Rinnai E110CP explosive ignition and low heat

DonP152

Background:

I converted from forced hot water via oil to forced hot water via propane this past spring.  My installer put in a Rinnai E110CP burner which also functions as tankless hot water for domestic.

My house size is approx. 1800 s.f. single story.  I had an energy audit and they found ample insulation and adequate baseboard length and I have low E windows.<strong> </strong> I am aware that gas fired versus oil fired is different and that oil is a quicker & hotter heat, but I have a couple issues I need answers for.<strong>

</strong>

<strong>First issue</strong> I experienced and one that is most concerning to us, is that upon cold ignition, the burner basically explodes.  Very loud, shakes the house.  I've had Rinnai's N. American Boiler Service Manager at my house 4 times now and my installer's been there well over 10 times.  They've tweaked settings, ignitor gap etc... to no avail.  Finally, my installer (who's been fantastic) convinced Rinnai to replace my burner, which they did.  Unfortunately, the "new" burner had a broken plastic housing holding the computer circuit board so the re-used my old board.  Question is, Can this board be the problem as it's still "exploding" and as of late I've no success with Rinnai even answering my inquiries.  Their Service Manager even took an audio of the explosion to send to the factory but still no response.  We've tried 4 different propane supplies so we know it's not an over methanol issue.<strong>  </strong>I'm at wit's end here.<strong>  </strong>One fix which seemed to work was when the Rinnai S. Mgr added an additional metal deflector plate to the burner housing causing more turbulence of the air/gas mixture, making a better mix.  Unfortunately, Rinnai considered that an "unauthorized field adjustment" and he had to remove it.<strong>  </strong>I've been told that the Rinnai burner will expel any gas mixture if it doesn't ignite properly, but I've also been told that it's not supposed to explode like it is...<strong>  </strong>We're not real comfortable<strong>

Second issue</strong> I'm experiencing is that it takes approx 1 1/2 to 2 gallons of water flow via sink or shower/tub (no more than 20' from burner 1/2" insulated copper pipe) to get hot water.  Is this normal for a gas fired burner?  My old Burnham oil burner was easily twice as quick and twice as far away.<strong>

Last issue </strong>I'm experiencing is that even after setting the burner back to factory default, I don't get hot baseboards.  Example.  20 degrees outdoor temp.  At 4:30 AM my thermostat goes from 62 degrees F. to 70 degrees F.  My old oil burner would get the house to temp in approx 40 minutes.  With my Rinnai, at 6:30 AM, a full 2 hours later, it's still only up to 68 degrees F.  I do have an outdoor sensor which has already been replaced, but if it's 20 degrees outside, shouldn't this burner come full on and give full heat?<strong>

</strong>Any help and/or answers will be greatly appreciated.



Thanks<strong>



</strong>

Alan R. Mercurio_3

Re: Rinnai

Don, where are you located. I'd like to try and get you some assistance with this issue.

icesailor

Explosive Ignition et-al.

Think about all the money you spent to save money and you get an exploding bomb in the house. Setting off a cherry bomb in a can  in your house must really get your attention.

Back in the old days, when consumers like us had some government enforced protection, a manufacturer would have had some concern about a defective product and done something about it. With as many "eyes" that have looked at this and not found a solution says that there is something wrong with this and has a factory defect that the company should resolve. All the Rannai equipment I have heard about and seen has been very reliable. If this unit acts as you describe, the company should replace it with a new one and see if the problem goes away. If it does, then the unit you have has some defect that is difficult to pinpoint. They should have their engineers take it back and figure it out. They shouldn't be expecting we installers and technicians to be doing their troubleshooting for them. And when we come up with an idea or cause, they give us an argument. These boilers and equipment have inherent problems. Which you have described in yours. You never had those problems with your oil boiler and tankless. Too bad the salesperson/installer didn't suggest a conversion power burner in your old boiler.

There is only one cause of cherry bombs going off in a boiler. Delayed ignition. Either from the gas valve opening too soon or the igniter not working properly. Or the air fuel ratio not proper due to improper mixing.

Good luck.

don_9

Outdoor Stat

Bypass the outdoor stat that will solve your heating issue.As for the 1 1/2 to two gallon of water usage before heating up is really not bad, cheaper then a recirc loop.

