Buderus Starting problems

R Mannino

Fuel Pressure

So you are only tweaking the CO2 with the fuel pressure, changing it say, 10 psi or so either way?

If so your just tweaking the flame characteristics with fuel pressure?

RobK

back to square one

A Buderus boiler has a quick recovery time. You didn't say if the on off sequences are when the boiler is firing or not. If the burner is going on and off and not firing you have a control or electrical problem.Could be the low water cut off, for example.If the burner is firing then the boiler is just doing its job.Maybe oversized for the heating load.

Tony12

Buderus hard start

I have the same Buderus boiler with a riello F3 burner.

I hates to start when the chamber is cold it rumble and the flame goes out and then retries. Buderus specks are 145psi turbulator  0 and .50 80° B

Is this Buderus's fix for this problem changing pressure to 160psi and using a 60° or 70°B nozzle.



Tony12

billtwocase

problem with this unit

has been field set up procedure. I must echo boosting pump pressure, and breech/overfire draft as generally causing the recycling problem. Alot of guys have switched to NX on these 

Tommyt

Buderus Lockout - hard start - rumble and solution

I am a homeowner and had a Buderus G115/3WS installed in October of 2009.  It worked great starting flawlessly all heating season.  In September of this year, it began hard-starting, rumbling for over 2 minutes each time on a cold start.  I contacted my installer and this is the sequence we followed:



 1.  Cleaned furnace, checked all readings and smoke (they were fine) then replaced nozzle with new 0.6 x 60B @ 145psi (same as delivered).  Problem persisted.  Decided to get different nozzle.



 2.   While waiting for new nozzle, I figured problem was temperature related wanted to see if warming burner would have an effect.  I removed the cover and put a heat gun on the burner for 30 seconds.  It would start flawlessly every time, no rumble when this was done, but return to the rumble without added heat.



 3.  Installer’s father had same problem and solved by downsizing and running higher pressure.  Installed a 0.5 x 80B nozzle and ran pressure to 175psi.  Starting was instant, but sound was a little different.  All seemed OK, but a few days later had a Lock-out on a cold night.  Multiple attempts at hitting reset did not work.  Finally, I again used heat gun to raise temperature and ignition was instant.



 4. As a stopgap measure, I placed a 7W nightlight inside the burner cover at the bottom. The next few days all worked fine.



 5.  Installer returned and installed a 0.5 x 60W nozzle @175psi and checked readings again.  This has been in the burner for 2 weeks and despite colder weather, starts have been instant with no added heat.



So:  It seems that the hard starting is temperature related. The solution that worked was to change to downsize, raise pressure and change to a W pattern nozzle.  As an

emergency stopgap, one can warm the burner slightly or even put a small heat

source (light bulb) under it.

J_W_P

Called riello about this

I have been having the same problem with a Buderus boiler as well as a Kerr furnace.  I called Riello and they call it "flashing" and believe it is due to a change in the sulphur content in the oil.  Each time I call,  Riello tells me to up the pump pressure from 150 to 175 psi.  On the Kerr furnace it was reccomended that I drop nozzle size and bump pump pressure to 200 psi with a hollow spray pattern.  I did that over a week ago and all seems ok.



Jim

Big Ed_4

Adjustments

I was directed to do the same to help silence the combustion noise Riello / Buderus 115 , you also need to drop the nozzle size to near equal the input of combustion .. I am still on the old side of the fence of using hollows in burners other then a Shell Head ... I do like the Delavan "W" in a Riello , A good in between choice with longer lasting and softer combustion ..

SimonMA

Same Problem

I have the same EXACT problem with my Buderus + Riello burner. The repair guy has come out 4 or 5 times so far to fix the problem... but nothing has worked. Each time he replaces the stem and it works great for about 2 or 3 weeks, then sure enough the starts get harder and harder after being down for a while until it starts cycling off and on until it gets warmed up.

Did you fix the problem? If not, will you PLEASE let me know when you do?