Getting new boiler,get separate water heater or not???

[crazy charlie]

New boiler is in my near future.I have conflicting recos from 2 boiler guys.One says to just get a boiler with a coil inside for my hotwater.Other guys says to get a slightly better quality boiler with Riello burner for same money w/o coil and get a separate water heater.Boiler is oil fired and water heater would be electric.Claim for separate water heater is that the boiler will not be running as often saving oil costs and we all know where oil prices are headed.we are a family of 2 and dont have huge hot water consumption.What do you guys think??I am ready to flip a coin.Charlie

 

[dwco5051]

New boiler is in my near future.I have conflicting recos from 2 boiler guys.One says to just get a boiler with a coil inside for my hotwater.Other guys says to get a slightly better quality boiler with Riello burner for same money w/o coil and get a separate water heater.Boiler is oil fired and water heater would be electric.Claim for separate water heater is that the boiler will not be running as often saving oil costs and we all know where oil prices are headed.we are a family of 2 and dont have huge hot water consumption.What do you guys think??I am ready to flip a coin.Charlie

Using rounded off numbers to slide rule accuracy it cost about twice as much to heat water with electricity at 15 cents a KWH than with oil at 3.00 dollars a gallon assuming 85% boiler efficiency. Sounds like a simple choice but you have to figure in if you live in a moderate climate and only heating the house 8 months a year things change. The most in inefficient time a boiler runs is during start up when the refractors and boiler casing is cold. Add standby losses up the flue during down time and radiant loss to surrounding spaces when off and that 85% goes way down hill. If that heat is going into a space that may be air-conditioned in the middle of Summer even more. There is maintenance on coils if you don’t have soft water which may require acid cleaning. Also the coils require a tempering valve and they are not trouble free.

Since your hot water demands are medium to low my gut feeling would be forget the coils.