Service visit to Viessmann Vitoden 200 with plate heat exchanger separation

Service visit to Viessmann Vitoden 200 Hydraulically isolated via plate exchangers.
A job with an interesting history. The original boiler installed at this property had constant breakdowns caused by the build up of scale within the boiler. Three years ago a new Vitodens 200 was fitted and hydraulically isolated by replacing the old low loss header with plate heat exchangers. The new boiler now protected from the introduction of contaminates from the system is clean and undamaged and running as designed.
#viessman #plate heat exchangers

[@1991elliot]

Hi Andrew, my comment on your other video re SWEP plates, these two here are actually part of the SWEP E8 series.

[@jamiewilliams685]

Great video.

[@ashbyts3900]

Hi Andrew, Great video a few queries regarding domestic use. I currently have a Viessmann 200 W installed with a Spira-Cross low loss header fitted, light industrial pump to add to the circulation but in just over 3 years I've ditched two heat exchange plates. I've spoken with the plumber regarding dirt separation but the header should take care of this, I've also mentioned the hard water within our area and possibly installing a water softener. Do you think this could help??

[@normanboyes4983]

Really interesting Andrew. I think you have most definitely got to the bottom of it. I have often thought that water chemistry maintenance is the achilles heel of a traditional wet central heating system, which forms multiple cells between copper pipework and steel radiators. Your hydraulic separation is effectively protecting the boiler by removing it from the influence of the corrosion cells and acidic effects.
I would expect in ‘traditional’ systems it is likely that primary circuit water is acidic even in serviced boilers.
Have you done any assessment on the effect on thermal efficiency of introducing the plates?
Of course the improvement in reliability (and life) of the boiler is the no brainer criteria.

[@andrewmillwardwatford9410]

We get a 3 or 4 c temperature lift across the plate but are already using low temperature design so a very small compromise. A direct system will loose efficiency in the main heat exchanger due to fouling I believe leading to far greater efficiency losses. The systems are ph adjusted to 9.8 if no aluminium is present.

[@normanboyes4983]

@@andrewmillwardwatford9410 Thank you Andrew - excellent.👍

[@Benzknees]

Would a low loss header also do the job of equalising different flow rates & collecting dirt in the system? What are the criteria for choosing either this solution or plate separation?

[@andrewmillwardwatford9410]

Yes almost the same

[@Sash_Window]

Plate separation, I'd like to know more on this please.

[@andrewmillwardwatford9410]

What would you like to know ?

[@dominichalliday8929]

Hi , if the water was clean and properly dosed how was it damaging the previous boiler?

[@jamiewilliams685]

Good question.

[@andrewmillwardwatford9410]

Im not a chemist but have looked at water quality and treatment and found that some systems just can't be cured. Rather than chase my tail seperation is a total fix for the issue.