I am replacing my tankless HWH soon. I have a few questions related to the new unit. 1. My municipality provides 7 CW natural gas pressure for my residential line. If I buy a tankless HWH that is rated for 8 CW, will it run? 2. How often do I REALLY need to descale the tankless HWH with white...

Can someone share a drawing of a installation using the following components : 1. Tankless GAS water heater. I have a RHEEM - (No Re-circ included) 2. Re-circulation pump. (Grundfos) 3. Return Line, Cold Line and Hot water line. 4. Check valve (back-flow preventer) Please advise best way...

I am in the process of installing a natural gas-powered outside tankless water heater. It's a small house, so I want it installed on an exterior wall to save space inside. The issue I'm running into is clearances around the heater. I have a very small spot where it can be installed on the back...

I want to install a tankless water heater in my house, so I'm practicing soldering copper on some scrap pieces. I may have to reroute copper water lines in the crawlspace to the heater location on an outside wall, so I want to make sure I get this right before making trouble. I used a mini...

Hello all! Trying to clean/descale an ELECTRIC tankless water heater. Model is a Bosch PowerStar AE125. Trying to clean/descale the mineral deposits that build up inside virtually all tankless water heaters. Admittedly, it has been a while, probably 2 -2.5 years. (Yeah, I know, I know...

I have a Rinnai RUR199en tankless water heater. For maintenance I need to flush it with vinegar about once/year using a bucket of vinegar, 3/4" connection hoses, and a submersible pump. Rinnai won't recommend a pump to use for this operation. They only recommend that it push just 4GPM. The...

Navien CR-A 240 Tankless Hot Water Heater installed in 2010. Making an unusual clicking sound as heard in linked video. Has anyone heard anything like this? Sound appears to be coming from inlet flow adapter/flow adjustment valve/flow adjustment v/v pipe. Noise begins at 00:15 (sec) in video...

I have a Rennai tankless water heater. The pipe-in-pipe dual exhaust pipe runs through a conditioned crawlspace, then outside through an exterior wall. The outside temperature is currently 26 degrees Farhenheit with 25% humidity. The inside temperature is ~74 degrees, and 43% humidity. I've...

I live in Sacramento, CA and I am in the market to replace my 14 year old gas water heater. It is a 75 gallon direct vent gas water heater that is situated in our garage. Due to the new 2105 energy regulations, we cannot get an exact replacement of our previous water heater. We have had 3...

I have a recently installed Rinnai RU801 Tankless Water Heater. The WH was installed with the concentric vent option. The WH is mounted on an interior wall, and the vent goes directly to a 90 degree elbow, then slopes UP to the exterior wall over about a 10 foot distance, then 90s up, second 90...

Hello All, Im new to this forum and have a question - Can anyone comment why is there black soot (or black specks) that could be coming from coming hot water line? Client lives in Chicago area, Eternal Tankless waterheater model GU145S installed December 28 2010 (2.3 years ago). Background -->...

Where would you put water hammer arrestors in this situation: 1 2 or 3? If 2 or 3, I would use a 90 to ensure the arrestor is vertical. The Bosch is vibrating when turning on the hot water heater; it, too often, errors out causing me to reset the heater. After researching this, it seems to...

Where would you put water hammer arrestors in this situation: 1 2 or 3? If 2 or 3 I would use a 90 to ensure the arrestor is vertical. The Bosch is vibrating when turning on the hot water heater. After researching this, it seems to be common with this water heater model.

I have an electric tankless water heater that is curently fed from the hot water (potable) return line of my boiler. So hot water is getting heated from my boiler and again through my electric tankless water heater then distributed throughout the house for drinking and showers etc. Is this a...

Looking to install this in the new house. 5,500 sqft - bathrooms(7)/kitchen are spread out. My plumber said 1 will supply enough hot water and is an Eternal Hybrid fan. Anyone out there have/installed the Eternal Hybrid? Feedback good/bad?

I am thinking about replacing my water heater(died) with a tankless water heater and have a quick question about piping size. My house is piped with 3/4 inch PVC piping and the sales men at my local hardware store said the tankless water heaters they sell are 1/2 inch input and output. My...

Hello, We have a Rheem RTG-53PVN tankless water heater. Last night washing dished the hot water suddenly went cold. Went downstairs to find the heater off with no power. Checked the circuit and that was fine, and the outlet is working fine as well. any suggestions on what might be wrong? Is...

Hi everyone, We live in a house that we built new two years ago and have a pair of Rheem RTG-53PVN tankless water heaters installed that we have had no problems and the water comes out as hot as the day we got the units. A week ago, we got two codes displaying on the separate LCD display. The...

Sharing my recent experience. We had a 75 gal gas fired hot water heater leak. Went to store with intention of replacing it with new tankless system. Cost of tankless including equipment and install from $3800 to $4300 (got 4 difference quotes). And federal rebate calculation which has a very...

I have just moved into a brand new house. It's a 3 storey house with the bottom storey being a kinda basement (even though this bottom storey is above ground) with the other 2 storeys being the regular 2 of a traditional 2 storey house. The house has a tankless water heater that is located in...