm at 55deg water rise and should support 3 showers all at once so I think this would be a good size to for sure supply two showers and potentially another outlet. The venting is pretty simple, two runs of PVC 2” to a wall outlet. There is a maintenance reminder to flush the scale buildup when required. Gas supply, 110v electric and water plumbing are simple as well. Cost is about 1100 plus another couple hundred in plumbing valves and extras but I can install myself. This should be the cheapest on a yearly basis by quite a bit.
I’m okay with the economics from my research on the tankless so far but would like to hear other opinions and anyone’s experience good or bad with them. Curious why they are not more commonplace given their efficiency.
I also understand the time to warm up may be a little slow but I’m already on a pex maniblock system with home runs to each water consumer so IMO it is already pretty slow to respond. I probably won’t use the recirculating feature of the tankless heater either due to all the separate supply runs.