Atticweb
New Member
Hope I have the right place, I'm new here.
Just had installed the electric tankless model in title of this post, and upgraded my electrical supply to 200 amp to handle it. Costly but various reasons for doing so (venting issues, etc.).
All work was well done. Everything works fairly well, minus wait times for hot water and occasional cold shots when someone else turns on a faucet.
Main issue follows with the pertinent facts; I've seen other similar issues here with showers, but I believe mine may be different.
Facts are this: one shower and one sink in one bathroom, upstairs, both off the same hot water supply line.
Sink is within couple degrees of set temp on unit (set to 108° for example, get at least 106°).
Shower, the supply for which breaks off same pipe as sink, is 20° colder! Luke warm at best.
The SE unit adjusts pressure to the temp requested; that is, to keep desired temp, it reduces gpm.
I have an old Moen shower faucet/mixer type, over 30 years. I'm pretty sure it must be mixing cold with the hot and basically not "talking to" my new tankless. I don't think the cartridge has anti-scald it's so old, but it might. Seems to me if you can set your heat at the unit, you don't need the anti-scald. Also the "posi-temp" feature seems like it might interfere with what the tankless is attempting to regulate.
I've found no help online or anywhere else so far.
I was all set to order a two-valve non-mixing Kohler unit to replace the mixer, as I'd like to be able to control just hot, etc., myself without the mixer deciding what's best for me and fighting with the heater.
To keep already high expenses down, a plumber just convinced me to just replace the cartridge and thinks that might do it.
Any thoughts or suggestions would be helpful, and also any discussion of these mixer features vs. tankless flow control and temp setting may be helpful for others.
Thanks for your time.
Will James
Just had installed the electric tankless model in title of this post, and upgraded my electrical supply to 200 amp to handle it. Costly but various reasons for doing so (venting issues, etc.).
All work was well done. Everything works fairly well, minus wait times for hot water and occasional cold shots when someone else turns on a faucet.
Main issue follows with the pertinent facts; I've seen other similar issues here with showers, but I believe mine may be different.
Facts are this: one shower and one sink in one bathroom, upstairs, both off the same hot water supply line.
Sink is within couple degrees of set temp on unit (set to 108° for example, get at least 106°).
Shower, the supply for which breaks off same pipe as sink, is 20° colder! Luke warm at best.
The SE unit adjusts pressure to the temp requested; that is, to keep desired temp, it reduces gpm.
I have an old Moen shower faucet/mixer type, over 30 years. I'm pretty sure it must be mixing cold with the hot and basically not "talking to" my new tankless. I don't think the cartridge has anti-scald it's so old, but it might. Seems to me if you can set your heat at the unit, you don't need the anti-scald. Also the "posi-temp" feature seems like it might interfere with what the tankless is attempting to regulate.
I've found no help online or anywhere else so far.
I was all set to order a two-valve non-mixing Kohler unit to replace the mixer, as I'd like to be able to control just hot, etc., myself without the mixer deciding what's best for me and fighting with the heater.
To keep already high expenses down, a plumber just convinced me to just replace the cartridge and thinks that might do it.
Any thoughts or suggestions would be helpful, and also any discussion of these mixer features vs. tankless flow control and temp setting may be helpful for others.
Thanks for your time.
Will James