Any benefit to increasing pipe size before and after Boilers tankless coil?

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Any benefit to increasing pipe size before and after Boilers tankless coil?

Author: av8042 (NY)

Hello All,
I have a slant fin L40-PT oil fired boiler with a coil. the taps are 1/2". would there be any benefit in
using 1/2"-3/4" adapters right in and out of coil? I get i'm limited to the amount of hot water coming
from coil but, the fact the 3/4" pipe would hold more hot water would possibly help with overall volume after being tempered? Am I chasing my tail here? I am eventually going to add an electric HW tank in the near future for the summer months and have both work together. Thanks, Alex

Re: Any benefit to increasing pipe size before and after Boilers tankless coil?
Author: packy (MA) since you will have to control the flow of cold water into the coil with something like this... it makes no sense to run 3/4 cold. but you can use a 3/4 tempering valve with the hot and cold inlets reduced to 1/2 and the tempered outlet keep 3/4. you will see a minimal benefit but it will help.
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