Has anyone done any combustion analysis to find the reason for the delayed ignition?

We have installed several of the rinnai E110 on natural gas with no issue as of yet.But heck its a machine and they all will have some issue down the road or right out of the gate Thank goodness or I would starve..lol

Happy holidays everyone..

DonP152

Thanks

First, many thanks for your responses and help.

To answer a few questions.

Yes, I've had every combustion test, air mixture test and pressure test known to man done to this unit.  As mentioned I've had the Senior North American Rinnai Service Manager out 4 times along with my very competent installer / techs who worked with the Rinnai tech service multiple times.

Rinnai has replaced my original burner, but, as mentioned, because they sent a "display model", there was a broken clip holding the computer board so they re-used my old computer board.  After all of the testing that has been done and all of the adjustments made, I'm of the opinion that my original computer circuit board is the culprit, possibly causing delayed spark/ignition.  One thing I did find out was that Rinnai uses a carbon impregnated string ignition "wire" which when replaced with a Honeywell aftermarket wire did improve the ignition somewhat.

What I found interesting was that Rinnai would not allow the "field adjustment" that fixed my issue (the deflector plate) and that they've not responded to the audio file that was sent to them.

I believe, after the holidays, I will ask for a new computer board and will post my results.

I do have one further question regarding the baseboard water heat.  If, I was to deactivate my outdoor sensor and continue using my programmable thermostats as I did with my oil burner, will the efficiency of the gas fired burner drop dramatically?

Lastly, a conversion burner was not applicable in my case as my old oil burner was on it's last legs.



Many thanks again & Happy Holidays!

icesailor

Banging Heads:

Carbon based ignition wires in cars were supposed to stop electrical interference in radios. If you had a performance car, it was the first thing you replaced and went to solid wire core cables. In the days of the Muscle cars, who was listening to the radios when you were banging gears with someone else beside you, trying to go faster than you?

All the ignition wires I see are solid wire core cables. But

furnacefigher15

Hope the board does it

But if not, I wonder if you have a venting problem.



I had a customers furnace once (15 years ago) that had similar trouble. We followed all installation guidelines to a tee. In this case the application was borderline, between 2 and 3 inch flue and combustion air piping and we figured we'd be safe with 3 inch. The manufacture was of no help. (this was before combustion analyzers were common)



We eventually figured out the amount of air coming into the burners was too much, or moving too fast, and preventing normal ignition. What we ended up doing was adding restriction to the intake air, and the problem went away.



I'm not saying the problem is the same, just pointing out there is more to combustion then the unit itself. A lot of service personal have a tendency to focus on the equipment, and more or less have blinders on and not notice what the unit is connected to.

Jack

You might try this

I worked with Rinnai as their rep for many years. I no longer do so, but over the past few years since the intro of the boiler, I solved ignition issues, delayed and no fire, by changing the gas supply. Turn off the gas cock and tie in a 20 lb cylinder of known good gas at the drip leg for the test. Certainly, I cannot say it is the gas, but with a new tank set, the change has worked. At this point, after all you have gone thru, it is worth a try.

DonP152

Gas change

We've actually tried 3 different tanks of gas so far.   Initially we had a 100 gallon temporary tank, then we had my 500 gallon permanent tank and during one of the tech calls with the Rinnai rep, we used a 20 gallon drop tank.  All had different gas fills so that we could eliminate over methanoled gas.  Since May I've had 2 refills, each at about 100 gallons so I'm pretty sure we can eliminate the gas or tank as the issue.



Thanks for your input.

don_9

sensor

Hi Don.let me say we are still in the learning process with this type of equipment.

let me first explain my reasoning for jumping out the outdoor sensor.My understanding is that it will monitor the outdoor temps and will increase the btus after a certain amount of time.Example..start in low fries and will ramp up the btus after lets say 30 mintues.Now when i spoke to my rep about setting the curve on outdoor reset he was kind of vague about it and i got the feeling that he was not sure himself.So i still in search of on this issue.I was told to bypass the stat bc I really did not need it being i was in a warmer climate and its more for people of north.LOL.I was like heck people up north have no need for it bc they will be running at design temps most of the winter anyways.

Ok enough of that.I have install one on a lowmass emitters with copper baseboard with outdoor stat connected and its would not bring up the temps quicker enough.So i bypass the stat and all is well.

