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Navien Tankless and others

4K views 11 replies 6 participants last post by  Master Mark 
#1 ·
I've been installing Navien 204A and also Rheem rtgh-95dvln. I have had no issues with either, but sell more Navien because I get really good pricing on them. What are the issues y'all seeing if any, with the Naviens or Rheem rtgh-95dvln if y'all do those. I've worked on the Kiturami units and they seem nice and advanced, but they seem to be problamatic. Both Noritz and Rheem rebrand them, I'm sure others do too.
 
#4 ·
Same here with Navien, I've had good luck with them since probably 2013 or so, seems before that date they had issues, but newer models have been good for me. Same for the Rheem, been good for me too. I sell 10 Naviens to 1 Rheem though.
 
#5 ·
I have to install my first Navien tomorrow because of the tight space it is going in,,,, We were gonna install a 75 power vent but it is almost impossible to get this monster down the stairs and make it work properly
so I decided to finally try one just to see how well they really work.....

I am wondering if they are as easy as everyone claims..... Its the largest one with the recirc chamber inside it .


according to what I have read it only needs a 2 inch vent out the side of the house about 10 feet away... and it claims not to need a air intake coming in from the outside either.... (good or bad)

the gas line is a full one inch and its the first thing on the line so that cant matter too much

the only question I have is it mandatory to install a thermal exp tank on these units??? One person who has installed a number of them claims it is not necessary.....

Throwing up a piece of 3/4 plywood on the wall and bolting this unit to it next to a new water softener.....

of course I have the isolation valves to install on it

any tips to follow would be good to hear before i screw up one..

thanks

 
#8 ·
The fresh air question depends on how many cubic feet you have in the room and what other gas appliances are using that air already. All water heaters are supposed to have expansion tanks or valves. Definitely use the valve kit to make it easier to clean them out when the time comes.
 
#9 ·
They are very quiet compaired to a power vented water heater...

the home is an old barn from about 1880 and there is plenty of air available so we just put the exhaust out the side of the home......... its only 10 feet away and I might still run it outside


I got to go back due to a half assed gas line which appeared to be one inch coming over to feed a furnace, but in closer examination way behind the furnace, it was only 3/4 increased to one inch for some half assed reason, so I will have to upsize the gas line over the course of the next few weeks......I am a little peeved about this.....

The unit is the largest one the 240 with the built in re-circ feature.....

we set it at 130 and it seemed to work fine.....very quiet


it seems to me that the thermal expansion tank is optional and I dont understand where the thermal expansion would actually happen being that the water is used instantly and their is really only storage in the re-circ pump.... whatever........



.
 
#10 ·
Never install them on a bedroom common wall (noise).
I've been installing them since the old NR series. Changed out a few NR pumps under warranty.
I always use the NPE series (with buffer tank and pump).
Recently (for the last year) I have needed to get factory to send replacements for the internal check valve. They are sticking after a few years, here where we have chloramine there is a little o-ring seal on the spring check that hangs up.
Symptom is: Slight or marked uneven temperature drift. Especially in recirc situations.
Same symptom you get if you have a pressure balance shower valve with a internal defect. (Which I have encountered with Delta and Kohler).
No expansion tanks unless we have added an external pump plus check valve on giant recirc. loops.
 
#12 ·
I went to all the trouble today to install the thing with a small expansion tank on the floor, and their was a debate about whether the air intake needed to be run to the outside or it could just take air in from the basement.... It was only 9 feet away to the outside wall so outside it went....... very simple and very easy.... and its about 9 feet away from the tankless vent so I am pretty sure its just fine......

the gas line in this barn is from 1880 and their are dead abandoned gas lines branching off a 1 1/4 gas trunk line going from one end of the crawl space to the other end... This house used to have gas lights in every room and I think the lines are capped off in the walls...

. I am not gonna touch that line and risk some leak starting somewhere ....

We are gonna rip it all out next week and run a full one inch black line over to the furnace and tankless unit........ the customer is happy to upgrade the system after I showed them how nasty it really was....

You got to look over that gas issue very closely cause this one is a pain in the ass ..
 
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