Boiler receiver wiring - Danfoss RX1

[bunkotungus]

It used to work.
But the wire got tugged and pulled all the connectors out (except the grey one, that's still in the correct place).
I tried to wire it up again in the below pic but the hot water isn't coming on. Boiler is a Grant Vortex Pro External 26kW oil combi.
Since the below pics have been taken I have upped the pressure to 1.25, still doesn't work.
my rewiring of the receiver:

the boiler lights up, but when I run the hot water it doesn't fire up and remains cold:

when I hit the service switch the boiler fires up and seems fine:

What could have gone wrong here? Have I fried something inside the boiler? How should I troubleshoot this? It's a new boiler...

 

[ShaunCorbs]

Leave the front off the rx1 so just the base plate is shown what does the boiler do ?

 

[bunkotungus]

Leave the front off the rx1 so just the base plate is shown what does the boiler do ?

nothing, it doesn't fire up when I run the hot water. Only light on the boiler is the Power one.

 

[bunkotungus]

Leave the front off the rx1 so just the base plate is shown what does the boiler do ?

I'm just not sure what else to try. I'm not even sure if this wiring is right and the fitter won't get back in touch with me. The boiler fires up if I hit the test switch. I don't want to turn the central heating on cause its a new boiler and theres crud in the radiators.

 

[ShaunCorbs]

nothing, it doesn't fire up when I run the hot water. Only light on the boiler is the Power one.

Try putting the black with the browns does hw work then ?

Also why is there crud in the rads ?

 

[bunkotungus]

Try putting the black with the browns does hw work then ?

Also why is there crud in the rads ?

The rads have never been flushed or had fernox. The house is mostly plastic 10mm pipework that was botched by a cowboy plumber. A lot of it needs to be completely repiped. I just don't want to risk damaging the new boiler. I will but the black with the browns now. thank you. oh also its a single channel receiver when apparently it should've been a dual channel, that was bodged too.

 

[bunkotungus]

Try putting the black with the browns does hw work then ?

Also why is there crud in the rads ?

THANK YOU! I just put the black with the browns and the HW works like how it used to. I would buy you a pint if you lived nearer!!

 

[ShaunCorbs]

That’s easy enough if you want to swap to a dual channel programmer

Black is hot water
Grey heating
Brown lives
Blue neutral
Green earths

 

[Deleted member 120897]

As someone trying to gain more knowledge and not understanding oil boilers, how does a single channel programmer (assuming for heating) bring on hot water? Or was it wired up incorrectly?

 

[ShaunCorbs]

As someone trying to gain more knowledge and not understanding oil boilers, how does a single channel programmer (assuming for heating) bring on hot water? Or was it wired up incorrectly?

Hot water always on with oil combis it’s ideal / beneficial to have it timed to save oil eg not heating in the middle of the night / when no one’s in

 

[tamzbackforalook]

Try putting the black with the browns does hw work then ?

Also why is there crud in the rads ?

Wonderful advice.

 

[tamzbackforalook]

nothing, it doesn't fire up when I run the hot water. Only light on the boiler is the Power one.

Stick the black wire in number 4
It is a std backplate and the wiring is from left to right Neutral Live HW off CH off HW on CH on