The second one i have high mass rads with outdoor stat connected and it does a wonderful job maintaining temps and comfort.

Bear in mind that my results just show that every house is different and their is so many variables that changes things.that why we have to always look pass the nose on one face.

I think you would be far better at this time to install the programable stat and bypass the outdoor sensor.And no your effiecency should increase being you have it held out for awhile.and you are coming out of setback.now as far as fuel comsuption that another story best left up to the pros in your area.

Hope this helps. 

icesailor

Draft:

Interesting observation of yours, FF. We sootsuckers are well versed in high draft issues. Especially if you live and work in an area where the wind can blow the rectal orifice out of a dairy cow. And that wind will blow from any direction at any time of the year.

Sealed combustion in oil seems to have been a disaster. I often wonder about why gas sealed combustion doesn't in fact, have the same problems. Oil shuts off on safety. Gas will recycle. As long as it keeps running, you never know it had a problem.

AMH112181

Setback

Your setback is too much with outdoor reset I have found 8 degrees to be too much. Your boiler runs at a lower water to save you money which is why it is taking too long to catch back up. I use the set it and forget it with outdoor reset let the boiler do what it is supposed to do. If you still want to setback your thermostat try 4 degrees and experiment with it but 8 degrees will take a while to come back up.

DonP152

Update

Update.  Feb, 2nd.

Replaced the computer board shortly after the first of the year.  No change.  Still explosive on cold fire.

After threat of legal action, Rinnai finally sent a factory fresh new boiler versus the display model last time.  It was installed yesterday.  This morning..."BOOM"  same thing.

3 burners, 4 different fuel supplies, this has to be an issue with air intake.

Interestingly enough,  this brand new factory unit wouldn't ignite at all at first and my techs had to tweak the air/fuel mix ratio to get it to ignite.

I would have to give Rinnai a failing grade for both manufacture and customer service.

As far as low heat, we're learning to live with colder than oil heat and much, much slower hot domestic water.

kcopp

I presume....

The flue pipe is the concentric Ubink pipe? How long? How many sections? It is possible there is a rolled o-ring causing cross contamination? Very odd. all those changes and still an issue... Where in the house is the boiler located? What side of the house? Do you get a lot of wind?

I agree on the set back... if the boiler has outdoor reset set back  tstats are a poor match.

don_9

It would be a shame

To blame a company for your issue when you could still have a install or distribution issue..

If it was a venting problem then it could easily be detected by watching your co action during the run cycle.If it were a fuel issue then o2 numbers and stack temps would be off.

It only does it on a cold start but does not after it warms up? Would you care to share any test numbers with us?

DonP152

Numbers

I would love to share numbers, but I don't know them, being a homeowner and not a tech.

What I can tell you is that two of my techs used two different analyzers to test and tweak and in their eyes the numbers were correct.  I do know that the factory settings for this burner were so far off that it wouldn't even ignite until they changed them.

The Rinnai Senior Service Manager also said numbers were correct the 4 times he was out here.  They also did a atmospheric (?) test and gas pressure test and both were ok.

As far as fuel, as I stated earlier, we've had 4 different fuels including a drop tank so those issues have been eliminated.

The unit is located on the north side of my basement.  Mounted on the wall with an intake/exhaust pipe that goes up approx 8" into an elbow and the out through the wall so I'm not pulling or pushing air/exhaust for more than a couple feet .

This being the second night of the brand new burner, it was decidedly quieter on startup than it was the first night.  I am going to monitor it for a few days before claiming victory or defeat (again).  Many thanks for all your input and suggestions.

kcopp

now we are getting....

somewhere.

 The north side of a house is prob the worst side to locate a boiler boiler w/ a direct/ concentric vent. The wind blowing can give you all kinds of issues.Delayed ignition just one.

DonP152

Update. 1 1/2 years of trouble

For anyone following this thread, I'd like to update.

Rinnai, finally sent a factory fresh boiler in with a guarantee that it would work or they would send "senior engineers" out from the factory to fix it.

