Potterton Suprima 50HE combustion readings

[Clear Plumbing]

I serviced a Potterton Suprima 50HE today, full clean of burner etc, put back together, burner pressure correct at 9mb, gas rate correct at 15kw, analyser readings way out though, no suggestion in mfi of correct ratio etc, anyone had this before. I was once told by Vaillant that some of their older condensing boilers didn't need to combustion readings run and if you did, the readings would be sky high, is that the case with Suprima HE's as well?

 

[Aquarius]

Hello clearplumbing,

This should be asked in the private forum. However did you leave it long enough to not saturate your FGA? Have you checked your FGA?

 

[ShaunCorbs]

After a full clean I would run the boiler for 15 mins before putting the fga in

 

[EvilDrPorkChop]

I'd expect <100ppm too. My 18kw Ultimate runs at about 40/50ppm.

Gas Rate and Burner pressures probably need checking.

 

[Aquarius]

Just re-read post, this is a heat only boiler, don’t think there’s a need to fga, mine’s the same boiler, seem to remember calling Baxi technical and they mentioned results won’t be same as a combi.

 

[EvilDrPorkChop]

Need to FGA all boilers....
Ratio to be below 0.004

 

[Aquarius]

Need to FGA all boilers..
Ratio to be below 0.004

Even old boilers? What’s your take on this: (photo) 1st two sentences.

 

[EvilDrPorkChop]

Yeah even old ones. You couldn’t leave an older boiler at let’s say 500ppm.
If they’re burner in excess of 200ppm there’s something wrong anyway, most of the older appliances are usually under 100ppm when they’re burning correctly.

 

[Aquarius]

I must say it’s a new one on me, we’ve been told, flame picture, burner pressure and gas rate. Yes I do hold relevant quali’s before you ask, just don’t remember everything.

How would a bbu get analysed? Or a 3rd storey boiler with no sampling point?