Honest reviews: Ventilation systems; which is best Dvs, Sayr or Hrv

[Macnz]

From consumer


I prefer balanced pressure systems where the heat is recovered from the outgoing air. They are more expensive but work better and aren't the fire hazard that positive pressure systems are. Really, if you have a fire who wants deadly smoke evenly distributed to all areas of the house.

That's why the best systems shut down in those situations.

[Macnz]

So when you don't need the heat, you can move the roof space heat into the home at full speed. When the home is cold, the roof space is also cold and idles along. Doesn't seem like the extra airflow is needed at all.

Huh?

[Damap]

I went with Healthaire because I met the owner and he invented the system that all the companies now use. So his knowledge was without peer. And we are several years in on multiple installations and not one fault or problem ever. We had a few houses with real damp issues. We used to have moss growing on window sills thanks to tenants never opening windows on one south facing property. Same tenant same house now dry as a bone.
I can't say anything bad about the others only that Healthaire have been amazing, fully automated not one breakdown or tenant hassle. But I never buy on price with stuff like this, get the best you can. After talking to Mr Healthaire, (i forget his name), I was confident that A: he knew exactly what his system would and wouldn't do so no BS and B: as the creator of the system he stood behind it 100%.

[Yoshibear]

I went with Healthaire because I met the owner and he invented the system that all the companies now use. So his knowledge was without peer. And we are several years in on multiple installations and not one fault or problem ever. We had a few houses with real damp issues. We used to have moss growing on window sills thanks to tenants never opening windows on one south facing property. Same tenant same house now dry as a bone.
I can't say anything bad about the others only that Healthaire have been amazing, fully automated not one breakdown or tenant hassle. But I never buy on price with stuff like this, get the best you can. After talking to Mr Healthaire, (i forget his name), I was confident that A: he knew exactly what his system would and wouldn't do so no BS and B: as the creator of the system he stood behind it 100%.

(Yoshiko's husband here - (I'm a refrigeration engineer.)

I'm guessing you didn't get Sayr around. We had sayr, dvs, hrv and smartvent around at our house. Sayr was streets ahead of the competition as far as knowledge.

I usually make it my mission to to throw as many curly questions at sales people to see if they really know their stuff. The sayr guy was very knowledgeable, dvs was good but I like people who if they don't know the answer say 'I don't know, I will find out' The dvs guy fudged stuff a bit...the hrv dude tried to tell me they had a central google motor! I asked if he meant a Centrifugal motor? "No it's a central google motor" as you can guess I didn't buy from him. LMAO

I'd recommend sayr, if nothing else to get some good honest advice without the pushiness.

[Macnz]

Most positive pressure systems claim to recover heat from the roof space. This is possible on sunny days, even in winter, but there will only be a small amount of heat available. An Otago University study has shown there won't be warm air up there on frosty nights and cold grey winter days. To cope with this, most systems automatically slow or even stop the airflow when the roof space temperature falls below certain levels. That means your ventilation slows down or even stops, unless there is a heater fitted.

So when you don't need the heat, you can move the roof space heat into the home at full speed. When the home is cold, the roof space is also cold and idles along. Doesn't seem like the extra airflow is needed at all.

I saw this on the net too. Both hrv and sayr told me the same story; the university study was done completely via computer simulation! No real data.

Also their argument for heaters in the roof cavity; 'Why on earth would you want to heat air that's 5 degrees up to 18 degrees (lots of energy $$$$) - isn't it better to just heat the inside of the house 18 to 20 degrees (A little bit of energy $) plus the saving you make on not getting a heater, improve your insulation in your roof.

[Wayne]

central google motor! [/B]I asked if he meant a Centrifugal motor? "No it's a central google motor" as you can guess I didn't buy from him.

LOL - love that one.

[DazRaz]

I saw this on the net too. Both hrv and sayr told me the same story; the university study was done completely via computer simulation! No real data.

Also their argument for heaters in the roof cavity; 'Why on earth would you want to heat air that's 5 degrees up to 18 degrees (lots of energy $$$$) - isn't it better to just heat the inside of the house 18 to 20 degrees (A little bit of energy $) plus the saving you make on not getting a heater, improve your insulation in your roof.

I agree. No way would I put in a unit with a heater. But then I wouldn't put in a positive pressure system at all.

[Trolly]

Thanks Mac for this thread...it's been very helpful...we were looking for a solution as I didn't want another damp winter - especially with a new baby in the house. We had been tossing up between Dvs and Sayr (as stated hrv were excluded simply because they were *rude and pushy* (I won't say what I really think) We decided in the end on Sayr. If I could say nothing else about them I would say their guys who put the system in were amazing. On time, polite, took their shoes off and best of all they cleaned up...our house was tidier than when they arrived! As far as the unit all seems to be working fine - early days yet though (not really winter yet) but one thing we have noticed is the house does feel fresher and warmer - not stuffy. I will keep people posted as to how it goes over winter.