Well, it didn't work.  Same explosion on cold ignition.  So the engineers flew in from GA.  It was actually quiet comical when they first fired it up and "kabooom".  They gave each other what could only be considered an "oh ****" look.  At this time I had the owner of my propane company, his senior tech, the owner of the wholesale house, his sales rep and two senior engineers in my basement.  They all heard it as well.   Anyway, they took out their laptops, gauges, monitors etc... and tweaked for 5 hours.  Got it to where it wasn't exploding anymore.  Put the cover back on and "kabooom".  They tried and tried and eventually after about 9 hours they had to leave.  I asked them if it was fixed and they replied "possibly", but they had 9 hours of data they could analyse!  To make a long story short, it wasn't fixed.  Keep in mind that it's now been a year that I've had this issue.  When I contacted my propane company regarding what Rinnai had told them regarding this, they told me that Rinnai had said to install someone else's boiler.  (gives you a lot of comfort and faith in Rinnai eh?)  They offered to install a Viessman for me and I agreed.  Then.... turns out the Viessman would be a $2,000 upgrade! or, I could have a Navien for n/c.  Having invested upwards of $8K by now, I was not in the frame of mind to invest another $2K for a problem, that was never fixed from day one.  I did some research into Navien and discovered that they had issues with noise, long delays in hot domestic and no hot domestic with a low flow.  I expressed these concerns to my propane house and they assured me that these concerns would not be an issue.  (One thing I did find out during my research is that Navien is recognized for having a value priced unit and pays labor....)  I am not an expert on gas fired boilers, so I had to trust in my propane house that they would not let me down.  Thus far, they had gone over and above and I was quite comfortable.  So, a Navien CH-180 was ordered, the Rinnai was removed and the Navien installed.  Turned on the gas, went to fire it up and the tech immediately shut it down, shut off the gas as there was a gas leak in the unit!  Turns out it had been dropped or hit with a forklift, cracking the housing in the venturi supply line.  So they went and fetched another one and installed it.  They now had the Navien regional manager (I believe) there and they tweaked it so it wouldn't howl (I guess this is common in Navien).  Got it working and left.

I gave it a couple of weeks and then contacted my propane house regarding it.  Turns out, all of the concerns were valid.  It's incredibly noisy, sounds like a piper cub plane revving up and down constantly.  The domestic hot water clangs, bangs and clunks every time water is called for and, worst of all, it takes almost a minute and half to get domestic hot water, 20 ft away through insulated pipes.  This happens every time with the exception of 1-2 minutes after the "plate warmer" starts.  I even sent them a video with timer showing it.  If you don't think that's a long time, try standing in your shower for 1 1/2 minutes with cold water running next time.

When I informed my propane house abut this, I got a reply from them that all burners of this nature make this kind of noise, all burners of this nature take at least a minute to get hot water and that if I had any issues, to call Navien.

So... a year and a half later, I have a Navien boiler, the KIA of the gas burner industry, I've paid for a Rinnai, the LEXUS of the gas burner industry.  I have incredibly slow hot domestic, I'm out my initial investment of $10K including first fill, I'm out approximately $5K of lost income (I'm a commissioned sales rep) from having to be home for every fix and my propane company has basically washed their hands of me.

I remember an old oil company advertisement showing how the "big gas" companies don't respond and don't care about their customers like the local oil guys do.  While I really have no complaint with my propane company and understand that they need to wash their hands of me, it greatly concerns me that this industry doesn't stand behind their product.  My propane company had to purchase 2 additional Rinnai boilers to try and fix my problem.  Rinnai and the wholesale house never gave them a dime in compensation for what everyone in my basement that day recognized and agreed was defective product.

Now I am stuck with a loud, inefficient, poorly working Navien boiler because my propane house can't or won't spend the time to fix it.

My wife, my friends, my neighbors and unfortunately now me, consider this the biggest mistake we've ever made.

JStar

Stupid question

Has anybody checked the incoming pressure of the propane?

Zman

How is it vented

How is it vented? What type of pipe is used? What does the area on the outside of the house look like?

Could you post some pictures?

Are you at high altitude?

You are a patient human, to have not "gone postal" over this.

Carl

Bob Harper

delayed ignition

This is my first glance at this thread and Jstar beat me to it. I see no mention of the inlet gas pressure. If this was even taken, was it a static pressure or with the unit firing? Are there other appliances feeding off this LP tank? Has the LP supplier inspected, tested or replaced the medium pressure regulator? Has anyone inspected or replaced the gas line? I have found delayed ignition cases where the gas line was pinched, partially filled with water, and in one case, full of gravel! A manometer can tell you pressure but it cannot tell you flow.

