Thanks Mike. I just installed a second unit using your piping method yesterday and it worked great! Interesting thing to note is that when you display the GPMs on the panel, they are evenly split. When I tested the new Rinnai, I had the old one off. I didn't shut off the hot and cold water inlets to the old one so when I ran water I was only getting half the GPMs through the new unit and it wasn't getting hot enough. As soon as I shut off the old one's shutoff valve, the new one had all of the flow and worked great, which makes sense. Only reason I am mentioning this is that if you do have two units that are piped this way and one fails, the technician needs to make sure they shut off the water flow to the one that has failed because if not, the pressure is split whether it is on or not. Thank you for posting your video. My client was better served by it.
Thanks for the video. I have seven units in parallel. I will check them to see how they are piped. Looking forward to the upcoming communications video.
Thank you Mike. Great topic. Correct me if I am wrong but “first in last out” is for non build in recirc pump units only with external pump and aqua stat system. RUR models do not apply. Thank you
Can I get a drawing of how to do this with a dedicated recirc line do I have to put spring checks before both cold feed or do I have to spring check each tankless individually
You mention a video for the correct way to install and set up the EZ-connect cable between 2 RU units. I couldn't find it. Can you provide a link? Thanks
Rinnai says differently for a two unit set up, one RXP and one RX. They sent me a pipe schematic, and it’s not only first in, first out, but the first in unit is the one without the pump. I’m going with Rimnai’s pipe schematic, because if something doesn’t work right, or something gets fouled up, I’m pretty sure “That Tankless Guy” isn’t going to warranty my customers $6000 in water heaters. No offense to you Sir, You are indeed an angel for all your selfless help to other people out there. 😎
Great video! I have a single unit with a recirculation line. However, when I hit recirculation on the phone app, nothing happens. I know it's connected since I can adjust the temperature from the phone. I checked the parameter settings and confirm that it's set to 4b (recirculation settings = dedicated). I checked the other settings and noticed that the default for "units in standby" is set to 07A = 2. Does this mean that it things there are multiple water heaters?
943 pm I have a salon with 2 tankless water heaters. I checked the heaters one runs 3 sinks. O problem. The other runs 12 sinks and cannot handle the load. Can I twin them to Run simultaneously?
Hey I have a home that has 2 Rinnai RU199iP in parallel , The previous homeowner did not have them connected to control each other. What parts would I need to fix this. They run erratically as is .
I have an 2005 R53, we ran out of propane, once filled unit throwing code 11, I am assuming there is air in the gas line..can you explain how to bleed the gas line. please 🙏
This was incredibly helpful. My question is with the ez connect. Do I need to change the parameter 7 for the primary the sub or both? Thank you very much!
My Rinnai HD200e stops operating the display screen coming on and then goes of after few seconds. What is the problem? I have cleaned water inlet filter, there is no error code on.
What determines first in and last out? I think I see "first in" as shortest pipe length from shared cold water supply and "first out" as shortest length toshared hot water exit.
Thanks for the explainer video. Question: if I have two weak, electric tankless heaters (one can't get the water hot enough for showers during the winter), then why not run it like this: COLD IN on Heater #1, HOT OUT from #1 to COLD IN #2, HOT OUT from #2 ? Why isn't this an option?
Hi Mike, i flush rheem and rinnai heaters, trying to flush a double heater (side by side) the left one will not flush, it has its own set of servicing valves, but when i isolate water or cleaner will not cycle.
How’s it going! It’s mike from Agustin Inn. I’m about to try and repipe our hot water heaters! Any suggestions on how I should route it? You might remember me, I remember you Informed me of the first in last out a few months ago! Thank you sir!
Hi, how are you Mike ? Your videos are great. I installed 6 Rinnai units. I just have a question that I couldn't find in your videos. For the gas installation for 6 or more units, the gas company recommends one thing, the boiler companies one thing. I'm a little confused as to what the correct way actually is. The gas company says that with two regulators outside the house and a direct line it is fine, other videos say that the regulator should be installed 4 feet from the tankless inlet. The boiler company says that 1 inch pipes are fine to feed 6 tankless water heaters and the gas company says that it should be 2 inches in the tankless area and 1 inch underground. Thanks
What about a 3 story home with 1 cold water supply, and 1 dedicated tankless for each floor with no recirculating until? How does that get plumbed ? (Electric not gas?)
Great video! Makes perfect sense. Is it possible to use a Rinnai tankless on a hot water line coming from a regular tank hot water heater? I have a large home and with multiple bathrooms but live alone. My tankless is right outside my master bathroom but I also have a regular tank water heater on the far opposite corner of the house. I was hoping to accomplish two things: (1) Have the tankless kick on so I had hot water instantly (for example - when washing hands) and (2) have potentially endless hot water when the tank runs out for the 3 rain maker shower heads in the shower.
