Ravenheat RSF84ET Combi Boiler

[kevski]

My 14 month old Raveheat RSF84ET Combi Boiler will not start up when set to either Domestic Hot water or Central Heating. The pump, fan and pilot light do nothing but there is power getting to the Digital Timer but not to the pump. The fault finding in the Installation Guide indicates that the problem is likely to be the printed circuit board or the digital timer, I've replaced both but still no joy. Has anybody any ideas on what else could be causing the problem.
Thanks
Kevski

 

[Agile]

I cannot help think that it would have been cheaper to call a professional!

Perhaps its relevant that you did not call your CORGI registered installer first?

With that boiler problem I would expect the pump to be seized because the system was not power flushed.

Tony Glazier

 

[Slugbabydotcom]

I have great empathy for cold people. Thats why I post here. I do my best to help even though I shouldn't encourage DIY work in this specialised territory. I do help where I feel that the person I am helping is capable of doing the work safely. I have to draw a line in this case as you have blindly threw money on parts like that without first investing at least 99p on a mains tester screwdriver or better still a fiver on a cheap multimeter.

 

[Softus]

I have great empathy for cold people. Thats why I post here. I do my best to help even though I shouldn't encourage DIY work in this specialised territory. I do help where I feel that the person I am helping is capable of doing the work safely.

Astonishing! In what way has the poster indicated that he isn't capable?

I have to draw a line in this case as you have blindly threw money on parts like that...

No he didn't - he says that he followed the fault-finding section.

...without first investing at least 99p on a mains tester screwdriver or better still a fiver on a cheap multimeter.

And where does it say that he didn't invest that money?

Has someone got your testacles in a vice while you're posting?

 

[kevplumb]

check the o/h stat

 

[kevski]

Slugbabydotcom:- I didn't replace the PCB and Digital Timer lightly, I haven't got the money to spare, I spoke to a number of people and also tried Ravenheat themselves and everyone I spoke to thought it was most likely the PCB. I'm not an expert but someone who can do a lot of DIY jobs myself and only took this job on because I thought it was likely to be the PCB and it would be cheaper to do the job myself. This looks as though this wasn't the best option to take but it's always easier in hindsight after the event.

Softus:- Thanks for your comments/support.

Thanks everyone else for there help, I've still to try out the suggestions.

Kevski

 

[fitz1]

does that model have a control board aswell as the main pcb ?

 

[kevski]

In the installation guide it refers to the Control Board which is the PCB I replaced and it's also got an ignition board.

 

[Slugbabydotcom]

And where does it say that he didn't invest that money?

Before renewing the timeclock it would have been wise to check whether or not it is switching. If the pump wasn't running it would also have been a good idea to see if there was 240v across the terminals or at the board. If the pump had its voltage after the fuses or as I suspect F2 had been checked then the PCB would not need changing.
OK so you're feeling cold but capable so here goes.
Check out your main switch. With your new multimeter in hand and set for CH check for 240 at L1 and N2 on the PCB if it is there but not at L3 and N4 [The block next to F1 in case you can't find it] then your Main switch or the wiring to it is the problem.
Next check out your low water pressure switch. With the power off there should be continuity between the terminals where the black wire and the blue wire go in.
I am assuming of course that you have checked the reset button and there is enough pressure in the system.

Has someone got your testacles in a vice while you're posting?

No I just needed a shag but I'm alright now

 

[Paul Barker]

Yes,

I'm not conversant with any Ravenheats, fortunately nobody seems to have fitted them in Scarborough despite the fact they are up the road.

When you say you followed the fault chart did you comprehend the importance of each step and check it acurately?

If the boiler has a low pressure sensor, and also an overheat sensor, then as posted above these two items are a very important step for you. The fact that the fan isn't coming on, for most boilers implies a different problem to a stuck pump, because the sequence pcb's go through on most boilers before allowing ignition is ; check aps functions properly, then check fan functions properly using proved aps, then check pump runs properly via flow sensing, then commence ignition sequency.

The low level sensor and OH stat interrupt right at the start so non of these checks are made.

You check for continuity across certain pins with an ohm meter with boiler off, or you check for voltage, both sides of device, boiler on. Trace where you fisrt lose your voltage, you might even find your self back at the fuse.

 

[Agile]

Which boiler do you know Paul which starts the fan before the pump is started?

Tony

 

[Paul Barker]

Sorry have I got that wrong Tony? I thought the sequence was as above.

Sure it was on the Baxi course, do their boilers work against the grain?