Heating Help

Rinnai tankless woes

Friend has a residential Rinnai that will run fine, but within 2 minutes of operating, it stops and then starts up again.. It's not a flow problem and we have changed the flow sensor.  City water.  Screens clean.  Backflow cleaning performed twice.  Tech support not friendly.  Gas (NG) pressure fine. Any ideas?  Thanks.

Try this...

I represent Rinnai. For info, who did you speak with at Rinnai? Case# What error codes are you getting? Pull the immersion sensors on the upper rt and at the hot water exit of the unit. It is the 1/8" ss sensore in the well connected with two white wires. Two small phillips head screw. There is an O-ring in the well. Sometimes it stays on the sensor, sometimes in the well, sometimes you don't see it fall to the floor . Is the sensor coated? Sounds like you have climbing temps and it is tripping on limit. Does the unit restart when temps drop? Read the output temp on the unit (push down arrow for at least two seconds and then while holding the down arrow push the on/off button )and monitor the output temps. Are there any indications of condensation coming back to the unit. If there is any debris in the hx fins. You can check by removing the flame rod and sparker. Get a light look up into the bottom of the hx fins. Remove the vent and examine top of the hx for same. If condensation has come back onto the hx and cooked off it will leave a residue which inhibits the the flow of flue gases, which can increase water temps. If a Rinnai exceeds its set-point by 6F it will shut down and restart when temps come down. In this condition it will not generate an error code. It is possible that the gas valve may be malfunctioning, but I'd look elsewhere first.

Have you flushed the heat exchanger? Have you tested the water for composition? Where are you? If you'd care to chat about it, I'm at 617 834-8751

First things first

What is the Rinnai being asked to do? Domestic water heating? Space heating? Is this in a house or on a commercial site? What size is it? How long has it been in use; has it ever ran properly? What did the water sample tests reveal?

How did you make out with this?

You have a problem, questions are asked, help offered! You throw tech service under the bus and after 5 days don't respond. How are you doing on this? Is your friend okay? What was the fix?

Rinnai Issues

Kneedeep:  listen to Jack....I've known him for years and he's one of the very best. If he can't help you fix it, it's broke !!!!
Good luck.

tech

I have installed many of the rinnais and have had only one problem and that was my fault....When I did call for advise I was treated very well and tech guy was knowledgeable   j a

tech

I have installed many of the rinnais and have had only one problem and that was my fault....When I did call for advise I was treated very well and tech guy was knowledgeable   j a

Rinnia issue

I have installed a Rinnai RC98. Model back November 2011. And now ther is this problem with the nit after only 6 month of the install. The unit does not ignite - it gives me the error code 12 which means failur to ignite - and on the manual I follow up at the trouble shooting paper across that error 12 everything that ask me to check I have done / gas pressure is good venting good - power is ther everything seems in good conditioning. I have called the Rinnia tech Several time but no help what so ever. .. The unit wich just give me error code right a wake while trying to run it .
And sometimes only sometime it would work just be punching the on off button ! But that sometimes.

Any help tip will be helper !! Thanks in advance

When you get into

This type of situation where you feel you are not getting help from tech service you need to do two things. Ask for a service "supervisor". As well, this is when you get your local manuf representative involved. Call them and get them out there. What is your case number?

Scanning down the list of posts I was delighted and saddened to see a post from Al Letelier. What. Fine man! I miss Al!

C'mon man,

You post with a problem where you are getting no help...and disappear! What is going on? Is it fixed? What is/was the problem?

No Reply:

Don't worry about it. It happens all the time to me.
Just remember, there are people that follow this site that suck vast amounts of information from it. Like myself. Sometimes, the question that is answered (or not) is the question that solves a problem for another.
Good informative help is hard to get or find. Myself, sometimes, I need to hear myself talk to solve the problem. Sometimes, Tech Support isn't what we would like it to be. Sometimes, tech support gets burned out by stupid questions that a first year hackaroo should know the answer to. Sometimes, I've dealt with Tech Support with a difficult problem and when the tech support person realized that I knew what I was talking about and had far more knowledge than most who called, it became another call. Where we could diagnose the problem properly. I had already covered all the bases.
Your post from a year or so about the sensor and the O-Rings can be a help. Don't get discouraged.

