Can anyone help interpret these oil boiler servicing test results?

helpappreciated

Thankyou if you can. We're buying a house with oil heating/hot water and I know nothing about oil boilers. Please can you tell me if this looks normal or if there's anything to worry about? Also the CO level on the sheet we've been given is blank - would this have been on a separate printout that we should request (if they have it)?

Its a Grant Vortex pro 15-26
Burner Riello RDB1
Flue type CF-LLD
Burner type PJ Fuel type C2

Efficiency Nett 95.7% Gross 90.1%
Excess air 37.3%
CO2 11.25%
Nozzle size 0.65, angle 60, pattern EH
Flue gas temp 78.1 degC

Also the tank is 2000 ltr single skin unbunded plastic. Is it normal to have a single skin unbunded tank - sounds like it could be a leak liability? The owners say they don't know how old it is - do they need replacing frequently? Also there is an advisory on the sheet noting flammable material within 60cm of the tank - I think we can clear this if necessary but I need to check what it all is - if we cant clear it all is that a problem?

Thankyou!

HVACNUT

I don't believe the burner, boiler, or tank is available in the U.S.
The combustion numbers look good, however most analyzers here will have the CO reading on the printout and should be less than 50 ppm.
There should also be a seperate smoke test, and the reading should be 0.
Look into Roth fuel tanks (available in the U.K.) if that's a concern for you.

STEVEusaPA

You're in the UK?
Here's the manual for the boiler. Unfortunately that boiler is not available in the US, and I personally have never seen one to advise you further.
Plastic tanks aren't allowed here, won't pass Underwriters Laboratory, but I have seen them extensively throughout Europe.
Looking at the manual, it seems to spec an 80° angle nozzle, which may be the reason for the lower CO2 and a little too much excess air, IOW better efficiency.
CO should've been on the printout (can you post a pic of the full printout), depending on which type of analyzer they used, it could be listed as CO, COAF or CO(0).

I wish I could help you more, maybe other will chime in. It might be better if you know who serviced the boiler what their thoughts are. I don't know if you're in an area where equipment is only serviced by the manufacturer.

A condensing boiler that goes down to 51,000 btu's looks interesting (kero).

STEVEusaPA

Interesting to note, looking at the manual that a Tiger Loop must be installed outside. That's a new one for me, never heard that.

helpappreciated

Yes I'm in the UK - sorry for the confusion. Thanks so much for your help. Really appreciate that you're happy to help a complete stranger!
The CO box is blank on the service record but the sheet I've been given refers to a printout that I haven't got so I'm going to go back to the sellers and ask for it.
Good to know that some of the other figures aren't wildly off.

New England SteamWorks

If I did my math right, stack temp of 78c is 172F, and if so the test was taken before the system got up temp, which makes it sort of meaningless. Not familiar with the equipment, but here when I have a Riello I like to nudge the excess air closer to 30%.

unclejohn

See I didn't pick up on the deg.C in the post and I'm thinking that is one heck of efficient boiler or it's off.

STEVEusaPA

It is a condensing boiler, at over 90% efficient. I'd bet the stack temp is correct. If it doesn't have the right nozzle, based on the manual, putting in the right nozzle will (should) get it running at it's best.

HVACNUT

Why don't we have these oil fired options in the U.S.?
Buderus no longer imports the G125BE (both condensing and non condensing) 90+% AFUE because the cost between it, and a regular G115 was major, for a 3% efficiency gain.
It's a shame that efficiency is mandatory and accepted in Europe, and we can still install boilers with tankless coils.
I know they pay a lot more for fuel, but the technology is there.
When will we wake up?
I still need to get my hands on a Carlin EZ H2L burner.