Hi all,
I've got a problem(s?) with a Powermax 155x Open Vent that I'm in the process of working through. I have enlisted the help of a central heating installer on this, but he's not that familiar with the Powermax boilers (as so many seem not to be), so we're both kinda learning a bit here! If possible, then I'd like some advice / guidance from some of you experts that we're on the right line please!....
PROBLEM: I turned the boiler on Monday night and after working for maybe 30 mins, it then started making a buzzing sound like a quick-switching relay - It did this on and off for about 10 mins, following which silence from the relay, never to be heard again. The boiler still ran and heated, only now after a short period some very deep rumblings started up from inside it, so I turned it off. Having tried again maybe an hour later I got the same issue - deep rumblings after a while, so I turned it off. I tried once more on Tuesday night, and this time the burner light came on, but then after maybe 10s went out and stayed off. Fan still runs, display is present etc etc - only problem seems to be rumbles and burner either cutting out or not coming on in the first place.
WHAT WE'VE DISCOVERED SO FAR: The cut out / trip-switch top left on the unit (high temp cut-out?) had triggered, so we reset that, however, still rumblings during operation. Next thought was that the boiler was low on water, so we checked that both the vent tank water feed in to the boiler was clear (broke in to the line and it's spotless), and also checked the air vent to the vent tank was clear (blew though it from boiler end - again fine). After a bit of google-ing I found a comment that you must blow DOWN the vent line INTO the boiler to clear some sort of air lock which then allows the boiler to re-fill from the vent tank. We did this (several times) and sure enough, the boiler refilled somewhat - (a funny quirk?!). However, upon firing up the boiler, it started rumbling again!
Now, since then we've done a fair bit of fault checking, and fault finding and satisfied ourselves that everything has power where everything should, and that both pumps operate etc etc. However all this has now prompted another theory... A dodgy pump relay on the tank circulation pump??
I understand that one of the 2 pumps is simply there to circulate water within the store cylinder itself to prevent hot-spots... so our current theory is that the relay that powers this pump is not always operating when it should, thus causing the re-circ pump to not operate, thus causing hot-spots and local boiling in the cylinder (the rumbles), followed by the thermal cut-out operation as the top of the tank overheats.
Does this sound like a fair suggestion??!
Whilst I'm getting more convinced this could be the case (plus it ties in with the buzzing relay noise in the first place), we've had that many failed-theories with this boiler that I was looking to pick some brains on here and see if anyone had any experience of such problems??
Can anyone provide suggestions as to what may be up, what else we could check, prior to starting to spend money on spares?
My one other question is that I have seen a couple of threads suggesting the need to blow down the vent line to clear it and allow filling with water again in the event of rumbles / over heats. Is this a rare occurence with these boilers, or are they actually incapable of refilling if water levels get low? Hence is it something I need to monitor? Tank head is probably about 1-1.2m to the top of the store cylinder.
All help appreciated - thanks!!
As a final comment, I'll say that I do actually like the boiler when it's working and that this in the only problem I've ever had with it touch-wood - there's an awful lot of comments around with people saying how bad they are, but I'll stick-up for it (for now at least!). Cheers all.
I've got a problem(s?) with a Powermax 155x Open Vent that I'm in the process of working through. I have enlisted the help of a central heating installer on this, but he's not that familiar with the Powermax boilers (as so many seem not to be), so we're both kinda learning a bit here! If possible, then I'd like some advice / guidance from some of you experts that we're on the right line please!....
PROBLEM: I turned the boiler on Monday night and after working for maybe 30 mins, it then started making a buzzing sound like a quick-switching relay - It did this on and off for about 10 mins, following which silence from the relay, never to be heard again. The boiler still ran and heated, only now after a short period some very deep rumblings started up from inside it, so I turned it off. Having tried again maybe an hour later I got the same issue - deep rumblings after a while, so I turned it off. I tried once more on Tuesday night, and this time the burner light came on, but then after maybe 10s went out and stayed off. Fan still runs, display is present etc etc - only problem seems to be rumbles and burner either cutting out or not coming on in the first place.
WHAT WE'VE DISCOVERED SO FAR: The cut out / trip-switch top left on the unit (high temp cut-out?) had triggered, so we reset that, however, still rumblings during operation. Next thought was that the boiler was low on water, so we checked that both the vent tank water feed in to the boiler was clear (broke in to the line and it's spotless), and also checked the air vent to the vent tank was clear (blew though it from boiler end - again fine). After a bit of google-ing I found a comment that you must blow DOWN the vent line INTO the boiler to clear some sort of air lock which then allows the boiler to re-fill from the vent tank. We did this (several times) and sure enough, the boiler refilled somewhat - (a funny quirk?!). However, upon firing up the boiler, it started rumbling again!
Now, since then we've done a fair bit of fault checking, and fault finding and satisfied ourselves that everything has power where everything should, and that both pumps operate etc etc. However all this has now prompted another theory...
A dodgy pump relay on the tank circulation pump?? I understand that one of the 2 pumps is simply there to circulate water within the store cylinder itself to prevent hot-spots... so our current theory is that the relay that powers this pump is not always operating when it should, thus causing the re-circ pump to not operate, thus causing hot-spots and local boiling in the cylinder (the rumbles), followed by the thermal cut-out operation as the top of the tank overheats.
Does this sound like a fair suggestion??!
Whilst I'm getting more convinced this could be the case (plus it ties in with the buzzing relay noise in the first place), we've had that many failed-theories with this boiler that I was looking to pick some brains on here and see if anyone had any experience of such problems??
Can anyone provide suggestions as to what may be up, what else we could check, prior to starting to spend money on spares?
My one other question is that I have seen a couple of threads suggesting the need to blow down the vent line to clear it and allow filling with water again in the event of rumbles / over heats. Is this a rare occurence with these boilers, or are they actually incapable of refilling if water levels get low? Hence is it something I need to monitor? Tank head is probably about 1-1.2m to the top of the store cylinder.
All help appreciated - thanks!!
As a final comment, I'll say that I do actually like the boiler when it's working and that this in the only problem I've ever had with it touch-wood - there's an awful lot of comments around with people saying how bad they are, but I'll stick-up for it (for now at least!). Cheers all.
