Basic duo tec 24he

[giarc00007]

Just installed above boiler with vertical flue. Getting explosive ignition when first ignites (not excessive but noticeable) but all checks spot on 19 mbar working pressure. Analyser readings fine. I know these are prone to probes. But this is new install.

 

[RoryD]

I would do all the basics - which you seem to have done, Inlet pressure, gas rate -air gas ratio?

 

[jtsplumbing]

We are expected to do more & more tests on new boilers now, think the next step is they will come in kit form, and we will have to assemble them on site,

 

[giarc00007]

just an update guys.baxi came out to check boiler. said the ignition is fine and within tolerance for a vertical flue. he said because of vertical run length you would expect to get slight explosive ignition. i wasnt to impressed but what can you do if they say its fine:32:

 

[Ermintrude]

Ask them why flue length changes physics and means that it's acceptable to have explosive ignition that will ruin boiler insulation pads. ?

 

[IDCHAPPY]

Must say, that's a new one on me :s

 

[AWheating]

Most baxi boilers I have fitted have had slow/poor ignition and give a smell of gas outside when firing up. Seems the way they am.

 

[giarc00007]

Ask them why flue length changes physics and means that it's acceptable to have explosive ignition that will ruin boiler insulation pads. ?

i did ask engineer he just said the longer the flue length the more likely explosive ignition. to be honest he didnt seem interested i did phone baxi and complain today they are calling me back tomorrow.

 

[dmheat]

Ask them why flue length changes physics and means that it's acceptable to have explosive ignition that will ruin boiler insulation pads. ?

It doesn't change physics, it is physics. The fan ignition speed on a duotec is set in stone, and cannot be increased. A long vertical flue has a greater resistance, both in supplying the air for combustion and expelling resultant flue gases. This will have an effect on the ignition.

Its why a lot of boilers allow you to adjust this parameter now. Increasing fan ignition speed compensates for the increased resistance of a long flue, and will prevent the ignition leaning on the heavy side.

Sometimes Remehas sound like a shotgun when fitted to a vertical flue and not adjusted,they can sound intimidating, but winding up the fan ign speed sorts it.

It doesn't make it right, or ok, but it's the explanation none the less!

 

[dmheat]

Out of curiosity, how long is the flue and how many bends (and of which angle)?

 

[giarc00007]

Out of curiosity, how long is the flue and how many bends (and of which angle)?

the flue length is 2.5m with 2 45's.

 

[dmheat]

the flue length is 2.5m with 2 45's.

Hmmmm...that's really not that long. Although what I said still stands true, I wouldn't expect it on a flue that short and something sounds amiss. Get them back out. If they play up, get the sales reps number for the area and call him up, tell him you've got X amount of boilers to fit in the next month and you were trying Baxi out as a future manufacturer of preference. Inform them politely they are going to miss out on £xxxx's in sales if they don't sort it and to expect a small claim on their hands to cover the boilers cost,your costs,customers compensation,and cost of a replacement boiler as a boiler with explosive ignition (by definition) is NOT fit for purpose. Sale of goods act should cover it nicely!

 

[giarc00007]

thanks for your input dmheat. i will do that. they were supposed to phone me today but never did. i wont let it go. thanks all.

 

[dmheat]

Let us know how you get on bud

 

[Taffman]

If its new, make sure your work is spot on and get Heat team out!!