New member - Riello RDB lockout problem

[lawnmowerman]

I have just joined the forum and I have found it to be a superb source of information. I was prompted to join to try and sort out the problems on my Camray 5 boiler. It is soon to be changed for a Grant external boiler but a friend of mine who is a registered installer has not managed to fit it yet and I guess it will have to wait until warmer weather so I do not want to spend too much on the Camray but just get it working properly for a few months.

The first problem I had was an incorrectly wired hot water stat which meant that the 2 port valve opened up and fired the boiler as soon as the power was switched on. I managed to fix that by replacing the Wickes stat with a Honeywell and rewiring the wiring centre correctly. I also changed the valve while I was at it.

The second thing I noticed was that when the boiler fired up, the lower primary pipe pipe warmed up first so I guessed that they were reversed. Last week I fitted some new rads and replaced some others so while the system was drained down I swapped the boiler tails round.
I then tried to fill the system but the pump remained dry. The primaries go up through the loft and back down to the boiler. There are a couple of automatic bleed valves in the loft above the pump but they did not seem to do much. After about four hours I had that Eureka moment and removed the auto bleed valve above the pump at the compression fitting and put I hosepipe on it. It did the trick and blew all the air up into the header tank and when water started coming out the overflow I took the hosepipe off, put the valve back on and I got heat at last on all rads. The auto valves got rid of the remaining air.

The other problem I have had ever since I moved in about 18 months ago is intermittent lockout of the burner. I searched the forum for possible causes and came up with motor, photocell, igniter, no oil, air ingress, dirty filter, frozen water in the line or control panel

I have been out overnight before a come back to a lockout and a freezing cold house and in the summer running a bath a no hot water as I had not noticed the lockout.

This morning while having my coffee and watching the news I actually caught it in the act! Both orange lights came on and this is normally followed by the motor starting and four or five seconds later there is a click from the igniter and the boiler fires up followed by steam out the flue. This time however after the lights came on there was a faint buzzing noise for about four or five seconds and then straight into lockout - red light on the control panel and red light on the burner. When I pressed the burner reset it fired up immediately.

Based on what I have learned from other posts on this forum I have narrowed it down to the motor or capacitor. Being as the capacitor is cheaper I have ordered one today and hopefully will arrive tomorrow. One question I have is that I was told that the new version of the capacitor is 4.5 mF and replaces the old one which was 4 mF. I have a 4 mF fitted. Was this changed by Riello to cure this very problem?

Am I on the right track with this fault? I hope it is not the motor as I am not looking forward to dimantling the burner and I have read some horror stories on here about getting the fan impeller off the shaft and having to cut it off and fitting a new one.

Thanks

Jim

 

[Dotty]

Hiya. You're on the right track there. It sounds very much like the capacitor's shot. Don't worry about the slight increase in mF, Riello try to implement a one size fits all policy, some domestic parts work very well on commercial burners for example. If, however, the capacitor doesn't cure the problem you may have half a mouse stuck in the fan housing. And if that little lovely isn't there then you'd be looking at a new oil pump I'm afraid.

BUT!

If you are indeed replacing your boiler soon with a Grant then you may be able to strike a deal with your local supplier and get him to split the burner/boiler for you and fit the new burner on your existing boiler until you replace it.

 

[lawnmowerman]

Hiya. You're on the right track there. It sounds very much like the capacitor's shot. Don't worry about the slight increase in mF, Riello try to implement a one size fits all policy, some domestic parts work very well on commercial burners for example. If, however, the capacitor doesn't cure the problem you may have half a mouse stuck in the fan housing. And if that little lovely isn't there then you'd be looking at a new oil pump I'm afraid.

BUT!

If you are indeed replacing your boiler soon with a Grant then you may be able to strike a deal with your local supplier and get him to split the burner/boiler for you and fit the new burner on your existing boiler until you replace it.

Thanks Croppie. Brilliant idea - I actually have a Grant 26/36 sitting in the garage ready to be installed - is it the same burner?
If the capacitor does not cure the problem then do you think it is a sticky oil pump rather than motor brushes or windings?

Jim

 

[lawnmowerman]

The capacitor arrived yesterday morning so I fitted it straight away. Apparently the capacitor was changed from 4 to 4.5 mF by Riello in a "one size fits all" strategy as it is used on other burners.
Fingers crossed it has solved the problem although it has only been a day. I will update results in this thread in a week or so as it may help others with the same problem.

Jim

 

[lawnmowerman]

Solved - touch wood!
The new capacitor has only been in for a couple of weeks but the boiler has not locked out once where it was doing it every day or two before. So nice to get out of bed to a warm room instead of rushing to the conservatory and hitting the reset button and freezing for half an hour until it warms up.
Thanks to croppie and others who have posted threads with similar problems which narrowed it down to a capacitor problem - a cheap fix and as easy as changing a light bulb!

Jim