MVHR vs Kitchen Exhaust

[mike2016]

Hi,

I read a new article in treehugger about a test of household air quality vs kitchen exhaust in a Passive House setting. 

https://www.treehugger.com/kitchen-design/exhaustive-new-study-looks-kitchen-exhaust-and-household-air-quality.html

The test was with Induction. Just wondering if anyone here had any thoughts? BBQ outside only? 

How would kitchen air spread to bedrooms - kitchens would be extracting and bedrooms would be supplying so the flow should be the other way, shouldn't it? 

[dogman]

Fitting an external exhaust from the cooker hood is the one thing i wish i had fitted. Even if i had put in the duct but not actually breached the air tight envelope would have been the best option so that i had the option to duct it outside.

 

Smell so far is not the issue its the heat in the summer 

[Weebles]

Just starting the MVHR install so thinking about ducting and punching holes through the thermal envelope. I recall @dogmanthat you have a separate oven and hob. So are you talking about the extractor above the hob?  Are you suggesting an external venting extractor unit (rather than recirculating) for heat reasons?

 

And because i know nothing about these things, how does an extract work for a stand alone oven? Do you even need one?

[joe90]

16 hours ago, dogman said:

Smell so far is not the issue its the heat in the summer 

 

We have a window either side of our cooker and if the heat is a bit much we open them creating a cross draught.

[dogman]

@Weebles we have two electric ovens (neff hide and slide) and a 5 burner LPG hob. Above the hob is a luxair glass extractor fitted with twin carbon filters set to recirculate

 

The oven units  have vents at the back but the Neff seems to vent through a vent above the doors at the front. As they are next to the hob extractor the heat would be drawn into the extractor

 

I have found that the house stays cool if you do not introduce heat including from outside so i do not really want to open doors or windows. However that is my only choice as an MVHR even on boost cannot remove the heat from cooking( we have fitted two ducts to the MVHR extract in the kitchen that copes well with smells from cooking.

 

I wish i had put a duct from the luxair extractor to the outside wall so i had the option to vent the cooker hood outside( i know that the negative pressure caused by the removal of 980m³/hr at full belt  would require us opening a window but at least that could be at the cool side of the house.

 

I would have not cut the hole until i had passed the air test and fitted an air valve to shut it off if needed.