dryer & bathroom venting with HRV?

[elecengr]

I'm having a small home built to be relatively energy-efficient: with HRV.
The builder in rural area is new to the ideas but amenable. I find conflicting info on whether HRV can vent dryer, bathroom. And am I way off in planning to use an airtight stove for much of heating? Any suggestions for sources of info?

[Carnak]

Do not vent the dryer through the HRV.

You can draw exhausts from the bathroom.

[teddy bear]

Climate and heat source? Size of home and number of people?

[engineerguy]

Take the HRV air from the bathrooms. Put the HRV supply air into the heating ductwork, or as far from the bathrooms as you can. If you like long hot showers, you may want to add a pushbutton in the bathroom to switch the HRV to high speed.

[elecengr]

Thanks for the help, team. I'll install a dryer vent to outside, and rely on the HRV to remove shower/bath moisture. CO and smoke detectors near the airtight stove will alert us if there's any backdraft problem with depressurization due to the dryer.

[iaq_matters]

Originally posted by elecengr
Thanks for the help, team. I'll install a dryer vent to outside, and rely on the HRV to remove shower/bath moisture. CO and smoke detectors near the airtight stove will alert us if there's any backdraft problem with depressurization due to the dryer.

Definitely install an override timer in each room where you are exhausting stale air – this will allow you to bump the system to high speed ventilation mode for bathroom use.

Some people prefer to install an Inline Fan or ceiling exhaust fan (separately ducted to the outside) in addition to the HRV exhaust inlet for the main bathroom,; especially if there is a Jacuzzi tub and such. This fan can be used as an extra boost when required, i.e.…weekday mornings during high shower use, Jacuzzi bath tub, mother in law after Thanksgiving dinner etc…

Also – be sure to vent your range hood to outside, and don’t get caught up in the 500CFM and bigger Range Hoods hype. It’s simply not required for most homes.

Last point – make sure your HRV gets balanced – number one most important commissioning step that quite often gets over looked. When properly balanced your HRV will run at its rated efficiencies and won’t freeze up in the winter.

[teddy bear]

With the wood burner stove, make-up air ventilation makes more sense. 50-75 cfm of make-up air is all the fresh air you need. This will maintain a slightly positive pressure which is necessary with a stove. A smoldering wood burner in slight negative home will leak smoke when reloading. This a tremendout compromise for IAQ. Like smoking everyday. The clothes drier exhaust 100 cfm leaving your home to provide 25 cfm. HRVs are balance devices providing no make-up air. A negative is that a HRV will save 1/2 cord of wood a year. TB

[engineerguy]

Get a woodburner with provision for combustion air ducted directly from outside. Then it has sealed combustion when the stove door is closed and the dryer cannot suck smoke into the house (except when opening the door). CO and smoke detectors are always good to have.

[tonys]

I've never seen a CO detector work.

...could be the cheap parts from China.