Thank you for the video - I am a homeowner and constructing a new home and planning to have a dedicated RUR199iN for the master suite only, but in the winter (in New England) if the GPM demand cannot keep up with the unit due to the temperature change, would it be difficult to use your technique in this video and plumb in a second unit after the initial install of the first unit? The second unit probably won't be needed in the summer. Is there a way to change from using one unit to two, and vice versa easily? Should I plan for the possibility of needing a second unit in the roughs now? The unit is located in an unfinished storage area in the basement, in case that matters. Thanks for your advice on this!
Hey Mike, Could I send you a couple pictures of a system I just replaced with a bank of 6 RE199ip's and get your opinion? It's a recirculating system with two storage tanks. Aquastat in tank turns on pump which fires all the units at once. I'm curious what the opinion is on this setup vs first in last out ?
Why doing it this way? And not just run separate dedicated hot and cold lines for each WH supplying different areas of the house? For example 1 wh 1sr floor and 1 WH 2nd floor?
Off topic, but i have been doing service on alot of tankless Rinnai in a development. all the homes have a short vent horiozontal application, that terminates horizontally. Have had alot of complaints about HEAVY vibrations on high flame needs. . and by heavy, i was able to recreate it, and boy ill tell you it was very noisey and the unit shuttered hard. it eventually code 12. put on the monometer was reading 7 at inlet and used guide to force low fire numbers, when trying to adjust high fire it would shutter sound like a trumpet and code 12 never being able to set it. the builder is putting storm caps on the vent termination outside, which is causing the issue, exhaust and intake mixing. not sure if you have covered that kind of problem on a heater, but somthing simple had me scatching my head as the weatherhead looked OEM.
Hi Mike, I am tracking down what I believe is a plumbing issue. I re-did the water piping for "first-in, last-out" as you recommend. Now with only one faucet on, neither water heater fires. With two or more faucets on, both water heaters fire. My house was constructed in 2007 with both a R53 and a R85. One is a back-up, but i would like to have both on the system for greater demand. Looking at some of the multiple tankless installation literature I see the use of a Pressure Activated Valve on the second tankless water inlet. This was not in your plumbing video, so before I purchase one, I wanted to run this application by you. What do you recommend? Thanks,
Hi Mike, i have 3 tankelsss water heaters piped the way you have them and were working fine till about 2 weeks ago after working well for 3yrs. When hot water is called for, one of the units turn on, but the water goes from hot to cold, to warm, and then slowly gets back up to temperature if kept running. I called the manufacturer to troubleshoot the units and was told that they are all working well and that the issue might be the lack of a check valve being put on the cold line. I'm inclined not to buy the idea because they were working well till recently, and i cant figure out what the issue might be. Maybe one of the flow sensors from the other water heaters isnt working and is letting cold water run through its line when another water heater is working? Have you ran across this situation before?
you never explained WHY WHY do first in last out, i know you said the other one will fire first but WHY DOES THAT MATTER WHAT issues will you experience if you don’t please explain the reason
The whole loopdy loop is Not the correct way to do it. If you want to do it right you have to manifold it so once you tee off to each heater the lines are the same length so that they have the same amount of draw. It still won't work right with the loops. Just like with multiple body sprays in a shower
You talk too much.. why only paint red half the hot pipe ? What does it get cold at the coupling ... I'm better off to Google image a diagram for tandum tankless or piggyback tankless HWT
Thanks Mike. I just installed a second unit using your piping method yesterday and it worked great! Interesting thing to note is that when you display the GPMs on the panel, they are evenly split. When I tested the new Rinnai, I had the old one off. I didn't shut off the hot and cold water inlets to the old one so when I ran water I was only getting half the GPMs through the new unit and it wasn't getting hot enough. As soon as I shut off the old one's shutoff valve, the new one had all of the flow and worked great, which makes sense. Only reason I am mentioning this is that if you do have two units that are piped this way and one fails, the technician needs to make sure they shut off the water flow to the one that has failed because if not, the pressure is split whether it is on or not. Thank you for posting your video. My client was better served by it.
That’s correct and also unplug the MC cable. Thanks for the comment Mike
Thanks for the heads up!
Crazy we just did this on a three tankless set up and works perfectly ... Thanks Mike.
Great to hear it.
It's a great video! Thank you. I"m looking for my grand kids who are in the hvac trades!
Thanks for the video. I have seven units in parallel. I will check them to see how they are piped. Looking forward to the upcoming communications video.
Mike this is a great video, I will remember FILO if we decide to run two units. Thanks for taking my call today and giving me great advice!
Great job you explained it very good. Thank you.
Wow, ty man. Hope I can keep up. You're very good
Great videos and congrats on the 10k sub 🙌
hey mike , this same water configuration works on navien tankless ?
