Miss firing

Showe_123

Hi I’m new to the site hopefully someone will have some advice
I have a G115 buderus external hot water heater ..main controller on front button off unit ..it was running not great but was running ..i noticed it wouldn’t fire up on the first ignition second one would fire ..it up it would continue to work from there on out ..figured it was time for a cleaning,been about a year and a half since last service..had a qualified tech so I thought I guess ...licensed etc...I was home when he did the service ..he said the box was ok he checked the stack on the back and said it didn’t need to be cleaned out mmmmm...interesting,I asked if he minded me watching love to learn new things..stayed out off his way just watched..I am a automotive tech been disabled from a bike accident, know a little about fixing things just hard to do anymore since accident..told him how it was acting etc he agreed just probably a service..he replaced the oil filter..jet..the jet tube I guess it look like to me ..it was pretty black ,he cleaned that piece and installed the jet ..scraped the end were jet comes through fins I guess you call them maybe...when he was finished with tuneup ..the unit ran worse wouldn’t run at all . He messed with the vent on the main control head ..still nothing..he proceeded to tell me he might have installed the wrong jet ...sure enough he did ..he installed the right one ,while sliding in the housing for the jet controller he noticed something in side the little control box were the circuit board is and said to me he didn’t know why that was in there and left it out ,extra part I guess mm lol ..he put it back together without that piece in there ..it fired up and kicked out still a problem..at this point he’s all swearing bla bla bla ...I said to him the piece he left out may have to be in there not trying to tell him how to do his work just seemed weird to me ..he looked at the piece and took the little cover off were the circuit board is and so we’re it was supposed to slid in ..asked him what it is called he said nothing still muttering..swearing etc..it still didn’t want to fire right away ,he messed with the vent ..and then it started to work normal..you could hear the pump come on count to 10 to 12 sec it fired up ..seems to be working ok for at least a few days ..I was down stairs in my basement that morning and noticed it intermittently firing on and off for about 5 to 6 attempts and then finally fired up ...I did some research on the part he left out ,,come to find out it’s called the cad cell eye ..the tech did tell me if it acts up again gonna need a new pump $$$$ dollars. I think the cad may be dirty not letting enough light in to detect flame then finally sees it and kicks on ..I was gonna try to check the cad eye cell and open the door to see how dirty the system is I’m sure it is pretty bad ..any advice or tips would be greatly appreciated..can’t deal with parts replacer..I can’t seem to find the cad cell eye any were on the web ..I’m sure it’s probably pretty cheap to just get one ..just in case I need it want hurt to have for a back up ..p.s I replaced the batteries in the thermostat already ..I think it’s gonna go back to a good cleaning fingers crossed ...I have no faith in this tech sadly,from what I already so sorry for the long letter just want to let you know what I’m up against...it has been working fine as far as I know but ..who knows I’m not in my basement all day to examine it all day ...when it does come on the last day or so it’s been firing up around 10 12 sec first time ..again any suggestions would be much appreciated...p.s this guy around 65 been doing this his whole life .
Thanks scott

EBEBRATT-Ed

I think we both know you need a new service company. I am a little older than your service tech and I know I am not up to speed on all the new stuff. But at least I know it.

Did he do a combustion test?

Start by sniffing around and calling Buderus and or a supply house that sells Buderus to get a recommendation on a new technician.

Also check "find a contractor" on this site and post your location. Someone may have a recommendation.

If he left the cad cell out the burner would light and then go off on safety. I know that much

Big Ed_4

What brand burner is installed on your Buderus .. Assume it's oil

Ctoilman

omg....find someone else.  Sounds like your Buderus has a Riello burner, which is fine, but that burner is quite finicky and very sensitive to settings, air volume, nozzle type, draft, etc.  Anyone who services thoroughly will have combustion test equipment....gotta find them, should be quite easy actually.

BDR529

Got any pics? Burner and boiler.

Ironman

 Don’t let that guy back in!

Anyone that would leave the cad cell out and say that it’s not needed is an idiot, not an oil burner mechanic. The cad cell, coupled with the primary control, is the essential safety for the burner.

As others have mentioned, no adjustments should be made to the burner (like changing the air settings) without using a combustion analyzer.

Showe_123

1st thank you so much to responding...yes I would agree to finding someone else ..and no he didn’t do a combustion test ..he also said these systems are so temperamental and not worth trying to replace anything in the pump etc just replace it ..if it needs to be replaced but I’m not convinced ..it did shut down when he left the cad cell eye out ..
Big Ed the system is oil ..
Winter in my area is winding down ...it’s been working I guess ..set temp at 71 it holding it at for know ..but who knows how many intermittent times it kick out ..and then starts to work again .I’m not down in the basement all day lol ..
My son said he would help me clean it out when we get a run off good days ..want to open up the box and vacuum out the system and check the cad cell eye ..
If there any test I could do I’m ok with reading a volt meter ..I have a multi meter to use ....just want to say again thank you and anyone willing to give me suggestions god bless and have a great day .

STEVEusaPA

Please don't even attempt to try to do anything yourself. This isn't an old Chevy you can putz around with in the driveway. You will do more harm than good, possible dangerous harm to life and safety.
This a sophisticated boiler, burner and controls. It needs to be cleaned, checked and tuned by a professional, someone with the skills, tools, and knowledge to make sure you have a safe operating, trouble free, efficient system in your home

Showe_123

The cad cell he left out probably fell off when he pulled the unit out to replace the jet ...probably not use to seeing them not hard wired ..the cad eye slides over a circuit board ..not wired if you know what I mean.he definitely isn’t coming back in for sure lol..
Once I do what I can do cleaning the box ..check the cad cell eye ..I’ll have someone test the combustion to set it right
I’ll send pictures when I open the door up ..thank you .
Really appreciate all the suggestions you guys are awesome.

Ironman

Cleaning the boiler block is very simple on that unit. You’ll need a long radiator brush, vacuuming is not sufficient.

As Steve said, you need a knowledgeable pro with instruments to do the burner. It’s sounds like it’s a Riello which is a great burner, but they can be a bit finicky.

Showe_123

Iron man I have the boiler brush ,and shop vac ...I do have a lot off auto mechanic knowledge..Tech 1 certified ,I know a lot about computers etc ..voltage ..those systems run high voltage..as most do ..I appreciate peoples concerns ..I’m just gonna open the door and do a cleaning..check the cad cell eye ..for cleanses..see how it goes from there for a few days ,if it works ok ..then find someone to check the combustion analyzer,if it doesn’t fix the problem I will definitely look into another license person who by the way got a 5 star rating ..
Again thanks for the info and peoples concerns .much appreciated
Scott