Rheem 95-DVLN

[Steven Kirchner]

Hello,

I'm looking to have a Rheem 95-DVLN 199,000BTU water heater installed. I've had two plumbers come out give quotes and both I've said I'll need NO modifications to my existing gas meter or gas lines. I'm kinda of taken back by this answer and was under the impression I would need a new meter from my research. Please look over what I currently have and what I'm wanting to add and let me know if these plumbers are correct.

My current meter has these numbers written on it.

250 C.F.H
W.P. 5 P.S.I
At .5" W.C. DIFF.

The gas line coming from the meter into my house is 1 1/4" and runs 25' to a 3/4" tee. There are three 90 degree els in this run. First appliance from the meter will be the water heater. After that, the 1 1/4' line runs another 8' to a 90 degree el and feeds a furnace.

The first furnace data plate states,

Input 110,000 BTU / Output 89,000 BTU

Min supply pressure 4.5 IN W.C.
Max supply pressure 13.6 IN W.C.
Max Static pressure .5 IN W.C. / POCD

After the first furnace the gas lines drops to a 1" pipe and runs 15' to our second furnace. In this 15' foot run there are two 90 degree els and one 3/4" tee.

The second furnace data plate states,

Input 69,000 BTU / Output 56,000 BTU

Min supply pressure 4.5 IN W.C.
Max supply pressure 13.6 IN W.C.
Max Static pressure .5 IN W.C. / POCD

After the second furnace the gas line drops to 3/4" and runs to the laundry room for a gas dryer, which we have electric. At some point there is another tee in the line after it drops to 3/4" and runs outside for a grill feed, which once again we don't use.

Either plumber ran any numbers and both went and looked at my meter before ringing the door bell. Both these companies have experience with installing tankless water heaters and one was very informed on the Rheem models. Maybe I shouldn't be questioning the professionals opinions but just want it install correctly the first time and not run into issues with hot water in the winter time when I have both furnaces kicking on.


Thanks for any help or advice,
Steven

 

[Master Plumber Mark]

If they are going to come off an 1 1/4 gas pipe you have more than enough gas for this tankless heater...
most times you see it installed with only a 3/4 line coming off a one inch pipe....

If it makes you feel better
just require them to install a full one inch line to the tankless off the 1 1/4 ... that would probably be close to
overkill.... but you know you got enough gas that way

 

[Sponsor]

 

[Jadnashua]

When gas comes into the house, often there are other gas fired appliances like a gas water heater, and maybe a gas fired dryer or stove. You need to account for all potential users, then add up the combined input use, then compare it to the capacity of the meter and the piping used. The gas flow decreases with size, length, and the number of changes in direction.