Best case scenario you kill your furnace.
Can tankless water heater and furnace share vent.
Worst case scenario you kill your family.
This is because most homes have water heaters and furnace sharing the same exhaust vent.
It would be a potential fire hazard.
Yes venting tankless water heater with furnace is possible.
You furnace vent pipe is probably type b vent and not suitable for this use.
While there are high efficiency gas water heaters tank less units for one that utilize pvc for vents you will run into trouble trying to get the size correct for both.
Traditional gas tank water heater require venting through the roof.
Tankless heaters put out a lot of heat.
A high e furnace has separate venting which leaves the existing vent pipe to serve only the water heater.
Here are a few things your installer should consider for effective tankless water heater venting.
However the key here is to install the vent pipe in the size required by the water heater.
The tankless heater cannot share vent piping with any other appliance and it cannot use a masonry chimney flue for venting.
This unit is a condensing unit and requires a pvc vent so no you can t connect it to the common vent you describe.
Tankless water heaters can be vented in two ways.
The furnace is likely sized correctly with no room to add another appliance.
Typically they require stainless steel triple wall venting.
Special stainless steel pipe.
Facts about tankless water heater venting.
A direct vent system pulls in.
The furnace in the photos is a category i appliance a negative pressure draft vent appliance.
The difference is that a power vent water heater pulls in combustion air from the space around the appliance then uses a fan to propel the exhaust through the vent.
If you were to tie the vents together the exhaust from the tankless water heater would be pushed through the furnace and into your indoor space.
The vent pipe must be made of stainless steel designed for venting corrosive gases.
Always follow the manufacturer s installation instructions exactly.
Most homes have a shared vent serving both the furnace water heater when the furnace efficiency is up to 80 which is today s standard efficiency gas furnace.
Gas tankless water heaters don t have to use indoor air for combustion.
Tankless water heaters can vent through the roof or a side wall creating more flexibility and options for placement.
Tankless water heaters use fans to blow exhaust from the unit horizontally allowing vents to terminate on the side of a house.
Tankless water heater venting must be done correctly to ensure safe and efficient operation of the unit.
