COMBI BOILER PUMP - FOUND LIVE IN NEUTRAL & neutral in l

[zappastix]

Hi

On Sunday I had a problem with electrics on a 'new faulty replacement combi boiler pump'.

I contacted the 'Electrics UK' forum, who were helpful.

There is a few outstanding questions that as Gas Safe/Corgi you hopefully might be able to help with.

Since Sunday the pump company have delivered another replacement (and picked up faulty unit).

The new pump was faulty because on the electrical side on the mains connector block the orange push
down connectors that open to clamp the soldered end wires - two of these would not open and were very
weak with no spring action.

The direct replacement pump is UPS2 Grundfos 15 - 50/60 130 6m.

This REPLACEMENT SECOND NEW PUMP has come supplied with a long "suppression lead".

This long lead will make it easier to wire up the pump away from boiler but this throws up another question.

THESE QUESTIONS - THE ELECTRICAL UK FORUM COULDN'T GIVE A DEFINITE ANSWER TO

When I went to disconnect the OLD pump I saw that the LIVE and NEUTRAL wires
were connected the wrong way round (live in neutral connector).

I was going to connect as the original pump was wired up i.e. the wrong way round but then I thought if I
do this and it blows the new pump I wouldn't be able to send the pump back as faulty.

It has been wired up back to front for at least 11 years, so it was working ok.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
I'm sure somewhere long ago that I read that swapping the 'neutral and live' around in certain
situations this is possible - but I didn't want to take the chance.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

So I'd appreciate just a few more answers;

1)

Should I follow the WRONG way round wiring i.e. live to neutral connection and neutral to live
connection OR WIRE UP as it should be i.e. NEUTRAL to NEUTRAL etc?

2)

When I connect the long suppression lead to the main cable coming from the boiler I am going
to use a CHOC BLOCK that I have here for Halogen lighting.

I cannot see any other way of connection directly to the boiler.
Or is there another way?

3)

Does anyone know what this suppression lead does?

The boiler is a: ALPHA CB28 LPG

If you want to read the original post it is under;

HELP WITH "SLOW BLOW FUSE" AND CONFUSING SITUATION
(posted Mon Sep 22 2014 12:12 pm)

Many thanks in advance.

Regards

Stephen

 

[Boilerman2]

If the flying lead is supplied with the pump then it MUST be fitted (original versions of the UPS2 had internal suppresion but this was problematic so a loose lead was supplied.

You say the N & L are the wrong way round, but how do you know this, have you checked using a multimeter between L-E & N-E to confirm? you really can't go by the colours of the wires, especially on Italian boilers!!

 

[Bunnyman]

All vaillants old ones were reversed,

 

[zappastix]

FOR ANYONE WHO READS THIS;

The onlinepump site were so helpful and delivered a replacement pump the next morning.

Unfortunately, this pump came supplied with a suppression lead and no help with what to do with regards to boiler end cable.

I phoned Grundfos today to double check as I'd already connected to a CHOC Box will block inside, just to see if that was okay - they said yes.

Technical support said although this was a new pump - the suppression lead is old technology (it controls voltage to pump).

Anyway I fitted the pump head, connected the cable the right way round (live to live etc - as the old pump had been wired up back to front).

Although the Alpha slow blow fuse (FA2) was okay I'd brought two more at £1.40 each but next day delivery was £25 - yes £25 - I paid £10 and still got next day.

Put in new fuses, filled up the system and the boiler still didn't work. I checked all the connections best I could (no meter), but everything points to PCB - it is not worth paying out for a new PCB (boiler is to old) so I'll try and sell pump on eBay and now we'll have to buy a new boiler.

It was the worth the gamble but I lost on that one.

 

[zappastix]

Sorry Boilerman2 - just picked up your post, I didn't know Alpha were Italian, even so I thought they'd have to comply.

But as you might read, were going to buy a new boiler.


Thanks to all that helped.

Stephen