Newbe supplemental tankless questions...
We’re planning an extension to our master bath, and would appreciate input on adding an electric tankless WH as supplement to our existing plumbing within that expansion. Current configuration has a single MB sink at the outside (framed) wall that we intend to remove for the extension. Existing plumbing comes up out of the slab into that wall, so we understand some of that slab will have to be demoed/replaced to connect to that location for the hot/cold water source to the expansion. Planned addition includes a double shower, two sinks and possibly a tub. Our intent is to have the tankless heat the hot water line (cold water slug?) between the natural gas tanked WH, (about 40 ft away in the garage) and the master bath.
1. As we haven’t opened that wall as of yet (thus suspect ½” supply at that existing sink) , is it reasonable to reroute that existing hot water supply line (under the future slab extension) up thru the master bath electric tankless to the new shower heads and sinks?
2. Are we correct in assuming that since the tankless will only be a supplement at the remote location (master bath), that a smaller (less wattage) unit will work well?
3. Is there a need for a water filter at the input to an electric tankless WH?
4. As we eventually intend to convert the garage gas WH to tankless, are there any issues we need to be aware of?
Thank You, in advance for your expertise,
Trade-off assistance please
Thanks for the thorough "insulation cost" info Dana, I'm sure it will be very useful during our plumbing rough-in. Right now, I'm embarrassed as my brain/finger coordination, or lack there of, is exposed. You were correct, I did mean to ask about "installation costs" - Thank You! I could be wrong, again, but it seems to me that installing a nondedicated-return recirc set-up, as a retrofit, into our existing slabed home would be more beneficial to the Plumber than to us.
That said, I think we're back to incorporating an electric storage tank in our MB addition. Now the trade-off, I think, is between a small supplemental booster tank (probably 2.5 to 4 Gal) feed by a 1/2" line coming from the main WH, OR a bigger stand-alone tank (6 to 10 Gal) feed by the (colder) 3/4" line from street. It seems, to us, that the initial cost (purchase and installation) is nearly a wash between the two.
Inupt Info: 2 adults / Central Florida / 2 individual 1/2" shower controller valves / 2, 2.5 GPM shower heads.
Questions / Requested Advice:
1) Since the small booster tank would only really be utilized to heat the initial cold water slug, from the main WH at the start of a draw, and maintaining the desired storage temp between draws, wouldn't the expected operating cost be quite low?
2) Any estimate of the street feed stand-alone operating cost as compared to the above smaller booster unit arrangement?
3) Would the increased water pressure/volume, at the shower heads, from the stand-alone 3/4" street feed, really be worth the (I think) increased cost difference as compared to the small booster 1/2" main WH feed?
4) Considering the above, would we better off just continuing to tolerate the approx. 1 minute cold water delay when turning on the hot water in the master bath?