Another f75

[sootydog123]

I get the f75 fault on an ecotec plus 837 so after reading many posts on here decided to bite the bullet. I drained down the boiler and repressured the expansion vessel up to .9 bar as per instructions in book.I thought I'd take a look at the pressure sensor but coulbn't get the ruddy thing out, I lifted the clip but couldn't get it all the way out because of what looks like a finned radiator thingy in the way.

I gave that up as a bad job and I hoped that just pressuring the expansion would do the trick it only had 0.4 bar in it.The thing is there was no pressure showing on the manometer but on the digi display it was showing 1.8 bar so does this mean that the pressure sensor is up the spout? To get the boiler running I had to pressure it till the digi display went up to 1.9 bar. It now works fine I'm just a bit uncomfortable with the pressure I'd like 1.6-1.7 bar in there.

Any help would be much appreciated.

 

[Beerlover]

Yep the sensor is shot. To replace it you can either remove the plate heat exchanger to give you clearance, or lift the clip as high as possible and then wrench it out with pliers. The replacement part 0020059717 comes with a new clip. To install the new one simply put the clip in from the bottom - must be a new clip though.

Either way is just as easy, post when you have the new part if you are still unsure.

 

[kevplumb]

lift the clip as high as possible and then wrench it out with pliers.

is that before of after the hammer

 

[mickyg]

need to take out the plate he. 5min job, not worth doing any wrenching imo!

 

[sootydog123]

Thanks guys I wasn't sure that the heat exchanger was that easy to remove does it not have pipes going into it?.

You gotta love this forum gives so many good answers.

 

[mickyg]

Thanks guys I wasn't sure that the heat exchanger was that easy to remove does it not have pipes going into it?.

You gotta love this forum gives so many good answers.

not exactly its got 4 rubber washers behind it. Once the water is isolated and boiler drained, open hot tap, slacken 4 screws let water drain to tap then off. easy. Always worth smearing some silicone grease on the flats of the plate he before putting it back on.

 

[kevplumb]

Thanks guys I wasn't sure that the heat exchanger was that easy to remove does it not have pipes going into it?.

You gotta love this forum gives so many good answers.

not exactly its got 4 rubber washers behind it. Once the water is isolated and boiler drained, open hot tap, slacken 4 screws let water drain to tap then off. easy. Always worth smearing some silicone grease on the flats of the plate he before putting it back on.

and didn't we all make that mistake the first time

 

[sootydog123]

Had to revert to bending the clip to get it out the heat exchanger screws were too tight to undo and didn't fancy using an impact driver on them if the exchanger ever needs changing they will have to be drilled out.

Still all done for the princely price of 20 quid.

The old pressure sensor was full of black deposits which is odd coz its always had inhibitor in and has had a magnetic cleaner in since installation.