Hi all,
I have a golden oldie system - Netaheat Profile 50e boiler situated downstairs, F+E tank/Grundfos pump/V4073 mid position valve up in the loft and set up as a Y plan system. F+E tank level is as it should be.
I've had some problems with the boiler overheating and the overtemperature trip operating. The V4073, pump and overheat stat were replaced about a year ago, the system was flushed through with X200, several of the radiators were removed and blasted through with a pressure washer. F+E tank was drained and cleaned and then X100 was added. Things were a lot better.
Recently however I seem to be suffering from air appearing at both bleed points either side of the V4073. If left long enough the system ends up with the boiler cycling merrily (but not going to overheat) and no hot water with cold radiators.
Having had a good read of the forum, I suspected that there's more than a little sludge present so went hunting with a magnet up in the loft and found that the Myson Aerjec and much of the associated pipework is very magnet friendly
From what I've read here I think that the cold feed may be partially blocked and air is being drawn into the primary loop via the vent pipe. Oddly the air doesn't appear in the radiators so I don't think it's being drawn in via the radiator feeds.
I'm thinking that when the weather has warmed up a bit I'm going to chop out and replace the affected pipework. There seems to be a general feeling here that the best place for an Aerjec is in a scrapyard, so I'm looking to replace it with a more up to date piped arrangement.
I'd be very grateful if you heating engineering guru's could point me to a diagram or description of how the pipework should be arranged for best operation once the Aerjec is gone ? I believe that the cold feed junction point relative to the F&E overflow is critical, as is the minimum height of the overflow before it changed direction to vent to the F+E tank ? Also, would it be advisable to run the cold feed in 22mm pipe instead of the 15mm that is currently in place ?
If a photo of the layout would be helpful please let me know and I'll try to upload.
Thanks in advance
Kind Regards,
Robin
I have a golden oldie system - Netaheat Profile 50e boiler situated downstairs, F+E tank/Grundfos pump/V4073 mid position valve up in the loft and set up as a Y plan system. F+E tank level is as it should be.
I've had some problems with the boiler overheating and the overtemperature trip operating. The V4073, pump and overheat stat were replaced about a year ago, the system was flushed through with X200, several of the radiators were removed and blasted through with a pressure washer. F+E tank was drained and cleaned and then X100 was added. Things were a lot better.
Recently however I seem to be suffering from air appearing at both bleed points either side of the V4073. If left long enough the system ends up with the boiler cycling merrily (but not going to overheat) and no hot water with cold radiators.
Having had a good read of the forum, I suspected that there's more than a little sludge present so went hunting with a magnet up in the loft and found that the Myson Aerjec and much of the associated pipework is very magnet friendly
From what I've read here I think that the cold feed may be partially blocked and air is being drawn into the primary loop via the vent pipe. Oddly the air doesn't appear in the radiators so I don't think it's being drawn in via the radiator feeds.I'm thinking that when the weather has warmed up a bit I'm going to chop out and replace the affected pipework. There seems to be a general feeling here that the best place for an Aerjec is in a scrapyard, so I'm looking to replace it with a more up to date piped arrangement.
I'd be very grateful if you heating engineering guru's could point me to a diagram or description of how the pipework should be arranged for best operation once the Aerjec is gone ? I believe that the cold feed junction point relative to the F&E overflow is critical, as is the minimum height of the overflow before it changed direction to vent to the F+E tank ? Also, would it be advisable to run the cold feed in 22mm pipe instead of the 15mm that is currently in place ?
If a photo of the layout would be helpful please let me know and I'll try to upload.
Thanks in advance
Kind Regards,
Robin
