Venmar 1.5es Constructo problems

[James547]

So I need some help badly and if this is not the place then let me know and I will move along. I am not an installer or a tech but I am having some issues and I really need some tech expertise to help me out with them as I think my installer is screwing me around.
So here are my questions/issues:

1. I have a 4200sq/ft home ICF build brand new. 5 bedrooms and 3 baths. average ceiling height is 10ft on main floor and 8 in basement. The installer put a Venmar 1.5es Constructo in the house and ran 5in main trunk and 4 in offshoot lines. Is this unit even close to big enough?

2. System ran good for about 3 months as we finished the build and for the 3 months it kept the humidity down around 50-55%. The installer came back at that point and installed rigid 90's on the unit and put the diffusers on the ends. Since then it has jumped to near 70% humidity almost over night and even with a full on dehumidifier it can't get it below 64% in the basement. The Installer said that the system didn't need to be balanced it would auto balance itself. Thoughts?

3. We asked for a unit that could dehumidify and the installer said that this unit would told us it was more expensive that the on he would normally put in. Will this unit do that or did we get ripped off?

As I said any help anyone could give me would be awesome. I am really thinking we might have hired a shyster and need to know what I am really looking at here.

[scarey8]

HRV's will only dehumidifer in the winter months... anything outside of that would require and ERV

typically most homes do not require dehumidification via the ventilation system as the air conditioner looks after dehumidification during the summer season

if ducted correctly the HRV has the capacity to ventilate the house, and its proved its performance as you have said "for 3 months it kept the humidity down around 50-55%"

that also being said your hrv should be in low speed during the summer, ensure the control is not locked in high speed or the dehumidistat dial turned down too low, the hrv would be trying to dehumidify the house with humid outdoor air, therefore increasing your indoor RH

[Admin]

By Code, that HRV is good to use in a house with up to 5 bedrooms, regardless of the square footage.

It's likely the humidity was lower during the winter heating months, but has increased now that it's summer and more humid outside.

The Venmar user guide says,

Setting during the summer months:
During this period, unless being afflicted with breathing problems, using the Humidity Control is unnecessary. Set the slide switch to «OFF». (Do not exchange in day time; exchange at night time, if cool outside, or if it is not raining.)