Oil burner output query

D.flynn · 27-10-2023 2:49pm #1

Hi All,

A little background, I have had some issues troubleshooting an ecoflam max-1 tc oil burner for my sister. I wont get into the issue's with it yet, but as a solution, I have purchased a replacement burner to install thus giving me time to repair the original and then have it as a spare.

The original unit was a 16-21kW unit

I ordered a 15-21kW unit, but was contacted by the supplier (not ecoflam) stating that they didn't have it in stock, and that they could send a 12-16kW unit.

Physically it is the same size unit with all the same components.

I just want to verify what the supplier said (and what I'm thinking also), is it just a case of changing the nozzle and adjusting the pump pressure to match the nozzle in order to increase the output?

original boiler had following specs:

18.7kW 63,750BTU 0.50/80° EH 10bar pump pressure

new burner has a nozzle as follows:

0.4 80°EH 1.2kg/h EH3

Thanks in advance

jimf · 27-10-2023 10:28pm

do you have a flugas analyser to make sure everything is running safely when finished

Lenar3556 · 28-10-2023 9:35am

https://www.boards.ie/discussion/2058319892/oil-burner-output-query

You are on the right track, but;

“18.7kW 63,750BTU 0.50/80° EH 10bar pump pressure”

18.7KW will be the nett boiler output, factoring in a boiler efficiency of about 85%. A 0.50/80° EH running at 10bar on kerosene actually has the burner putting out about almost 22KW.

So your existing burner is maxed out, and if you but in another with a maximum output of 16KW, you will effectively be reducing your Applicance output by 27%. 16KW vs the 22KW that hers is currently running at.

Wearb · 28-10-2023 12:28pm

I have to agree with both Jimf and Lenar.

Jim's safety issue needs to be understood. Co is easily produced with a boiler and has often been deadly.

Lenar's comments are more to do with efficiency and boiler longevity. Under firing a boiler is very inefficient and can quickly lead to rotting out the heat exchanger.

D.flynn · 30-10-2023 1:06pm

Thanks all for the comments.

I will have the burner checked afterwards using an analyser, it's just about getting everything ready beforehand and making sure I'm OK with this.

What I'm trying to understand is, if my new burner has:

1. an identical motor (thus running at the same speed as the previous burner)

2. Identical pump

3. Identical pipework(oil line connecting pump to nozzle) and nozzle holder

In fact, all things Identical except nozzle an pressure, will changing nozzle and pressure then give me a 15-21kw unit? Even though it came as a 12-16kw unit

Wearb · 30-10-2023 2:39pm

No. If that were the case, the same settings on "identical" boilers would give the same results on an Analyser, which doesn't happen.

There are tolerances in nozzles, motors, capacitors, fans etc. They all add up to random differences in each set-up.

jimf · 30-10-2023 3:59pm

even the combustion head on the burner may be different

Lenar3556 · 30-10-2023 11:27pm

https://www.boards.ie/discussion/comment/121301373#Comment_121301373

If the manufacturer is saying the burner is designed for operation at 12-16KW I would take that at face value.

I am not particularly familiar with that burner, but based on some of the others, the air box assembly may be different/too small. So if you tried to fire it at 21KW you may not be able to get enough air into it.

You could try Ecoflam in UK (Part of Ariston). They might be able to help.

Is it installed in a Stanley cooker?

D.flynn · 31-10-2023 8:24am

Hi All,

A big thanks for all the great responses, I really appreciate it. Just a couple of points before I proceed

The boiler the original burner was installed was a Grant Vortex Wall Hung indoor 55-70
Any work I do would always be followed up with a test using a flue gas analyzer and a competent person.
On a side note, (which I think is a good idea for all indoor burners) we plan to integrate a mains-powered CO alarm in the utility room with the boiler (integrated with the mains-powered smoke alarms in the house). if activated, this will electrically isolate the boiler thus stopping the generation of fumes. this will be a latching relay so it will physically require a reset in order to start up again.

now for my queries...Just to clarify, I'm not doubting ye and value your knowledge, but My queries below are more about gaining that knowledge from ye and not from disagreeing with ye or seeking an argument. 😅

surely those tolerances wouldn't matter too much, if at all given that (correct me if I'm wrong) Output is determined by oil flow rate and air intake. The oil flow rate is determined by the nozzle and pump pressure, so once properly commissioned, we could be certain of an output +/- a few hundred watts?! taking into account that we would never know the actual tolerance of the nozzle we install.

In the below image (taken from the max 1 manual), it shows various outputs achieved by various configurations of the nozzle, air damper and firing head position (I realise now that I hadn't taken this into account in my previous posts)

The same manual shows all parts the same ( no different part numbers based on specified output)

Again, thanks for communicating with me on this, my goal now is about challenging what I previously thought was correct, as well as documenting it here for anyone else who may be interested

Thanks again

jimf · 31-10-2023 3:55pm

why not ring grant technical for their advice

Wearb · 31-10-2023 4:07pm

The only thing else that I'll say on this is that a co alarm is a last line of defence and shouldn't be used to monitor a bad setup.

I would never replace a like for like burner without doing a Analyser test. As a matter of fact I don't do even the slightest alteration or repair with finishing with a combustion and combustion gas leak test.

D.flynn · 07-11-2023 7:51am

@wearb, absolutely agree that the CO alarm is to be a backup only and that nothing should replace suitably commissioning and FGA by a competent person.

Now for the update. Mainly to validate all your points above, but also for anyone reading this post in the future)

After a thorough cleanout of the Boiler and installation of the new burner, everything was fine for an hour, than the exhaust fumes began to blacken.

Decided to shut it down and wait for OFTEC engineer to commission and verify the unit (this was always the plan)

Oftec engineer spent ages on it (after a second thorough cleanout as it was sooted up again), but couldn't get the new unit to burn correctly. He reckons that it wasn't providing adequate airflow to push the fumes out of the chamber into the flue and out of the house(for reference, the flue is only a ~1m run horizontally from where it exits the boiler to where it exits the house). @Lenar3556, you did mention the the airbox as a possible issue, even thoughthere was no discernible difference.

Oftec engineer serviced and reinstalled the old one (which had an incorrect nozzle from the last service tech(not me) and possibly kicked off this whole thing)

Thanks everyone for the responses and education

Oil burner output query

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