Help needed on Nibe F1245-8 heat pump information messages

Betyar

Hi Everyone!

I use a Nibe F1245-8 brine-to-water heat pump and every time the Anti-Legionella treatment kicks in I have a series of disturbing messages.

The Nibe service says that I should not worry about them as these are only information messages.

I wonder why would Nibe call a "High pressure alarm" an Alarm and log it if it is how the HP should work normally?

My warranty on the HP is due to expire in a couple of months and I am i little bit weary that this might lead to a serious fault after my warranty expires.

Anybody has similar problems with Nibe heat pumps?

Many thank everyone!

Reed_Richards

Perhaps as the water in your cylinder gets hotter it heats the water from the heat pump flowing through the coil in the cylinder, the opposite of what normally happens but happening because, I presume, you have an immersion heater which comes on to finish the Legionella cycle.  If so the water from the heat pump will get a bit hotter than it is in normal operation, which will raise its pressure.  Perhaps that is what triggers the alarm?

Brine-to-water sounds really fun; there can't be many of those in use.  @Screwdriva, this is what you should have got.  

Screwdriva

Reed_Richards said:

@Screwdriva, this is what you should have got.  

Incredibly happy with the Viessmann 200-W. Will wait to see how heat pump technology evolves before taking the plunge! 

fisher66

I have a NIBE heat pump and a couple of years ago I got a similar problem when running the legionella purge.  The system was 6.5 years old and had 6 month warranty left. I raised it with NIBE and it took them the best part of a year to find the problem and fix it.  It turned out the the heat exchanger in th ASHP had got clogged up with debris from the radiators/pipework etc. This was then causing the pressure sensor in the ASHP unit to decide the pressure was too high and for it to terminate the purge. NIBE insisted that I had the pipework from the circulating pump to the ASHP and back power flushed at my own expense by my installer and also a magnetic cyclonic filter added into the circuit (it only had a basic strainer filter previously).  This did not solve the problem. Eventually after about 6 engineer visits NIBE came out with a guy from Fernox and a "new" machine they had developed to power flush the ASHP heat exchanger specifically . They connect this machine directly to the flow and return sockets on the outdoor unit.  After running this for a few hours the problem was solved.

So NIBE do know all about this issue and why it occurs. I dealt mainy with Chris Easton who was their Technical Manager.

Reed_Richards

That's a very helpful reply from @fisher66 , but I'm surprised they didn't have a magnetic filter fitted in the first place.  I thought most heat pump manufacturers would mandate that one be fitted.  

fisher66

Yes - I am now surprised that a magnetic filter wasn't part of the original install, but at the time it didn't cross my mind. The installer got all the parts supplied by NIBE I believe, so I wouldn't be surprised if more people have this problem. 

I would also caution anyone who has this problem to keep an eye on the number of compressor starts the ASHP is doing daily as the automatic recovery from the High Pressure warning on my system involved it retrying the same operation multiple times until it finally gave up after the a number of attempts. This is obviously putting strain on the compressor.