Central heating not getting hot

[Mason9998]

Hello, recently took off a radiator to clean all the sludge out. Also put in some cleaner into the system and have since drained the system at the same time took off the heat exchanger plate and cleaned out and topped system back up. Now non of my radiators are getting hot. Boiler out pipe to radiator is roasting. Getting to the first radiator by the boiler as this pipe is also hot but not getting into the radiator. Maybe a little bit as it’s slightly warmer than clay cold. I have bled all the radiators from bottom floor up to the top with no difference (a few times). I assume I have an airlock somewhere. Wondering if it could be after the heat exchanger and before the first radiator ie in the boiler itself? Would it be beneficial to drain the system again and top it back up?

Thanks in advance, should’ve paid someone to do it.

 

[Mottie]

I’m a complete numpty when it comes to heating. I can remove rads, top up, bleed etc but I think stripping a heat exchanger plate out of a boiler to clean it seems a bit extreme to me. Maybe that’s just me though. I can’t see that removing rads, refilling and bleeding would give you those problems so it’s got to be something to do with tinkering with the boiler, surely. Isn’t that a job that should be carried out by a gas safe person?

 

[Mason9998]

Taking the heat exchanger plate out was probably easier than taking a radiator off, it’s two screws. As I said at the bottom should’ve paid someone to do it..

 

[terryplumb]

Does boiler fire up and give constant hot water when running hot taps ?

 

[Mason9998]

Yes boiler fires up, did originally have hot water taps inconsistent hot and cold water but seem to of sorted that issue

 

[terryplumb]

There is no circulation ,have you closed any isolation valves on boiler , particularly the return ? Possible air lock or pump problem .

 

[Mason9998]

Yes, I closed the isolation valve when taking the heat exchanger plate off and since put it back on. I assumed it would be an airlock. Would this be on the pump itself? Big flathead screw?

 

[terryplumb]

I assumed it was the plate heat exchanger ( for domestic hot water) that you removed,is that so ?
The central silver ,round disc on the pump would be for bleeding air from pump.
Double check isolation valves are definitely open.

 

[Mason9998]

Yes the plate heat exchanger. Definitely open. I’ve not touched the pump as of yet. Only bled all the radiators a few times

 

[terryplumb]

Bleed the pump and check it is actually spinning .

 

[Mason9998]

Thank you, by bleed the pump does the silver disk just need cracking off or fully taken out? And how do I know if it’s spinning? Through vibration or can I see it? Sorry just not currently in the house

 

[terryplumb]

Doesn't need to be removed ,just open it a little until water dribbles out. Protect wiring etc with a cloth ,and isolate electric supply to boiler before doing so.
Don't know what boiler you have ,but you may be tinkering with things you shouldn't really access if you are removing the front cover.

 

[Mason9998]

Thank you, lesson learnt. Videos make it look simple and engineer by trade, stupidly thought I’d be able to.