Is Zehnder worth it?

[BartW]

Hi,

I am still reviewing MVHR options, and can't help but notice that likes of the Zehnder unit work out twice as much as your run of the mill Vent Axia.

 

In a nutshell, are they worth the 100% premium?

 

Thanks

Bart

[mvincentd]

I have a Zehnder q350....quick search today on google £2296 inc vat.

 

My designer offered the zehnder as an upgrade to either the;

Titon hrv10m....quick google today £1633 inc vat

or

Vent-axia sentinel kinetic plus....£1536 inc vat

 

So that halves your notion of the Zehnder premium on the vent-axia

 

BPC have an Airflow Duplexvent BV400 at £714 inc vat.  It says for houses up to 250sqm, has bypass, frost protection, humidity sensor and claims 93% recovery.....so statistically comparable.

 

Is the vent-axia worth the 115% premium on the Duplexvent?

 

Not a clue!

 

All I can tell you is my mvhr system is one of the best things about my house...but i've no idea if i'd still say that if my unit was a Duplexvent.

[Oz07]

Problem is nobody will know till they buy. Are the guarantees comparable?

I went for a cheaper unit with 2 year guarantee which has developed a fault within first few months. I've got a new one sitting in the garage ready to go when I have time but I won't hold out much hope for after 2 yr. Performance seems fine but it's the first one I've had. 

 

I put missus in charge of new fridge purchase. Came home one day and she had bought one, 800 quid with 1 yr warranty. I told her to ring up cancel the fridge purchase and took this task back under my control! (freak)

[SuperJohnG]

15 minutes ago, Oz07 said:

put missus in charge of new fridge purchase. Came home one day and she had bought one, 800 quid with 1 yr warranty. I told her to ring up cancel the fridge purchase and took this task back under my control! (freak)

That'll  teach you to let someone else make decisions. I couldnt deal with that in the first place...I'm not a control freak but I need to research everything to death before buying. 

 

My wife won't even follow the rules about where the dishes go in the dishwasher...and she always puts a tiny pan on the biggest hob ring...both which bother me each day. She isn't allowed to make technical decisions. 

 

Disclaimer: this isn't a sexist comment..its.merely one about my other half. ( I load the dishwasher!)

[joe90]

6 minutes ago, SuperJohnG said:

I load the dishwasher!

if you want a job done properly, do it yourself!

[BartW]

3 hours ago, mvincentd said:

I have a Zehnder q350....quick search today on google £2296 inc vat.

 

My designer offered the zehnder as an upgrade to either the;

Titon hrv10m....quick google today £1633 inc vat

or

Vent-axia sentinel kinetic plus....£1536 inc vat

 

So that halves your notion of the Zehnder premium on the vent-axia

 

BPC have an Airflow Duplexvent BV400 at £714 inc vat.  It says for houses up to 250sqm, has bypass, frost protection, humidity sensor and claims 93% recovery.....so statistically comparable.

 

Is the vent-axia worth the 115% premium on the Duplexvent?

 

Not a clue!

 

All I can tell you is my mvhr system is one of the best things about my house...but i've no idea if i'd still say that if my unit was a Duplexvent.

Yes, I am guessing you are comparing epicair prices. 
 

i basically looked at Zendher Q350 vs the said ventaxia. Both seem decent, but the question still remains. 
 

i could specify a (perfectly fine) ventaxia and ducting for around £2500 ex vat from BPC, or spend twice that on the (finer?) Z. 
 

I also read another post in this section by someone else earlier today where power consumption, losses, and savings were being stipulated and compared, and one could conclude that the maths could well be out of the window, the moment you open it!

 

So, from the benefits perspective is it similar to ASHP? You will have broken even in 10yrs time, at which point you start saving, ultimately meaning that it’s whatever makes you feel better and more comfortable about what you believe?

[Levo]

I am going through the same process and pain of deciding Titon vs Zehnder.

The only comparable Ventaxia is the Advance SX. The key functions for me are Constant flow and support for Pollen filter.

Finer filter means higher pressure and higher spec fans.

On that front, Ventaxia only claims support for ePM2.5 whereas both Titon and Zehnder support ePM1 filtration.

Obviously, none of the published figures are based on the finer filters.

I had the Ventaxia in my short list but discarded it due to the size of their filter which is under 500cm2 whereas Titon and Zehnder has 800cm2 filters.

The smaller the filter size, the higher pressure drop you will have = higher fan speed = more noise...

So, basically you get what you pay for.

[BartW]

The noise element (I hope) should not be an issue with our build, as I am hoping to cleverly install it in the loft storage area.

 

I know it is a piece of equipment that in theory should rarely have to be seen to, but I do like the sleek looks of the Zehnder unit

 

On the filtration front, I agree I would prefer to have the better quality there. 

 

I do like the tech, and supposedly would appreciate the smart app controls, and the ability to cool and heat if needed (probably at least cool, as the whole house will be UFH, anyway.

[Iceverge]

Have a look at the passivehaus database. 

 

https://database.passivehouse.com/en/components/list/ventilation_small

 

it gives a like for like comparison of units with regards to heat recovery and importantly unit noise. 

 

No surprise the better units are more coins.  

[DundeeDancer]

50 minutes ago, Iceverge said:

Have a look at the passivehaus database.

 

Thanks for posting the link Iceverge, I was just searching for this type of thing today due to me recently installing a single room MVHR fan and me not being too impressed with it so far.

 

I was trying to find out if any institutions independently tests and publicizes these MVHR products. I wonder if the Passive House Institute database figures are just collected for the manufacture specifications or if the Passive House ran tests to confirm the figures?

 

I don’t see any single room MVHR fans or Vent Axia items listed ?

 

Cheers, DD.

[Levo]

I just noticed this and thought I would share it here:

The PHI Test method specifically states (on page 1!): " Before the start of the testing the type and model of the built-in filters should be checked. On the outdoor air side a filter of efficiency ISO ePM1 50%, on the extract air side of efficiency ISO Coarse 60%is to be inserted."

The SAP on the other hand makes no mention whatsoever of filters. Just "unit as supplied buy the manufacturer". Meaning the test are done with Coarse 60% filters on both sides.

This would go a long way to explain the generally worse efficiency figures in the PHI database and as far as I am concerned, for me, they would be the more accurate figures.

Also, note that the Zehnder Q350 specs call for 350m3/h @ 100Pa (with G4s) but PHI states the max flow as 270m3/h which I think is related to using ePM1 (high spec F7) filters and not the G3/4.

[Olf]

On 14/11/2020 at 10:03, BartW said:

 Zehnder unit work out twice as much as your run of the mill Vent Axia.

 

It's similar story to Fiesta vs Merc taking you from A to B, but one costing twice as much.

What Zehnder offers:

- better heat exhange efficiency: each manufacturer gives you percentage, but Zehnder uses PHI methodology and is certified to it

- better specific power, which reduces total cost of ownership (I did some figures here)

- quiter operation

- advanced off the shelf controls/demand control options

- Zehnder specifically also offers nice ducting system (Comfowell) saving some space - if that is at premium (eg London), it may pay back for itself

 

For me Zehnder is really all singing all dancing solution, but I found last 2 not important and first 3 satisfied by another solution

[joe90]

On 14/11/2020 at 16:38, BartW said:

The noise element (I hope) should not be an issue with our build, as I am hoping to cleverly install it in the loft storage area.

I did this, hung it from the roof trusses, not on the bedroom ceilings, mounted on rubber feet. NO noise in the house apart from air whoosh when on boost.