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Andrew Smith
Andrew Smith, Engineer
Category: UK Plumbing
Satisfied Customers: 3591
Experience:  Domestic Gas, Commercial Gas, LPG, Unvented Hot Water, Part P Electrical, Commercial Catering
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Vaillant ecotec pro 28. Last night didn't come on and looked

Customer Question

Hi - Vaillant ecotec pro 28. Last night didn't come on and looked like the reason was that the water pressure had dropped below the minimum so I topped it up. However that didn't work, the message was showing as S30. So I replaced the batteries and reset the RF sender. It still didn't come on. So I cleaned out the magnaclean unit (which has resulted in issues in the past with it dumping the water out), and it came on - BUT the pressure rose to 4bar. So I turned it off, then checked for leaks - but now it wont come back on again .... any ideas?? The message is still S30.
Submitted: 1 year ago.
Category: UK Plumbing
Expert:  Andrew Smith replied 1 year ago.

S30 means it is in standby - no demand.

Sounds like a room stat problem, can you place the transmitter near the receiver and see if you can get them to resync?

Customer: replied 1 year ago.
They are synced. When it changes from one setting to another the ***** *****ght flashes. I'm working with it a few inches apart. I reset it last night and put new batteries in too. The green light on the receiver is solid (Siemens RDJ10RF), cheers
Expert:  Andrew Smith replied 1 year ago.

Let's try a full reset and if does not work then it is a faulty relay in the receiver and I can give you aq wire around;

http://jcbathrooms-heating.com/Siemens%20room%20stat%20instructions.pdf

Customer: replied 1 year ago.
I'm happy to reset it again, however that doesn't explain why it dropped the water pressure initially, or when I got it going the pressure went up to 4bar? Cheers
Expert:  Andrew Smith replied 1 year ago.

You may have a problem with your expansion vessel, but we would need to do some checks to confirm

Customer: replied 1 year ago.
I am worried that the S30 message could be misleading/an error. I had similar issues 10 months ago (with it dumping water) and cleaning the magnaclean device sorted that out. I have reset the RF device, and still no joy,
Expert:  Andrew Smith replied 1 year ago.

To prove this we can wire around the stat if you have a small screwdriver?

Customer: replied 1 year ago.
Expert:  Andrew Smith replied 1 year ago.

If you take off the cover and expose the wiring.

Let me know the connections you have and the wires in them

Customer: replied 1 year ago.
should I turn off the bolier at the wall first?
Expert:  Andrew Smith replied 1 year ago.

Just so the lights go off on the receiver

Customer: replied 1 year ago.
they are on the same power link (i.e. the receiver is powered via the bolier)
Expert:  Andrew Smith replied 1 year ago.

ok fine

Customer: replied 1 year ago.
I should turn the whole unit off?
The wiring from the receiver goes straight into the back of the control panel on the left hand side adjacent to the mains power cable. Two other groups (of about 6-8) smaller wires also enter the control unit just above. Is there anything in particular you are looking for?
Expert:  Andrew Smith replied 1 year ago.

The receiver will have power and a pair of switch wires inside.

Customer: replied 1 year ago.
it has 4 cables - black grey blue and brown, that enter the boiler - in positions 4,3,n,l respectiely
Expert:  Andrew Smith replied 1 year ago.

Ok, if you take the wire out of 4 and put it into terminal 3 also.

Turn the power back on and see if the boiler fires for heating

Customer: replied 1 year ago.
no, it made noises as if it was (I pressed 'I' and showed as S 27. But then it stopped and back to S30. The receiver is showing as red, but if I move the settings on the transmitter, that sends it back to green (not sure if that is relevant!). Cheers
Expert:  Andrew Smith replied 1 year ago.

It doesnt matter what the receibver is saying now as you should have linked it out

Customer: replied 1 year ago.
would you think that that rules out the receiver as the issue?
Customer: replied 1 year ago.
are you waiting on me for anything?
Expert:  Andrew Smith replied 1 year ago.

It would not let me answer?

If you have the receiver linked out then it will be a boiler fault.

When you turn the heating on on the front of the boiler (heating and hot water) what does the boiler do?

The first thing that should happen is the pump should start

Customer: replied 1 year ago.
Hot water is fine. Its the central heating that is the problem. For heating, either nothing happens, or it starts 'wirring' then stops. I will put the wiring back for the receiver then.
Expert:  Andrew Smith replied 1 year ago.

We need to find why the boiler does not think there is a demand.

What is the system pressure reading?

Customer: replied 1 year ago.
1.5 bar presently. As I say, when I did get it working earlier, it moved up to 4bar - which worried me. So I do wonder if that's the issues.
Customer: replied 1 year ago.
Should say, the system was thoroughly cleaned and had inhibitor put in just 10 months ago.
Expert:  Andrew Smith replied 1 year ago.

Perhaps the pump is sticking?

If the pump was sticking and the boiler starts then it could quickly overheat and the pressure would rise really quickly.

Try this;

http://www.vaillant.co.uk/downloads/ecotec-pro-instn-maint-261423.pdf

Page 54 onwards

Customer: replied 1 year ago.
Not sure what I am looking at, can you clarify what you want me to do? Wouldn't a pump failure show a fault (F code).
Cheers
Expert:  Andrew Smith replied 1 year ago.

I think you are the stage where you have proved it is nothing basic and well done for staying with me during the process.

Perhaps you should call someone tomorrow to run through why the pump is not running when the heating is demanded.

Customer: replied 1 year ago.
I know its getting to the stage where there is little left to try. Appreciate your help. I have just seen something in the doc you sent - about a P1 diagnostic test.
Should I give that a go:Code Test Program Meaning
P.1 Test Program used when the unit runs at full load after successful ignition
P.2 Test program used when the unit runs with minimum gas consumption after successful ignition
P.5 Program for STB (Safety Temperature
Expert:  Andrew Smith replied 1 year ago.

Any tests you can do will help anyone that comes eventually to look at this, perhaps you can even sort it yourself by working through the diagnostics

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