Help! Boiler fault - no water flow or reverse flow

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Hi all

I have a Baxi Solo 18 HE boiler (heat only) with a gravity fed system

About a week ago I drained down and moved some radiator pipes in the bathroom ready for a new towel radiator. I installed the valves onto the new pipes, shut them off and then refilled the system.

The system worked for about a week but this evening the boiler is giving an error - 1 solid red light and 2 flashing green which according to the front of the case is "no water flow or reverse flow".

I have tried bleeding everything i've found including the pump to no avail. Water not air comes out of everywhere!

I can hear the pump running so that seems to be OK

Both tanks in the loft are full of water

Any ideas of what I should check next?

Thanks in advance
Ben
 
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If your certain the systems filling and the pumps ok, it's probably the flow switch which means giving your local RGI a call if it keeps faulting (I guess you've tried resetting)
 
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Is there a better way to check the pump than just feeling/listening to it?

It's a Salus pump (was changed approx 1 year ago) and it has a display on the back that's reading "24W" when its making a spinning sound

I tried removing the "plug" piece on it and water comes absolutely shooting out the side!

I've tried to reset the boiler too as mentioned above
 

CBW

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If you undo the bleed screw on the pump (if there is one) and check there, you should get a trickle of water so have a rag handy.
 
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Is there a better way to check the pump than just feeling/listening to it?

It's a Salus pump (was changed approx 1 year ago) and it has a display on the back that's reading "24W" when its making a spinning sound

I tried removing the "plug" piece on it and water comes absolutely shooting out the side!

I've tried to reset the boiler too as mentioned above
Is the " plug piece" the round ,silver disc with a slot ?
 
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Yes sorry i mean the bleed screw, my CH terminology isn't very good!

I've taken it out but I get a jet of water not a dribble so I quickly put it back on again,
 

CBW

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Usually a sign the pump is knackered imo
 
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The pump needs further investigation . Are you capable of removing it to examine ?
 
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Thanks for the replies all. I got a plumber involved as I had some insurance cover on my heating system and from reading the t&Cs it should be within the cover and the excess charge is probably less than any boiler parts + fitting anyway.

He changed the pump for a new grunfos one which didn't solve the issue. He ordered a new flow switch for the boiler but it won't arrive until Monday so be suggested to put some cleaner in the system and let it circulate. I tied up the ballcock of the f&e tank and drained down the system enough to empty the tank. Then I poured in a bottle of Sentinel X400 cleaner and refilled the system and bled the rads. It didn't fix the problem immediately (didn't expect that it would) but I've left it to circulate in the system with the heating programmer on (boiler is locked out and not firing but pump is running to circulate the cleaner). Also got some sentinel x100 inhibitor to put back in the system when it's fixed (there was a good deal at Screwfix 2 for £25)

Hopefully get a resolution to this on Monday.. fingers crossed.
 

CBW

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I’m not sure if it’s relevant, but having re-read, is it possible that you crossed your flow and return pipes for the towel rail?
 
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I don't think so, all I did was cut off the old pipe just below the floor and fit a couple of elbows to move the pipe centres closer (if that makes sense)
 
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He could of quite easily tested if it was the flow switch before replacing the pump at your expense, like I said in my first post if you know the system is filling back up & the cold feeds not blocked, them flow switches are a magnet for ****e.
 
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This is sorted now,

I had some insurance cover included with my gas & electricity bill, normally I wouldn't be overly happy with parts getting replaced "speculatively" but in this case it didn't matter to me financially because it was all included in the excess charge

The flow switch didn't fix the issue although it was a little corroded. In the end the problem was a blockage in a pipe between the pump and the boiler. Pipe was cut (luckily access was available under the floor as the bathroom tiles had been removed for tiling, god knows what I would've done without, cut a hole in the ceiling below I guess), blockage cleared with a rod and pipe joined again.

System refilled and inhibitor added!
 
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