Vaillant f75 error; plumber wants me to choose next step

[partyon]

Hi ladies and gents...

For the last few days I've had error 75 on my vaillant ecotec pro 28 boiler. Bleeding the rads and resetting the boiler got me 24 hours of use but then the problem returned.

My usual plumber has kindly called in to look at it on his way home but as he doesn't usually do repairs he wants me to choose the next step in the repair process. He thinks changing the pump will fix it but it's not definite. He thinks it's the pump because the pressure display rises by 0.2-0.3 bar when the pump starts but it seems to sometimes not quite create enough pressure to fire the boiler. We actually watched the pressure rise on the display but not hit the magic number and on the occasions it hit the pressure needed the boiler fired.

Does the pump seem the likely culprit or should I try some cheaper options first?

Thanks for your help.

 

[Mark Br]

You need a gas engineer. Don't be in a hurry to change that pump !

 

[picasso]

Check the expansion vessel before you change anything .

 

[holtster]

I had a similar F.75 error last week. The plumber who installed the boiler called out a Vaillant Engineer. He replaced the pump, a valve and a filter. It's been working Ok for a week.

 

[partyon]

Thanks for the replies. The plumber said it wasn't the expansion, he told me the reason why but I can't remember fully. Something about when he did something it didn't cause an overflow, I think.

I would be happy to get a boiler repair man in, I just feel bad on my normal chap. He lives nearby and has popped round at short notice in the past, fixed something, and not charged me. I feel he deserves the work, even though he's always busy.

@Holtster. We're you in guarantee? If not what was the cost? Cheers.

 

[Mark Br]

It's your call, but an experienced engineer would know if it's the pump! or something else

 

[St0rmer66]

I wouldn't be in any hurry to change the pump either! Bet it's got the stupid rubber hoses!

 

[partyon]

@Mark. Thanks, I think I'll make a few calls tomorrow. My usual plumber admits that as he doesn't do repairs he doesn't have the knowledge of a call-out guy.

 

[nortonj]

Converting the rubber hoses to copper and changing pressure sensor usually sorts this, if you've ruled out the expansion and pump.

 

[Mikefromlondon]

A friends vaillant ecotech boiler had similar issues with F75, it turned out to be his sleeve filter heavily clogged with sludge. His issues started with lack of hot water and kettling noises, but his CH ran ok.

 

[St0rmer66]

Mike, you are incorrect. The case on a vaillant ecotec forms a seal for the combustion chamber and should not be opened by anyone not qualified to do so. Whether you think that is correct or not, it is a fact.

 

[Mikefromlondon]

Stormer, indeed, I edited my post. No further issues.

 

[Gasguru]

If your plumber is gas registered then he could join the combustion chamber where he will find a wealth of info on F75. Of course if he's not registered he shouldn't be looking at the boiler.

 

[partyon]

He is registered he just doesn't do many repairs. Anyway, I've been too busy to get anything sorted today so I'll just have to hope the boiler survives the weekend

Thanks everyone, I think I'll hold off on the pump and maybe give vaillant a call on Monday.

 

[Agile]

Why do you want to call Vaillant?

Or you want their £300 repair?

Much cheaper to call an independent !

One I did last week was only £112 as that involved a part. Most are just £84.

Tony