Tankless venting

[Chris mclt]

I just had a tankless water heater installed. The plumber that installed it got rude with my wife so she threw him out of the house so I can't call him to come back and fix the problem. The unit works fine with the front off. If you put the front on it with in a minute of it firing it shuts off. I believe that it is starving for air. The vent is threw the roof and I believe that it is too long of a pipe and not big enough diameter. Any ideas of how to remedy this problem?

 

[Terry]

Do you have the model number and the paperwork for the tankless water heater?
How about a picture of the installation 800 pixels or less uploaded as an attachment.

 

[Sponsor]

 

[Chris mclt]

I just had a tankless water heater installed. The plumber that installed it got rude with my wife so she threw him out of the house so I can't call him to come back and fix the problem. The unit works fine with the front off. If you put the front on it with in a minute of it firing it shuts off. I believe that it is starving for air. The vent is threw the roof and I believe that it is too long of a pipe and not big enough diameter. Any ideas of how to remedy this problem?

Do you have the model number and the paperwork for the tankless water heater?

Not with me but it is a Rheem prestige 199,000 BTu indoor water heater

 

[Terry]

Perhaps this one?

https://www.rheem.com/product/profe...-with-12-year-limited-warranty-rtgh-95dveln-2

 

[Chris mclt]

I do believe that is the one

 

[Bannerman]

The specification sheet (page 2) indicates with 2" venting (exhaust and combustion air), the maximum distance will be 60' with straight pipe and no elbows, or 42' with 6- 90° elbows. Factory default DIP switch settings allow only 22' maximum distance of straight pipe so the switch settings will likely need to be changed for your installation.

With 3" venting, max 150' or 141' with 6 elbows.

 

[Chris mclt]

how do you change the DIP switch settings?

 

[Chris mclt]

He used 2" pipe with 3-90's with about 25 foot of pipe

 

[Bannerman]

I couldn't locate an Installation manual from the Rheem website, but did find this YT video which discusses this matter.

 

[Fitter30]

Are there fittings outside like a elbow or maybe two?