An elephant is a mouse designed by a committee - some work turning into complete replacement? - NO!

[Dana]

New info! I found a good local plumbing company with almost 400 good reviews on Google, which is EXTREMELY rare. Their tech came over and did a free estimate and gave me a bid of $913 for all the work, which included replacing the plastic drain faucet with a brass drain faucet, replacing that T that was going to the mixer with a cold water shut off valve for the water heater, removing the mixer, and a draft hood and expansion tank.

So the actual plumber came over to do the work today, and looked at the water heater and said that there's a reason that there was no draft hood. It turns out that this is a mobile/modular home water heater, which is smaller, to fit the cabinet space and has less BTU's, and it has a intake vent at the bottom of it. Ahah!

He also said an expansion tank is not a necessity, and redid our bid for the rest of the work, down to $360 now. He's out there doing it as I type this.

Interesting.

Glad I didn't try to replace that plastic drain valve myself. It broke off and he knew how to get it out and get it done.

You'll note that the model number (requested multiple times) would have cleared up the draft hood issue very quickly.

I'm glad the tech was able to point out that it has an air intake that extended below the floor. While the BTU rating of the burner is only ~20% lower than a typical "standard", and doesn't have a whole lot of bearing on this. The primary factors are that it is sealed combustion/direct-vented, with limited stack height.

There are very few direct-vent atmospheric drafted water heaters in the world, but apparently Rheem makes one of them (or rather two, a 30 gallon and a 40 gallon). With sealed combustion any flame rollout from a backdraft on this series goes down the air intake, designed to extend sufficiently below the floor to not be a fire hazard. From an appliance design point of view, to keep the combustion air in the right range there are height limitations spelled out in the is a presumptive minimum & maximum height for the stack in a manufactured home that would not necessarily be true if installed in a (potentially) multi-story home, or even a 1-story home over a vented crawlspace and a high roof pitch.

 

[Melissa2007B]

You'll note that the model number (requested multiple times) would have cleared up the draft hood issue very quickly.

I actually posted it on page 2 of the thread: Anyway, it's a RHNGQ131303279, according to his invoice. I don't see any reference on the web, for the proper draft hood for that one.

 

[Sponsor]

 

[Dana]

I can't even find a water heater with the model number RHNGQ131303279 on the web (can you?) That looks more like a serial number not a model number. Plugging that number into Rheem's manufacturing date by serial number web tool indicates it's a valid serial number, and that it was manufactured on 03/26/2013 (does that seem credible?) Reading the model number off the label the water heater is more reliable.

The current Rheem model numbers are XG40T06MD30U1 (for the 4o gallon), or XG30T06MD30U1 (30 gallon).

 

[Melissa2007B]

I can't even find a water heater with the model number RHNGQ131303279 on the web (can you?) That looks more like a serial number not a model number. Plugging that number into Rheem's manufacturing date by serial number web tool indicates it's a valid serial number, and that it was manufactured on 03/26/2013 (does that seem credible?)

YES. Remember that this is one of the few water heaters made for mobile/modular homes and that they're rare, per one of the posts in this thread. It makes all kinds of sense, in light of that, and the fact that we had it installed in 2013 by that guy who turned out NOT to be a plumber.
...
( I just went and looked on the water heater and that IS the serial number. )