Thanks for that Ice...

But the lack of response is not discouraging me. It does however piss me off. I think that if you decide to drag up an old post I just think it is respectful and polite to follow-up. I get what you are saying though.

Again, it did and has given me the opportunity to remember Al, so maybe I shouldn't complain. Thanks for the kind thought Ice!

Same problem

I came to this post looking for help with the same issue with my Rinnai. The first unit we had installed malfunctioned after only a few months, giving error code 14. This continued on and off for about a year without an actual cause being found. I pushed and got the installer to pressure Rinnai into sending a replacement unit as this one was obviously faulty. The new unit worked like a charm for about a year and a half, providing hot water for the two units in my house (the main + suite in the basement with tenants). Last November (2012) this new unit started glitching, this time giving the error code 12 (flame failure). The installer came, cleaned the burners and water intake filter (hardly had anything noticeable in there) and couldn't repeat the error. So, problem fixed. Or so he thought. A few weeks later, same error code. He went through every step in the manual, checked everything that could cause this error and came up empty. As the unit failed to show the error while he was on site, Rinnai also could not help the installer figure it out. I was told by my installer to call them when the error was on the unit... which of course only happens on weekends or late at night and they are charging higher rates to come out. It errored again last night and is still glitching this morning, so I'm once more waiting for the tech to come out. Any help or advice into this problem would be greatly appreciated.

LP

Is this unit on propane? If this unit is on propane your regulator might be freezing up if its going out when it's real cold outside. Contact your supplier and get them to come out and change the regulator and set the gas pressure that will give you a baseline to start at.

Gas line sizing?

Has anyone looked at you gas line sizing and pressure? All to often these are installed to replace tank hot water heaters with much lower BTU requirements. Everything works OK until other appliances on the line turn on. The gas pressure will then drop and cause an error.

Rinnai engineer coming

Aaron, it's not on propane, so it's not that. But thanks for the suggestion.
Zman: I had my installer come and check everything several times on this issue already. They did come out on Monday and luckily the error code was displayed. Nothing was found out of the ordinary. The installer has now put in a call to the Rinnai engineer for our area and hopefully he will be able to come down within a week. Fingers crossed. I'll let you know what they find.

Rinnai

Checkout the thread below titled rinnai r53i-1. The symptoms sound the same. Just have it around when your tech and the rep show up. Might help

Something to look at.

Check your vent termination and the joints on the vent. Is it clear around the vent termination? It is possible that a condensing unit, garbage can, etc may be impacting the vent and re circing exhaust gases. Perhaps one of the joints is partially dis-lodged and in a low fire condition not cross contaminating, but under high fire flue gases are drawn into the fresh air side.

Your error code 14 on the first unit is in the safety/limits circuit. An open limit will prevent operation. That is a simple series loop and with a digital multimeter the open limit could be identified.

Tech coming tomorrow... finally

Hi guys,
thanks for all the suggestions for the tech to look into. After many calls over the past week, I have a tech coming in tomorrow to try & figure this out. It is NOT the Rinnai tech as promised by my installer, but the installer's senior guy who is going to call into Rinnai as they think they can figure it out that way. They better. I have printed your suggestions and will definitely bring them up. And I will keep you posted as to what they come up with in terms of solution.

Rinnai fixed?

The installer's tech came by today and I was able to trigger the error code for him. After running some tests and triggering it several more times, he finally thought of checking the gas pressure. Turns out, in high fire, the unit would drop below the min. requirement (dropped to 3 with the furnace also on, needs 5). So he checked the regulator which was set too low. He admitted he had not checked this before at all. Doh! After he corrected this, we were unable to trigger the error again over the span of an hour and a half.

I showed him the suggestions from the forum and he checked the vent: no condensation in the unit or in the hose that's the bypass for condensation - no blockages - no buildup in or around it - no dislodged joints. So, should be fine. Gas pipe is 3/4" so also fine. Water is only 1/2" through the house, but 3/4" at the unit. As the unit has worked fine for almost 2 years, he didn't think that could be the issue.

