Haselsmasher
New Member
I'm very close to signing a contract on a tankless install. (It could happen tomorrow - which is why I hope I can get input ASAP here.)
I live in northern CO. If I assume a winter cold water temp of 40 degrees F I need to have a 75-80 degree raise to get it to 120. The spec sheet for the unit I've decided on (Navien) says it'll produce 5.1 gpm at that temp rise.
We have three showers in the house - with flow rates of 2.25 gpm per shower. On one level I'd conclude that in this winter scenario the heater couldn't supply three showers simultaneously. However on another level I'm thinking that showers don't get used at full hot; that one can likely assume that 75% of the total flow needs to be hot. So if I take 2.25 gpm/shower *.75 hot/shower *3 showers = A little over 5 gpm of hot needed for 3 showers.
So - what do folks think? Is it reasonable to conclude that in winter this unit could support 3 showers simultaneously? (It's a 199,000 BTU unit.)
Thanks!
Jim
I live in northern CO. If I assume a winter cold water temp of 40 degrees F I need to have a 75-80 degree raise to get it to 120. The spec sheet for the unit I've decided on (Navien) says it'll produce 5.1 gpm at that temp rise.
We have three showers in the house - with flow rates of 2.25 gpm per shower. On one level I'd conclude that in this winter scenario the heater couldn't supply three showers simultaneously. However on another level I'm thinking that showers don't get used at full hot; that one can likely assume that 75% of the total flow needs to be hot. So if I take 2.25 gpm/shower *.75 hot/shower *3 showers = A little over 5 gpm of hot needed for 3 showers.
So - what do folks think? Is it reasonable to conclude that in winter this unit could support 3 showers simultaneously? (It's a 199,000 BTU unit.)
Thanks!
Jim
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