Need to replace faulty Honeywell ST9400C

[bfgweb]

After providing an explanation and serial number to Honeywell only yesterday I received a pleasing email this afternoon. They have put free replacement programmer in the post to me. Coming from the Netherlands so need to be patient, but very impressed with Customer Support at Honeywell. 10/10 Honeywell for taking your customers seriously. 10/10 for this site pointing me in the right direction and specifically dreadnoughtheating for identifying the suspect batch numbers.

 

[DrPeterVC]

We had new central heating system put in in 2012. Vaillant system boiler and Honeywell controls. Intermittent fan faults on boiler (usually when freezing cold). Numerous call outs and various parts replaced.

But odd times heating not coming on and sometimes not enough hot water with no reported boiler faults. Searching for controller faults came up with this thread. It turned out that the controller had 1122 on back. Last Monday could not get hot water on at all though c/h worked OK.

On phone to Honeywell and exactly same experience as others here. They did ask if I had proof of purchase but as I did not said it would not be a problem. They suggested turning light off completely and this did get the relay working but still could not get both on at same time. Ran it manually with either hw or ch until new one arrived (from NL) on Friday.

New one seems OK (1604) hoping it will last for many years to come.

Not been very lucky with what should have been a high spec upgrade to heating.

Honeywell customer service 10/10 BUT really there is something wrong with their quality control that there are so many faulty units out there. Fortunately this was not a safety issue .

 

[Ricardo shillyshally]

Thanks to this forum & thread, I was able to get hot water/ heating (after being without for a couple of days) by turning of the backlight. I was able to get the date code and contact honeywell, who are sending me a replacement as we speak.

 

[El Barto]

So the fault reappeared yesterday after a few months of working with the backlight option turned off.

I've ordered the replacement capacitor as per Dce's post and will update here when done.

http://www.ebay.co.uk/itm/B32922C36...158404?hash=item3f53942904:g:-s0AAOSwEetV9ZOO

 

[bfgweb]

Capacitor replacement didn't work for me. Email contact with Honeywell ... replaced unit received within days ... free replacement due to my 'faulty batch' number. Good luck with capacitor, it's so frustrating when heating systems fail.

 

[El Barto]

Capacitor replacement didn't work for me. Email contact with Honeywell ... replaced unit received within days ... free replacement due to my 'faulty batch' number. Good luck with capacitor, it's so frustrating when heating systems fail.

Hmm, that's a concern but it's ordered now so I'll try first.

I've emailed them now so let's see what comes of it, from the earlier posts it looks like the after sales service is pretty good.

 

[El Barto]

UPDATE: Well that was resolved quicker than I expected...

I sent a message to Honeywell UK yesterday and got the standard auto-response, followed by a polite but formal email this morning requesting where and when it was bought, who installed it etc and a couple of pictures so they could see the batch reference.

I sent back the required info and within an hour got a reply saying thank you very much we'll be posting a replacement out to you which should arrive within a week. I also need to send them the faulty unit so luckily I haven't replaced the capacitor yet.

Exceptional service, don't you think?

PS anyone want to buy a capacitor....?

 

[3712]

Many thanks to all posts, this post has helped me diagnose my Honeywell 9400 which continuously cycles through a reset every few seconds. I have switched off the backlight today and will monitor but presently everything appears to be working. For interest to anyone else my build date shows 3712, which means it's newer than the originally mentioned 'dodgy' batch dates.

 

[MartyJW]

As per the last post my hot water stopped firing. Collected replacement on way home. Old one was 1245 production date.

 

[B19]

if you take the clock off the back plate (two grub screws underneath and lift/lever gently off the plate), there is a serial number/data badge.

The 'dodgy' batch is 1037 - 1139.

As per others, have had to change a few.

DH

Hi I can't find a number like this. All mine has on the back is st9400c1000 and it has a long number 50022735-005. Can you please advise?

 

[ianmcd]

I have a problem with my Honeywell ST9400C and read the info on this site. Thank you to all those that posted about the faulty batch from 1037 - 1139.
I've just come off the phone with Honeywell and they are sending me an FOC replacement. It will take approx 7 days to arrive from the Netherlands.

FYI the date code can be found without removing the unit from the back plate. Set the main switch to run and hold the plus(+) button until the code is displayed on the screen. Ignore the "Invalid Code" displayed and the return to the normal screen. Just keep holding until the code is displayed. My code on the back plate read 1112 and the display read 12 11

This date code display screen will automatically return to the normal settings screen.

 

[muggles]

Hi I can't find a number like this. All mine has on the back is st9400c1000 and it has a long number 50022735-005. Can you please advise?

If yours is part of the bad batch it'll be well out of warranty by now - this post is 6 years old