If the unit is installed Per Mfrs Instructions (PMI) with the spec. venting, power, controls and fuel and it still delays ignition more than 4 seconds then it is defective and must be replaced. Note that once you've had one explosive ignition, the unit may be damaged depending upon the severity of the overpressure. Seals can open up changing the dynamic of the flow of combustion products and byproducts.

If the great minds of the world cannot solve this riddle or find the smoking gun it is time for a full refund and switch to another technology. If they balk, you do have recourse both in local small claims courts and through the CPSC, who can find out of the mfr. is experiencing a similar problem with other units. I hate to involve them but sometimes it is warranted.

A delayed ignition is hazardous both to the appliance and occupants. An explosive ignition is blatantly 'dangerous' in ANSI terms so that offending appliance should be tagged out and locked out.

Steamhead

And I don't see where you mentioned

where you're located. I think someone other than the propane company needs to work with this. Tell us where you are and maybe we'll know someone close to you. 

Alan R. Mercurio_3

I agree with Steamhead

If you're going to find some one to help you straighten this out you're at the right place "HeatingHelp.com" Please tell us where are you located?

j a_2

Rinnai

I to just saw this thread and agree 100 %  with Ron...Lock that thing out and do not use it, internal damage most likely occurred...I have and will continue to install Rinnai   Never once have I had a problem caused by Rinnai...Only time I had a noise was a rumbling on start up was due to my own fault by not checking to see if the rubber gaskets were installed correctly in the venting system, one of them rolled out on me...But I did call Rinnai and the tech guy knew the answer before I finished my question..fixed in minutes...I will say I have never done one fired by propane...I really don't care for it...I hope you find your answer, be sure to locate a  plumber/tech who can handle it..there out there... I always thought delayed ignition was when it loaded up with fuel and then lit off, late....proper diagnoses is key in your situation...something is being overlooked, most likely simple...over-thinking things is common practice and costs time and money...Go to the basics  intake/venting/fuel/, do the other appliance's work OK,upstream and downstream of the supply...Ja

DonP152

I'll try to answer

I'll try to answer as many of the questions as I can.

I'm in Massachusetts, sea level elevation.

First of all, keep in mind that the Rinnai in question is now gone and I have a Navien.

The original Rinnai had the dual incoming/venting pipe that went out the top of the unit, up approx 18" and elbowed out my wall. Northside of the house in a predominantly non-windy area. We originally had a temporary 100 gal tank and it had the ignition problem, we subsequently hooked up to a 500 gal underground tank and still had the same problem and then used 2 portable tanks hooked up to the drop leg so I don't think pressure would be the issue. I have a gas stove and gas grill hooked to the same supply line, but they are after the burner supply. Had this issue before both came online as well as after. Also, please keep in mind that we had both the Senior North American Service Manager from Rinnai and their two Senior Engineers from the factory out and the only thing that fixed the issue was the non authorized field adjustment of adding a metal piece to create more turbulence (see prior post)

So, my Rinnai problem is gone as is the Rinnai. I believe it's actually been installed in the owner of the propane company's home. The propane house did mention that they had one other person with the same, but lesser issue of loud cold ignition.

My latest issue is with the Navien with the noise and the incredibly long wait time for domestic hot water. The noise, if it actually is "normal" for the unit I can deal with by soundproofing my basement. After all, it was our decision to put the unit where it is. The delay in domestic is what really concerns me the most right now. It seems like a heck of a lot of water to waste every time we need hot water.

The Navien setup is with dual pipes. 4" pvc intake and exhaust. Intake is from the west side of my house, about an 8' run, exhaust is to the north with the same 18" run. I have no firing issues with the Navien, just the noise and slow domestic.

Many thanks to all who've responded.

SWEI

slow domestic

Are your hot water pipes insulated?  An end-of-line hot water recirculation pump like this http://completewatersystems.com/product/act-e1-autocirc/ will take care of the water waste.  If you use an occupancy sensor instead of the timer you can cut the fuel waste as well.

DonP152

recirc

Pipes are all insulated.

This may be the best solution and something I can install myself with the plumbing knowledge I have.

How would an occupancy sensor work with this?