Man, I am not a plumber, I love this type of work, you are a legend!
Thank you Mike. Great topic. Correct me if I am wrong but “first in last out” is for non build in recirc pump units only with external pump and aqua stat system. RUR models do not apply. Thank you
Hi Mike, you video is extremely helpful. I was wondering how to incorporate a holding tank to a double rinnai system
First you need a storage tank with three tappings. You need to have a pump pump into the tank from the tankless heaters.
Can I get a drawing of how to do this with a dedicated recirc line do I have to put spring checks before both cold feed or do I have to spring check each tankless individually
You mention a video for the correct way to install and set up the EZ-connect cable between 2 RU units. I couldn't find it. Can you provide a link? Thanks
I had to take it down because there was trouble with them
Rinnai says differently for a two unit set up, one RXP and one RX.
They sent me a pipe schematic, and it’s not only first in, first out, but the first in unit is the one without the pump. I’m going with Rimnai’s pipe schematic, because if something doesn’t work right, or something gets fouled up, I’m pretty sure “That Tankless Guy” isn’t going to warranty my customers $6000 in water heaters. No offense to you Sir, You are indeed an angel for all your selfless help to other people out there. 😎
Great video
Great video! I have a single unit with a recirculation line. However, when I hit recirculation on the phone app, nothing happens. I know it's connected since I can adjust the temperature from the phone. I checked the parameter settings and confirm that it's set to 4b (recirculation settings = dedicated). I checked the other settings and noticed that the default for "units in standby" is set to 07A = 2. Does this mean that it things there are multiple water heaters?
Is this the same for any water brand water heater?
I am installing two Rheem Performance Platinum 11 GPM Natural Gas High Efficiency Indoor heaters. What do I need to control them?
943 pm I have a salon with 2 tankless water heaters. I checked the heaters one runs 3 sinks. O problem. The other runs 12 sinks and cannot handle the load. Can I twin them to Run simultaneously?
Hey I have a home that has 2 Rinnai RU199iP in parallel , The previous homeowner did not have them connected to control each other. What parts would I need to fix this. They run erratically as is .
I have an 2005 R53, we ran out of propane, once filled unit throwing code 11, I am assuming there is air in the gas line..can you explain how to bleed the gas line. please 🙏
I have only one unit and the hot goes to a manabloc. What is the advantage of adding a second unit? I don't know the advantage. Please explain.
This was incredibly helpful. My question is with the ez connect. Do I need to change the parameter 7 for the primary the sub or both? Thank you very much!
Yes you do have to set the dip switches for the primary and subs
Very informative
what does a c-4 15 code mean the unit keeps turning? off and needs to be reset. thank you, Jim
What model number Rinnai do you have?
@@ThatTanklessGuy R75LSi
My Rinnai HD200e stops operating the display screen coming on and then goes of after few seconds. What is the problem? I have cleaned water inlet filter, there is no error code on.
What determines first in and last out? I think I see "first in" as shortest pipe length from shared cold water supply and "first out" as shortest length toshared hot water exit.
Does this work the same with ELECTRIC tankless heaters?
It worked with any type of heater
Thanks for the explainer video. Question: if I have two weak, electric tankless heaters (one can't get the water hot enough for showers during the winter), then why not run it like this: COLD IN on Heater #1, HOT OUT from #1 to COLD IN #2, HOT OUT from #2 ? Why isn't this an option?
Mike this is a great video, Muchas gracias , puedes Hacer un video flushing un water heater tankles rinnai
I really enjoyed the video. I have a question on the return line for my 2 tankless cu199en setup. How can I reach you?
Hi Mike, i flush rheem and rinnai heaters, trying to flush a double heater (side by side) the left one will not flush, it has its own set of servicing valves, but when i isolate water or cleaner will not cycle.
Same issue with me did you find a solution?
How’s it going! It’s mike from Agustin Inn. I’m about to try and repipe our hot water heaters! Any suggestions on how I should route it? You might remember me, I remember you Informed me of the first in last out a few months ago! Thank you sir!
Thank You!
Hi, how are you Mike ? Your videos are great. I installed 6 Rinnai units.
I just have a question that I couldn't find in your videos. For the gas installation for 6 or more units, the gas company recommends one thing, the boiler companies one thing. I'm a little confused as to what the correct way actually is. The gas company says that with two regulators outside the house and a direct line it is fine, other videos say that the regulator should be installed 4 feet from the tankless inlet. The boiler company says that 1 inch pipes are fine to feed 6 tankless water heaters and the gas company says that it should be 2 inches in the tankless area and 1 inch underground.
Thanks
What about a 3 story home with 1 cold water supply, and 1 dedicated tankless for each floor with no recirculating until? How does that get plumbed ? (Electric not gas?)
