# Bathroom fan/ Furnace interlock



## Majewski (Jan 8, 2016)

Have you seen this yet? http://www.electriciantalk.com/f31/parallel-fan-ciruit-46058/


----------



## Missouri Bound (Aug 30, 2009)

mike9666 said:


> interlock the primary exhaust with the furnace.


To what end?
Is the goal to stop the furnace when the fan activates or not allow the fan when the furnace blower is running?
Either way it sounds like a terrible idea. Whacky Canuks.


----------



## daveEM (Nov 18, 2012)

@Majewski pointed you to a good thread. In one of my posts there (#23) I say...

_The relay i use and wiring diagram can be found here..._
http://www.hoyme.com/index.php?option=com_content&view=article&id=166:adp-1101-05a-installation-instructions&catid=64:adp-installation-instructions&Itemid=188


----------



## Majewski (Jan 8, 2016)

I found a few diagrams and articles from Alberta online but I liked that thread best and it was still in house. Figured he'd have a better time asking questions about a previous thread.


----------



## Vintage Sounds (Oct 23, 2009)

Missouri Bound said:


> To what end?
> Is the goal to stop the furnace when the fan activates or not allow the fan when the furnace blower is running?
> Either way it sounds like a terrible idea. Whacky Canuks.


The point is to have a manually operable ventilation switch. You turn it on, it starts a bathroom exhaust fan at the top of the house and the furnace blower at the same time. While the ventilation switch is on, you can't turn the bathroom fan off by using the regular exhaust fan switch in the bathroom. It's actually pretty useful for getting fresh air into the house. Most houses in Alberta don't have central A/C because of the short summer.


----------



## Missouri Bound (Aug 30, 2009)

Vintage Sounds said:


> It's actually pretty useful for getting fresh air into the house.


How? Furnaces do not heat fresh air, they heat the air in the house.:no:
Unless there is a way to exchange air all the exhaust fan does is suck air in through cracks. I can see some sort of make up air device working but that is rare in residential situations.


----------



## 99cents (Aug 20, 2012)

A newer home with proper vapour barrier will have a fresh air intake to the furnace.


----------



## MechanicalDVR (Dec 29, 2007)

99cents said:


> A newer home with proper vapour barrier will have a fresh air intake to the furnace.


I'd say at best you can say "most" newer homes with proper insulation and a vapor barrier have fresh air inlet or an ERV (energy recovery ventilator) piped into the return air to the furnace.


----------

