So, really, how much more efficient is an indirect hot water heater vs a tankless coil? I understand that with an indirect you could have the boiler fully shutdown between "calls" for heat, but if it has to keep the indirect hot water tank hot, wouldn't it have to kick on just as often as keeping itself hot? The other thing is that some people say you can't use an outdoor reset for a tankless system, but there is a Honeywell that allows for keeping the "Low" limit, then the outdoor reset just changes the "High" for when the system has a "call" from one of the zones.
So, whats the difference between say a Weil McLain w/tankless set up with a Honeywell outdoor reset, Low set to 130F to maintain dhw vs the same boiler with a tankless and the tankless is set to maintain 130F (don't want lower than that due to Legionares Disease risk, obviously use a mixing valve)?
So, whats the difference between say a Weil McLain w/tankless set up with a Honeywell outdoor reset, Low set to 130F to maintain dhw vs the same boiler with a tankless and the tankless is set to maintain 130F (don't want lower than that due to Legionares Disease risk, obviously use a mixing valve)?