Strange Happening Danfoss FP715 Programmer. Do you have one?

[stem]

I have one of these wonderful devices, infact I've had three that have all manifested the same fault. The one I have is now out of warantee, so I'm wondering what to do now.

The unit works perfectly, until I have an interruption to my power supply of less than one second. The sort of thing where all the lights go out, but before you realise they're off they're back on. When this happens the display goes blank and the heating and hot water are turned on. (even if they were off before the power failed)

If the power outage is longer say 1 or 2 seconds this doesn't happen, the display shows "no1" when power is restored and then reverts to normal.

My original unit had been installed about 2 months when it first happened, so I got a replacement from the supplier the second unit did exactly the same thing so I wrote to Danfoss explaining my findings and they merely sent a third unit without explanation. This unit has also done same thing.

Having had three units all the same I think this is a design fault and needs to be addresed. I don't see the point in changing it again for another faulty unit. anyone else had this problem? or managed to resolve it?

 

[doitall]

If it doesn't have a battery back-up, it will revert to the default settings.

 

[stem]

It does have battery back up and stores the settings no problem when it's been turned off for several hours, it's the quick blip of less than a second that causes the problem. One of them turned on the service due buzzer too, and that wasn't even selected to operate

 

[Agile]

I am not surprised that it does not respond correctly in that situation. Its not an expected encounter and probably not even tested for during design/production.

However, why are you getting so many of these momentary interruptions to your supply?

If its genuinely a local area problem, shouldn't you contact the supply company?

Even in Bulawayo where there was usually an outage of an hour or two every day, there were never any momentary blips like that.

Tony

 

[stem]

It's not that often, maybe 2 or 3 times a year. My DNO say it's because I live in a rural area! (7 miles from Nottingham city centre!!! )

It's come to the fore again now because it did it while I was away, needlessly heating the house and water 24/7 in my absence. Pity because the programmer has a useful "holiday" feature which was set to turn everything back on the day I got home from my hols!

 

[Garfeild]

I have frequently come across this problem,seems to be an inherant fault with this particular unit.
Pressing the reset button with a pointy thing usually does the trick,but i have had a few that refused to reset (including my own) and ive had to replace the unit.
I suspect Danfoss must know about it.

 

[mikesjn]

We had a fault that caused this on our timer, also an FP715,and had to have a new timer because it wouldn't reset, we had the same model installed as it was just a quick swap. This does exactly the same thing, but only for like a power blip, not power loss. The problem is that when this happens the room thermostat is bypassed and the heating is just controlled by the boiler thermostat. My wife is worried, she will not go away for Christmas and leave the boiler on, so she will not go away incase it freezes. It happened last night, 2nd time this year, it was such a slight fluctuation that the clocks didn't reset. If I power the mains socket off it rest perfectly, no need to alter settings etc. Seems we are not the only ones. Has anyone any ideas.

 

[Agile]

Its clearly a design fault with this unit. The makers will know about it but will probably not admit it.

Depending on the age of the unit you could try to get the manufacturers to replace it with a different model or another make.

You should use the argument that it is not suitable for use in a rural location because of this design fault.

Tony

 

[mikesjn]

Thanks Guys, I have emailed Danfoss, if I get a reply I will post the reply.

Regards

Mike

 

[stem]

Thanks Guys, I have emailed Danfoss, if I get a reply I will post the reply.

Mike, let me know the contact details you used and I'll get in touch with them again as well, the more that contact them about it the better.

 

[mikesjn]

I emailed them, but this is all the contact details from their website:

Danfoss Randall Limited
Bedford
Ampthill Road
MK42 9ER Bedfordshire
United Kingdom
WWW-Address: > www.danfoss-randall.co.uk

E-mail Address: > [email protected]

Timezone: GMT +0
Dial code: +44
Telephone: 01234 364621
01234 219705
Office Hours: 08.45 - 17.15

 

[mikesjn]

I did also send them a link to this thread. I have also found other people on the web saying they are getting the problem.

 

[mikesjn]

Getting nowhere with Danfoss, they are not replying.
Can anyone recommend something to replace this, I can do it myself, I am not an electrician, but I work with electronics, so hopeffully i can work it out. I just want a simple timer that does not do this

Thanks
Mike

 

[Hugh Jaleak]

I've a Siemens (Landis & Staefa) RWB9, find it straightforward to programme and use. It may have been superseded by the RWB29, but this offers similar options to the Danfoss. Mine replaced lot older equivalent, but I think that was about 20+ years old when it finally died.... The RWB9 has been giving me faultless operation for the last 4 years, if it lasts as long as its predecessor I wont be complaining.

I would suspect you may need to rewire the new backplate to suit, but unless you opt for another Danfoss this would probably be an issue with any different manufacturer's product. I should be able to post a copy of the wiring diagram for the RWB9 if any help.

 

[mickyg]

the danfoss backplate is the standard one, so you could fit a drayton lifestyle or tempus on the same backplate. I had to replace a 715 I fitted myself the other week because it was completely dead after 2 weeks. Put it down to a 1 off as I use alot of danfoss stuff and thats the forst failure on any of their products this year. Now I'm worried about this thread as I reckon I must've fitted at least 20 715s in the last 6 months.