maybe thats why they say not to have lossnay in wet areas, the cores are really crappy and cannot handle getting wet.

tweake:

 

maybe thats why they say not to have lossnay in wet areas, the cores are really crappy and cannot handle getting wet.

 

In a blunt way I think that hits the nail on the head, they can't handle the excess water vapour from a steamy shower. It probably condenses in the ERV core where the hot moist exhaust air hits the cold outside air.

This is why I chose to keep the bathroom fans in my place with an Lossnay ERV. We run these when having a shower. 

I wouldn't say that the cores are crappy, just that the treated paper core not suitable for excess moisture. 

Paper is brilliant for heat transfer efficiency. I remember going to a Mitsubishi Electric Lossnay presentation a few years ago. They got you to roll up a piece of paper and grip it in one had and blow through it to feel the heat transfer from your breath to your palm.

Kickinbac:

 

In a blunt way I think that hits the nail on the head, they can't handle the excess water vapour from a steamy shower. It probably condenses in the ERV core where the hot moist exhaust air hits the cold outside air.

 

This is why I chose to keep the bathroom fans in my place with an Lossnay ERV. We run these when having a shower. 

 

I wouldn't say that the cores are crappy, just that the treated paper core not suitable for excess moisture. 

 

Paper is brilliant for heat transfer efficiency. I remember going to a Mitsubishi Electric Lossnay presentation a few years ago. They got you to roll up a piece of paper and grip it in one had and blow through it to feel the heat transfer from your breath to your palm.

 

other brands paper cores can handle being wet. eg fantechs instructions say to put the core under the kitchen tap and pour water through it to clean it.

the houses that erv's are designed to be used in, you can't use bath fans. so you have to use the erv as the bath fan. it sounds like mitsi are generations behind the game.

tweake:

 

other brands paper cores can handle being wet. eg fantechs instructions say to put the core under the kitchen tap and pour water through it to clean it.

 

the houses that erv's are designed to be used in, you can't use bath fans. so you have to use the erv as the bath fan. it sounds like mitsi are generations behind the game.

 

Mitsubishi's ERV models do seem basically unchanged from their marketing from over a decade ago unfortunately.
Seems like they've been investing in the HRV space.

Fully locked in with the ERV now. Price is eye watering for the entire setup,, but hopefully worth it.

Going to have it all installed next Tuesday. Will let you guys know how it goes.

Really appreciate all the support and being super patient with me. I went from understanding nothing to learning a shit ton about HVAC.

AlDrag:

 

Fully locked in with the ERV now. Price is eye watering for the entire setup,, but hopefully worth it.

Going to have it all installed next Tuesday. Will let you guys know how it goes.

Really appreciate all the support and being super patient with me. I went from understanding nothing to learning a shit ton about HVAC.

 

So what was the final setup/layout and ballpark cost?

Ragnor:

So what was the final setup/layout and ballpark cost?

timmmay: That's a pretty good price for all of that! What supply diffusers did you end up choosing? Are you going with undercut doors or some kind of vent, or is that decision deferred?

ok so it's all installed now.

Very disappointed with the performance...it could be the attic temperature (my own temp sensor reported 38 degrees up there at 4pm today!). But it also might just be an under specced unit, 5/6kw.

It's super quiet, which is nice, and definitely pushing air, you can really feel it under the doors when standing next to it, but the room just doesn't want to drop below 25 degrees.

Also all the ducting is just laid on the ceiling. Is that normal? I thought duct work is supposed to suspended to avoid moisture or something?

Will see how it goes tonight, but if it can't handle a mild-summer, that's depressing.

timmmay: It should be able to cool the area is specified to down to a reasonable level, say 21 degrees. If it can't you should get the installers backto make it work properly. They should have tested it before they called the job done.

Yea it just doesn't seem to get below 25 degrees....they did test it, but I guess they deemed it normal idk...

Will definitely be contacting them though. Surely it should be able to reach 21 degrees even on a super hot day.

AlDrag:

 

ok so it's all installed now.

 

Very disappointed with the performance...it could be the attic temperature (my own temp sensor reported 38 degrees up there at 4pm today!). But it also might just be an under specced unit, 5/6kw.

 

It's super quiet, which is nice, and definitely pushing air, you can really feel it under the doors when standing next to it, but the room just doesn't want to drop below 25 degrees.

 

Also all the ducting is just laid on the ceiling. Is that normal? I thought duct work is supposed to suspended to avoid moisture or something?

 

Will see how it goes tonight, but if it can't handle a mild-summer, that's depressing.

 

check the basics first. put temp sensor next to the thermostat, check how cool that location is.

is the downstairs heat pump also running?

is the aircon been running most of the day? they are not really sized to cool down a room that gotten hot, which no doubt most of us do. they should be sized to maintain the temp when running all day. one issue can be its sized for heating in winter and most models are worse at cooling than heating. that can be problematic with kiwi homes typically having excessive windows.

did you see them use a tank to add gas to the system when they plumbed it up?