Vaillant ecotec plus 438 no heating or hot water

Many thanks.

Am I right in saying to test whether the programmer has live, this will be done by opening the programmer or will there be a live in the junction box in the loft where the wires for the pump and valve are?

Obviously to test whether the 3 port valve is getting 240v this will be done at the junction box.

Would you test for continuity between programmer and 3 port valve or does the receives 240v when the programmer is turned on?
Eh, er,

I think you need an electrician tbh.
With all due respect.
 
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Problem is back.

I've honestly had enough with it!

Calm, logical testing, will find out exactly where it is failing. Throwing replacement parts at it, is doomed to failure.

I assume you have some sort of Multmeter? Set it to any range above 250v, and on an ac range. Maybe 500v, or 1000v ac.

Connect one probe firmly to known earth, the copper pipework might do for that, but there is a risk of the RCD/RCBO tripping, if you have them fitted, during your tests. In that case, you will instead have to connect to a definite neutral somewhere. Easy way, is an IEC/type kettle plug, plugged into a 13amp socket.

Then wait until your heating fails, and go down each of the terminals of the box, writing down what voltages you see. Post that here, with a good photo of the box and connections, so the experts here can interpret what the issue is.
Problem with the block connectors is you can't test an individual wire you do it by the screws and there's multiple wires sometimes in one connection.

You don't need to disturb any of those connections, just touch the tip of the probe, against the screws, and report what you find, as above.
 
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Maybe rule out the new pump as a start in case it is a dud, there should have been a new cable supplied with this? if so, just unplug it at the pump, connect a 3 pin plug at the end of the new pump cable, plug the new cable into the pump, plug the 3 pin plug into any convenient room socket via a extension lead and switch on for 10 secs or so, ensure pump starts. You should also check the s parameters in the boiler menu as these can give useful info.
Basic Y plan, below, as suggested,some simple tests can then be carried out.

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Guys, there is a delay in the pump and boiler starting. Turned the hot water on and pump and boiler kicked in 30 mins later despite the cylinder stat calling for heat.

This delay has been happening this week whenever heating or hot water is turned on. Sometimes it works straight away.

When heating is turned on there is 240v at the green wire when tested with the orange wire.


The grey wire always has 240v even when nothing is turned on at the programmer.

The valve clicks as it should when heating or hot water is turned on.
 

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The next time you get that delay, check the s parameters, if S.0 is displayed then there is "no heat demand" and we can take it from there.
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Sounds like the programmer, if it’s affecting hw and heating. get ya multimeter out
 
Hi I only got a s.30 code. This code is present for heating or hot water
The boiler will (should) have a permanent Live, a switched live, a neutral, and probably a earth.
When you switch the boiler power on then even with neither HW or CH requested at the programmer you should get power at the boiler and 230V between the PL (permanent live) and N (neutral), check this first at the boiler.
The SL (switched live) gets its signal (to start the boiler) either directly from the programmer or from the orange wire from the 3 port valve if CH only is required, the boiler PCB also controls the circulation pump.
Request HW only on, ensure cylinderstat calling for heat and test between SL and N, if no 230V...
Request CH only ON, ensure roomstat calling for heat and again test between SL and N.
 
How do I measure at the programmer

The same way - always from a known reference point, always. Connect/clip the black probe, on to the earth terminal, if there is one, or use the earth terminal of a nearby socket, then check and report the voltages you measure on each terminal.
 
The same way - always from a known reference point, always. Connect/clip the black probe, on to the earth terminal, if there is one, or use the earth terminal of a nearby socket, then check and report the voltages you measure on each terminal.
Ah!! Issue is it's decided to work again so hard to check.

Obviously if I remove the programmer to check the wires i won't be able to select heating or hot water to check once selected?
 
Ah!! Issue is it's decided to work again so hard to check.

Obviously if I remove the programmer to check the wires i won't be able to select heating or hot water to check once selected?
You don't have to do that if you do it in the way I suggested when next it occurs, the fault may not be with the progammer but at the boiler itself, if you have 230V between the SL & N or earth then probably something in the boiler itself.
At least locate/see where these connections are and if easibly accessible from underneath the boiler.
 
Ah!! Issue is it's decided to work again so hard to check.

Obviously if I remove the programmer to check the wires i won't be able to select heating or hot water to check once selected?

All of the wiring, goes to your strip of terminals in that box, in your airing cupboard, which is why you were asked to check them there..
 

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