Grant air adjustment

[Geyser]

I normally fit Worcester oil but I thought id give Grant a go.
I've installed a Vortex 21/26 (RDB2)and setting it up I cant get CO2 above 10.
Oil pressure set 8.5. Nozzle and blast tube ok and air reduced as far as possible but still getting 10%co2. 50%ex air.
All I can think of is the air damper, there isnt one fitted and the manual just says fixed.
Any ideas?

 

[Best]

Did the C02 and other readings vary when you were trying to adjust the air?
The air setting that you adjust is simply a bolt that slides a plastic door and this part can sometimes fail. If you remove the snorkel hose (if it is a balanced flue) and take a look into the opening to check if the door moves when air bolt is turned. Take the bolts out of the plastic snorkel spigot and lift it off if you need to get a clear look.

 

[Geyser]

Hi Best.
Ye I stripped it all apart to check operation and it was opening and closing fine.
The readings where heading the right way until the air bottoms out and cant close anymore. I've not come across this before, I think it needs a air restriction disk fitting. Im going to call Grant tomorrow and check.
Its not right and a bit disappointing on one of the first Grants ive done.

 

[Best]

I never have had any problem with them. Does sound like too much air getting through the burner, as you say. Were you reducing the output on the boiler? (Lower than factory set)
I could check any MIs I have.

 

[Best]

Nozzle could be faulty I suppose, even though brand new burner.
I hope the kerosine supply is clean and free of water.
I would test the burner by temporarily removing snorkel hose, to rule it out and if burner still not any different, then fit a brand new identical nozzle and see if that works.
Check oil quality and also that your oil gauge is not faulty, although unlikely to be far wrong.

 

[Steve ski]

Re stricter Disk may be set in wrong position, I had a problem today with a grant ez fit 200 flue to boiler connection the m8 bolt provided was for the smaller version of the ez fit 150mm from the domehead nut to it's end needed to be 180mm, last thing I needed grant couldnt guarantee next morning delivery so bought some m8 threaded bar put dome head nut on and cut to correct size, Bloody annoying and time consuming, Good luck with it mate!

 

[Best]

Re stricter Disk may be set in wrong position, I had a problem today with a grant ez fit 200 flue to boiler connection the m8 bolt provided was for the smaller version of the ez fit 150mm from the domehead nut to it's end needed to be 180mm, last thing I needed grant couldnt guarantee next morning delivery so bought some m8 threaded bar put dome head nut on and cut to correct size, Bloody annoying and time consuming, Good luck with it mate!

That bolt is stainless steel isn't it? Would rust otherwise

 

[Best]

Geyser, - how did you get on with the problem? What did Grant say?

 

[Geyser]

Geyser, - how did you get on with the problem? What did Grant say?

Ive not called Grant yet. Im going back tomorrow so i'll have another look at it and call them from site if needed. Good idea about the nozzle it could be out, ill stick a new one in and see.
I checked oil tank for water, new filter, blew out pipe and ran oil till clear. Got burner on middle factory setting.

 

[Best]

Ive not called Grant yet. Im going back tomorrow so i'll have another look at it and call them from site if needed. Good idea about the nozzle it could be out, ill stick a new one in and see.
I checked oil tank for water, new filter, blew out pipe and ran oil till clear. Got burner on middle factory setting.

Coincidently, I had to look at a boiler on Monday I had previously serviced a while back. I would have replaced the nozzle in the service. The low level flue was, according to the customer, giving out a strong smell when boiler was running and also his radiators and hot cylinder were not really heating up well.
Burner appeared fine, oil pump pressure perfect, nozzle lovely and clean.
Readings were much the same as you had and needed air nearly closed off to get anywhere near acceptable readings. I replaced the nozzle and that sorted it.

 

[Geyser]

Ive been back and it was the nozzle. Adjusted air and got the right settings. Ill never trust a new nozzle again!

 

[Best]

Ive been back and it was the nozzle. Adjusted air and got the right settings. Ill never trust a new nozzle again!

I thought it was nozzle. That's good to hear back what it was. If the nozzle was handled, or a tiny bit of dirt or water inside it could do that.
You would assume the burners are final test fired, but probably not fully tested.
I have had new nozzles I installed on services being totally faulty, but only rarely and never on new boilers/burners.

 

[WHPES]

quick check if you come across this again, pull off the air intake hose and put a bit of card part way across the inlet, move this further over to restrict the air intake to simulate a choke flap

 

[freeoil]

quick check if you come across this again, pull off the air intake hose and put a bit of card part way across the inlet, move this further over to restrict the air intake to simulate a choke flap

Thick wall 28mm pipe insulation is a perfect fit in the snorkel.
This has got me out of trouble after finding no secondary air damper disc when altering
boiler output.Works a treats on the RDB.
Anybody got a source for the air damper discs?Not easy to come by.

 

[johnf]

I have had this a few times recently where the wrong nozzle is in the wrong box eg. 0.7580EH on the box and the actual nozzle is 0.6580EH for instance. This has only recently started to happen and we have known it on at least 4 nozzles in the last 6 months

 

[Best]

I have had this a few times recently where the wrong nozzle is in the wrong box eg. 0.7580EH on the box and the actual nozzle is 0.6580EH for instance. This has only recently started to happen and we have known it on at least 4 nozzles in the last 6 months

I check each nozzle is correct size just as I am about to fit it, for that reason.
But if I were you I wouldn't be happy to continue buying them from your supplier of they are allowing nozzle containers to be opened. They really shouldn't be handled

 

[Best]

I have had this a few times recently where the wrong nozzle is in the wrong box eg. 0.7580EH on the box and the actual nozzle is 0.6580EH for instance. This has only recently started to happen and we have known it on at least 4 nozzles in the last 6 months

I check each nozzle is correct size just as I am about to fit it, for that reason.
But if I were you I wouldn't be happy to continue buying them from your supplier of they are allowing nozzle containers to be opened. They really shouldn't be handled