Vaillant Ecotec Pro pressure sensor question

[Mike13]

Hi,

As title, I have had to do a bunch of refills lately as documented in other threads.
I noticed that when I have drained down enough to be able to open the upstairs radiator bleed valve and air goes in and not out, I am seeing the display say the pressure is 1.6 bar.
That is clearly wrong, as it is at most an actual pressure of 0.25 bar.
Is it an easy item to change or is it best to do other things first?

 

[CBW]

Are you gas safe registered or retired engineer?

 

[Mike13]

No, I am only working on the bits that do not involve gas, the plumbing side is quite straightforward, and there are no fittings to undo to get access to the plumbing tray. You just tug the cover off.
I have worked on some quite high tech electronics over the years including HPLC, pumping small volumes of solvents at up to 10,000 psi.

 

[CBW]

No, I am only working on the bits that do not involve gas,

Removing the cover on that boiler is classed as gas work, as the cover forms part of the combustion circuit.

 

[Mike13]

How?? Normally for any product like that there is a tamper evident screw to undo, so that it is clear you are entering a part of the product with different regs. Seems a bit vague that the cover just lifts off with no screws or anything, no warnings on the cover either.

 

[CBW]

It might be that your screw is missing, but they usually do have one. I work on these on a daily basis. The covers don’t come with warnings, it’s all in the manufacturers instructions, and possibly the user instructions.

 

[Mike13]

Well as a separate issue, does the unit display telling me I have 1.6Bar when I have a 7 foot head of water mean that my pressure sensor is toast?

 

[CBW]

Never worked on that type of pressure value before, but yes could be toast or could be blocked.

 

[Mike13]

Well it goes up when I add water, currently also using the real pressure dial inside as a sanity check.
It used to go down low when the system was drained before, but it doesnt now.
Now that it has had a powerflush and has some x400 going round it is time to get in a vaillant certified engineer, it was reporting error codes before where all the web pages with them to check, said -- time for a powerflush.
Now that that is out the way and engineer will fix it. I had two three metre runs that would not flow anything even with mains pressure on one end straight at the end of the pipe, managed to rod those with some steel wire that was flexible enough to do the job.
Over a cupful of solids retrieved from each pipe!