NG Supply for tankless HWH

Kjmass1

I was looking in to tankless hot water heaters and my current NG supply lines. I have a 250 CFH regulator with 1.5" pipe feeding a 196K BTU steam boiler and a 3/4" line going to my existing hot water heater and Pro range.

Do I need to size my NG supply for everything running at once? I would need:

196k Boiler
199k Tankless WH
100k Range (4x 18k burners, 25k oven)

That seems like a lot...would my current setup work?

Kevin

Robert O'Connor_12

https://www.youtube.com/watch?v=vffdymvjluk

Abracadabra

roflmao.... i need to save this

bmwpowere36m3

Simple answer, Yes.

Rich_49

We have seen systems with the requirement for a new meter and regulator also when switching from tanked unit (40K) to a tankless (199K) . Problem being that when the rated CFH is exceeded the pressure drop through the meter increases from .5" wc to 2 " wc . This could and has left numerous folks not being able to supply the necessary 6" wc minimum .

Make sure you address these circumstances in your math .

4Johnpipe

Funny video...not entirely accurate but close. To the OP yes you would size for all equipment at full fire and you would need a larger gas meter.

Kjmass1

Thanks- sounds like a tank is the easiest way to go. It sure doesn't look as cool though.

Rich_49

Don't be too sure . This should cost about the same installed , if not a bit less . Certainly will save you more scratch all things considered .

http://www.htproducts.com/phoenixldwaterheater.html

SWEI

Out here in hard water country, we see plenty of real issues with tankless heaters. Still, they do have their uses. We happily specify and install them when they do make sense. Our primary job is to make sure the customer makes an informed decision.

njtommy

Lol that's awesome.
Great video

Koan

I love that video - but how accurate is it?

John Mills_5

May not be all accurate but I think people are going into them expecting that they are saving a bundle when they aren't. Also they aren't factoring maintenance in nor are they factoring in a possible very pricey repair out of warranty which would more than kill any savings. Spending $1500 more for a tankless over a standard tank install to save $50 a year doesn't make sense and that is likely rather accurate. Like up here in a cooler climate buying high SEER A/Cs. Spend $500 premium to save $20 a year.

bob eck

You are professional contractor be it a plumbing contractor or a Heating / HVAC contractor that is selling water heaters you need to talk with the home owner and see what their hot water needs are. Ask the home owners do they run out of hot water? How many people in the house? When are showers taken? All in the morning? All at night? Some in morning some in the evening? Do they have teenagers that take extra long showers and then you jump in and there is no hot water for them? TGWH as well as tank type water heaters have their draw backs. Selling tankless gas water heaters on energy savings alone is not the complete story . I would sell TGWH on that if sized right and installed right they should never run out of hot water. With yearly maintenance they should last 10 to 15 years or longer.