[harmonist]

I'm glad this thread came about as well, even though I'm not looking at the same sysmtems as the OP it did help with the research process. I've ended up going with a 4 oulet system from Smartvent, I'll add a 5th outlet to the large lounge at a later date if need be. I had Smartvent around for a quote and it came in at around $3200, but I've bought the same model for $1625 and will install myself. I already have a powerpoint wired to a cupboard where I have a router and all my ethernet so I'll just feed an extension cable to there, pretty straight forward hopefully. I was interested in hearing more about the healthaire system but they don't make it easy finding prices online and I don't even know if they allow self installation, oh well. I've already got condensation building up on the windows now so looking forward to getting it installed this weekend if all goes to plan!

[donthatetheplayer]

Had Healthaire around. Nice guy. Good, honest advice. He even told me their system (and no system) would get rid of our weeping windows because of the style of our windows and blinds. As Damap says no BS from these guys. Total cost was a bit more than I was wanting to spend. I'm thinking a heat pump or two would be a better investment? Would this do the same job?

I was very impressed with the service and knowledge and especially the honesty.

Edit: The unovent system I mentioned earlier comes in at $2700 plus installation. The Healthaire system is $3800 including installation. The price advantage of Unovent isn't that strong.

[ivanp]

I've contacted Unovent, they give a 20% discount to APIA/NZPIF members, which makes their 4-outlet system (for 3-bdrm) cost about $1100 (incl.GST, without installation) which makes it few hundred $$ cheaper than I can buy SmartVent.

[harmonist]

I finished installing my Smartvent SV04 last night, did it over 3 nights and was a very straightforward process, I definitely recommend having a go yourself if you don't mind spending a few hours in the ceiling. My longest duct is about 9 metres and still gets good airflow on the lowest setting which I'm happy about. Overall very happy with the system, no condensation on the windows in the 2 person room this morning, although it's been fairly warm this week, I'll be interested to see how it goes over the winter months, my roof space was sitting at 20deg this morning, thought it would be a bit colder up there in the morning but I'm sure those colder months are coming.

[Cnob009]

No No...not the wrong side of bed...Just getting a bit frustrated with the Thread. I have a simple question

1. I have narrowed to down to three systems hrv dvs and Sayr

From what I can see these seem to be the most popular and I wanted to know who has these and what they think.

So far I have only had 1 person answer my question which was "I have a Sayr and love it"

Everyone else on here seems to be trying to push something else? I Don't want anything else...just what people thought, of those three systems.

And just to help anyone else I have shortened the list...We are now only tossing up between hrv and Sayr. dvs don't have the air flow to compete with the other two.


and Airflow - "I don't care what size my engine is I just want that car"

It was put to me like this "would you tow your big boat up over the Bombays with a mini - No, not unless you had too and you're not gonna do any favors to you mini. You'd use your 4x4 or commodore. No point in under performance...better to have over performance.

hrv and Sayr seem to be the only two companies that follow a standard as far as how much airflow is needed...all the others seem to sell what ever you will buy. i.e. unovent...there is no real control just how many vents do you want...that's not cutomer service that almost snake oil... 'no consideration of how cold it is, how big the house is etc...just how many do you want.'

I applaud people who try to find solutions and make them accessible...but it has to be done right...Who would by a Cherry Car....Hey cause they are real cheap...but they have a poor reliability record and for God's sake don't crash one!

Sorry for the rant...Just after a bit of specific feed back.

I agree I'd like to know about these three systems. I'm looking at the moment and wondering if dvs with tempervent is smart or not or if the others are better systems

[Suse]

I just had double glazed aluminium joinery put throughout our house in the hope it would be warmer and dryer. little did I know. The condensation seems worse than ever so I'm really interested in a HRV or whatever type system.

[mrsaneperson]

Hi everyone,

Thanks for the feedback, which I appreciate, but as I said I have shorted listed the three products that I'm interested in, and am just interested in feedback (good and bad) from people that have those systems.

I'm sure other systems out there have their merits but usually that's price not performance i.e. dry-matic above...a friend got one of those put into his newly built house in Henderson and it didn't seem to do a damn thing...when he complained the refunded his money but never came to get it back and it's still there gathering dust. He is waiting to see what I get as he still has wet windows every winter.

But thank-you all for the suggestions anyway.

I had exactly the same experience with a Smartvent system i had installed. Damn thing never made any difference - complete waste of money! My understanding is these types of systems are not good on tiled roofs as there is too much cold air in the attic space.