Thanks,

Paul48

You'd

have to use a sensor to power the outlet for the unit. Have you seen motion detectors turn on lights? Keep in mind, you will get a few seconds of hot water out of the cold faucet.

SWEI

occupancy sensor

Taco and Uponor (and probably others) offer pre-packaged solutions, though the Laing pump I linked to above is more efficient. 





http://www.taco-hvac.com/uploads/FileLibrary/100-49.pdf

http://www.uponor-usa.com/Header/Service/For-Professionals/Products/DMAND.aspx

j a_2

reciirc system

I am not familiar with some of the  products mentioned, however it sounds to me like they involve a cross connection..If that is the case, be very careful, a local plumber should be consulted..If its in Mass. cross connections are not allowed, last I checked...Anyone can check state approval of a product...J A

SWEI

cross connection

It's all domestic water -- is there an issue?

j a_2

Not quite sure

I just do not think you can mix hot and cold water,,could  be wrong as rules change, I will do some homework..OK?

SWEI

I'd be interested to learn

if there is a potential issue.  The only thing I can think of is that the 70-85F warm water slug that ends up in the end of the hot supply line might have the potential to harbor legionella, though it's only there for a short period.



The Autocirc has a check valve in the head, so the install requires only two standard faucet supply lines, a screwdriver, and 5-10 minutes of time.



Adding an occupancy sensor requires purchasing a relay and a couple of hours of time, unless you can find a way to make a pre-packaged lighting sensor work.  It's usually faster to install the relay and run low voltage cable to the PIR.

j a_2

Agreed

I was at my level 3 taring for Rinna,i very recently, and then marketing dept came in after that, they discussed the same type product as you mentioned..There was some discussion about exactly the concern you have....and if the product was Mass.. state approved...Often the book is ambiguous,at best..I never followed up as I have yet to come across the need to install one....Due to the 100 ft. liner rule..Have you?  That is my issue...Again,if it is a listed fixture. then its OK to use  JA

DonP152

Recirc without crossover

I have a single story, unfinished basement underneath the baths / kitchen and my hot line deadends at the end of the run due to moving my boiler from one end of the house to the other.  I'm thinking that the best solution would be to run a dedicated loop on the hot side only, (eliminating the need for a crossover under the sinks), back to the burner supply with a pump that has enough flow 1/2 gal per minute to get ole chitty, chitty bang-bang (Navien) fired up.  If I use a one time push button, we can just push the button to activate the pump, go make coffee while the Navien heats the loop and then have quicker hot water.

Am I on or off base with this idea?

Thanks,

j a_2

follow up

As promised I did a follow up and confirmed, based on the current Mass plumbing code unless you have product approval you can not create a cross connection..This is to protect your health...FYI  in Mass you must file a permit and have it inspected   JA

SWEI

crossovers

Codes are what they are, but I'm having a little trouble understanding what risk a properly check-valved end-of-line recirculating pump "crossover" presents.  How is the slug of warm water sitting at the end of the cold supply line any different than same slug of warm water which is created in the hot line as it cools down after turning off the faucet?  Why does not moving it over to the cold line present less risk?



ME, are you out there?

SWEI

should work just fine

Use the smallest recirc line you can (3/8" is great for residential if you have the tools) and be sure to insulate the recirc line and fittings well.  You need check valves both where the recirc line tees into the CW inlet, and another ahead of the CW inlet feeding the same tee.

j a_2

cross connection

If you feel that strongly about allowing cross connection i suggest you approach the state plumbing board and file for a variance   I used to take my high school plumbing class over to the meetings on a regular basis as it is held open to the public in Quincy Mass...Those are the guys to ask as they are all very well educated...I don't teach anymore due to not enough kids wanted to enter the plumbing and heating field...Until, they finish high school and open there eyes...Then its to late they just passed up on 3 years of free training in a state of the art facility offered by the public school system...Ja

SWEI

no strong feelings

Just curious about the reasoning behind the requirement.



I don't knowingly violate codes but I do like to understand why they say what they say.

DonP152

Navien Update

Navien works terrible.

Twice since Oct, 13th had error message with no heat/dhw

Noice is easily 3 times as loud as Rinnai or any other I've listened to.

DHW is still 1 minute to 1 1/2 minute to hot.