If you have 2 units, one with a pump and one without. Which unit gets the first in last out?
Did you ever get an answer to your question? I am about to install a pair.
Great video! Makes perfect sense. Is it possible to use a Rinnai tankless on a hot water line coming from a regular tank hot water heater? I have a large home and with multiple bathrooms but live alone. My tankless is right outside my master bathroom but I also have a regular tank water heater on the far opposite corner of the house. I was hoping to accomplish two things: (1) Have the tankless kick on so I had hot water instantly (for example - when washing hands) and (2) have potentially endless hot water when the tank runs out for the 3 rain maker shower heads in the shower.
Thank you
Thank you for the video - I am a homeowner and constructing a new home and planning to have a dedicated RUR199iN for the master suite only, but in the winter (in New England) if the GPM demand cannot keep up with the unit due to the temperature change, would it be difficult to use your technique in this video and plumb in a second unit after the initial install of the first unit? The second unit probably won't be needed in the summer. Is there a way to change from using one unit to two, and vice versa easily? Should I plan for the possibility of needing a second unit in the roughs now? The unit is located in an unfinished storage area in the basement, in case that matters. Thanks for your advice on this!
1/ How many bathrooms will be in your house
2/ would you know what the ground water temperature is of you cold water.
Mike
Hey Mike, Could I send you a couple pictures of a system I just replaced with a bank of 6 RE199ip's and get your opinion? It's a recirculating system with two storage tanks. Aquastat in tank turns on pump which fires all the units at once. I'm curious what the opinion is on this setup vs first in last out ?
Why doing it this way? And not just run separate dedicated hot and cold lines for each WH supplying different areas of the house? For example 1 wh 1sr floor and 1 WH 2nd floor?
Why don't you do other videos besides water heater and NASCAR?if that could be a thing I would love to see some common commercial plumbing job videos!
Hey Mike. How can one get ahold of you directly say per email? Thanks for what you do from a fellow plumber.
How about with a research?
Off topic, but i have been doing service on alot of tankless Rinnai in a development. all the homes have a short vent horiozontal application, that terminates horizontally. Have had alot of complaints about HEAVY vibrations on high flame needs. . and by heavy, i was able to recreate it, and boy ill tell you it was very noisey and the unit shuttered hard. it eventually code 12. put on the monometer was reading 7 at inlet and used guide to force low fire numbers, when trying to adjust high fire it would shutter sound like a trumpet and code 12 never being able to set it. the builder is putting storm caps on the vent termination outside, which is causing the issue, exhaust and intake mixing. not sure if you have covered that kind of problem on a heater, but somthing simple had me scatching my head as the weatherhead looked OEM.
Hi Mike,
I am tracking down what I believe is a plumbing issue. I re-did the water piping for "first-in, last-out" as you recommend. Now with only one faucet on, neither water heater fires. With two or more faucets on, both water heaters fire. My house was constructed in 2007 with both a R53 and a R85. One is a back-up, but i would like to have both on the system for greater demand.
Looking at some of the multiple tankless installation literature I see the use of a Pressure Activated Valve on the second tankless water inlet. This was not in your plumbing video, so before I purchase one, I wanted to run this application by you. What do you recommend?
Thanks,
Hi Mike, i have 3 tankelsss water heaters piped the way you have them and were working fine till about 2 weeks ago after working well for 3yrs. When hot water is called for, one of the units turn on, but the water goes from hot to cold, to warm, and then slowly gets back up to temperature if kept running. I called the manufacturer to troubleshoot the units and was told that they are all working well and that the issue might be the lack of a check valve being put on the cold line. I'm inclined not to buy the idea because they were working well till recently, and i cant figure out what the issue might be. Maybe one of the flow sensors from the other water heaters isnt working and is letting cold water run through its line when another water heater is working? Have you ran across this situation before?
How do I email you Mike ? Thanks
Economyplmbg@aol.com
you never explained WHY
WHY do first in last out, i know you said the other one will fire first but WHY DOES THAT MATTER
WHAT issues will you experience if you don’t
please explain the reason
Do you have email? I’d like to send you a picture and get your input on a double install.
Wonderful sir🫡🫡
I'm getting ready to install two tankless water heaters for the first time can you send me a drawing
I just printed and color coded a Rinnai rack system, and it is not piped first-in, last-out!
Not enough inlet flow to turn on either
reverse return
Im more confused than before I watched this
The whole loopdy loop is Not the correct way to do it. If you want to do it right you have to manifold it so once you tee off to each heater the lines are the same length so that they have the same amount of draw. It still won't work right with the loops. Just like with multiple body sprays in a shower
You talk too much.. why only paint red half the hot pipe ? What does it get cold at the coupling
... I'm better off to Google image a diagram for tandum tankless or piggyback tankless HWT
try editing your videos
Need your email