I was not charged for this visit (and he also fixed my drain while we were running the tests to re-trigger the error!), which was pretty decent I think.
If this is not the fix, I'll keep the forum posted. If you don't hear anything, it's fixed. Here's hoping I don't have to post again. :-)

Gas Pressure

Although it defiantly sounds like low gas pressure was the issue, you may now have other problems. If your gas piping is sized correctly, with all the appliances in your home firing you should not see a significant drop in gas pressure. By increasing the pressure at the regulator to accommodate the tankless heater, he has now increased the pressure to all of your gas appliances possibly changing the combustion characteristics of them. Your gas pipe sizing needs to be checked! Can you post pictures of the gas piping, regulator(s) and give the distance and BTU ratings of the gas appliances in the home? Everything COULD be OK, but I doubt it.
Rob 

Gas pressure check

Hi Rob,
Gas pipe is 3/4". Regulator is close to water heater. Furnace is right next to water heater. Stove & fireplace on main floor are the only two other gas appliances in the building. Your input gave me cause for concern so have contacted a different plumber that was recommended to me to come over for a second opinion and double check on this. I'll post my feedback on here as well. Greatly appreciate you taking the time to provide input.
Ellen

Glad to hear its fixed

So once again
1. A manufacturer replaced a unit when it wasn't the units fault
2. The initial installer didn't do his homework, was not a competent or skilled installer and was not able assure the full install was correct
3. Extensive labor, costs, various people involved, some that shouldn't be because they don't know what their doing
4. Manufacturer does the best they can with the limited info provided and must trust the techs on site to know what their doing.

In the end, nearly another black eye for the tankless and appliance industry, and it wasn't their problem - another sad day for those that do have the proper skills & the manufacturer that lost the most in the end.

Gas Pressure

Hmmm:  As gas pressure is so important for tankless heaters, I wonder how difficult it would be to have a "low gas pressure" error code?  It would make life easier for everyone but the installer who didn't pay attention to gas line sizing.

Yours,  Larry

Error Code 25

Well I just had a Rinnai RC80E installed in Tampa, Florida. I must admit the concept takes a bit getting used coming from a 40 gallon natural gas. However, since the unit has been installed the error code 25 has been coming on. I've read the manual regarding the condensate trap being full and to empy. I've done this and still the same issue. On the bottom of the unit I've a manual screwable plug, another clip type plug, and a 3rd plug which has a black rubber cap that comes off. I contacted Rinnai and their customer service is something left to be desired as they were no help. Any help here in the form would be greatly appreciated, as I am really wondering if these units are what they say they are. Delays from the unit to the service points ( I question effiency at this point as cold water is wasting as you wait for the hot water) Anywhere from a minute to 2 minutes waiting. Then the error code kicks in while your in the shower turning the water cold while all soaped up !

Error Code 25:

I remember a conversation with someone who services a lot of stuff. He had a huge problem with one of these (I think it was one of these) and it was a problem with the attatchment of the condensate drain assembly, He went through agony finding it and fixing it. Tech Support wasn't helpful unttil they got on the right track.
If you can't figure it out, post back and I wil contact him. He finds all kinds of strange problems. He doesn't install them, he just fixes them.

Rinnai fixed

Hi there,
Just thought I'd post a follow up on my story.
I had a second opinion - had different plumbers come & check the entire installation of my unit.

They found 2 errors with the installation:
1. the original installers installed a condensation hose to the top of the unit, where this is a non-condensing unit. According to the 'new' plumbers, this does not create problems, but it should not have been installed.
2. they installed a regulator on the pipe going to the water heater, which was not necessary either. It's totally superfluous now, as it's cranked open all the way as the unit was starved for gas, which created all the problems in the first place.

We have not had any issues with the water heater since the gas pressure to the unit was corrected.

The pressure on the system is fine for all the other appliances as well (new plumbers checked all that out too).

So, so far so good. Needless to say I will be switching plumbers. :-)
Thanks so much for your input on this issue. Greatly appreciate it.

Ellen

Gas supply is important

When ever I install a gas tankless, I always over size the gas line, then before we leave I always run all their gas appliances {stoves, dryers, furnaces and boilers, generators everything all at once, and let the unit go to high fire while watching the manometer, if the pressure drops too much, we have to fix it before we leave, I have had to rerun gas lines, hence the always oversizing now...

Propane brings a few other issues, the only rinnai units I ever seen sooted up were LP and 99% of the time they were being used for space heating...