Rinnai i-Series vs Viessmann Vitodens 222-F: Boiler Comparison

Need a licensed gas fitter for your gas boiler? Call CANRO at (604) 359-1081 — residential natural-gas heating and hot water across Metro Vancouver since 1999.

This is a format decision, not just a brand decision

Most boiler comparisons pit two similar wall-hung units against each other. This one is different, because the Vitodens 222-F is a floor-standing condensing boiler with integrated hot water storage. In other words, the boiler and a hot-water tank live together in one floor-standing cabinet. The i-Series is a condensing wall-hung boiler that comes as a solo (heat-only) unit or as a combi that makes hot water on demand.

So the real question is which way you want your hot water delivered, and how much floor and wall space you can give up. We describe both boilers by type only and leave out outputs, tank capacities and efficiency figures, since those belong to the manufacturers' documents for the exact model you choose.

Stored hot water versus on-demand hot water

Neither approach is universally superior. A big family that showers in a cluster in the morning will appreciate stored water; a couple in a small house may never notice the difference and will value the reclaimed space.

Floor space, weight and access

A floor-standing boiler with built-in storage is a substantial piece of equipment. It needs a proper footprint, a firm level base and a route from the door to the mechanical room. In an older Vancouver house with a narrow basement stair or a low doorway, getting it in is a real planning question, and a technician looks at that during the assessment. A wall-hung boiler is lighter and easier to carry down a stair, though it needs a wall that can support it and clear space in front.

The flip side is tidiness. Putting the boiler and the storage together in one cabinet can reduce the number of separate components on the wall, the piping between them and the wiring to coordinate them. Homeowners who dislike a cluster of parts on a basement wall sometimes find that appealing.

How the piping and controls differ

An integrated design means the manufacturer has already arranged how the boiler and its storage work together, which can simplify installation. A wall-hung boiler with a separate indirect tank leaves the arrangement to the installer, which gives flexibility to size the tank to your household but adds more field-made connections. Either can be done well. In our experience the quality of the piping, air removal and controls matters more than whether the tank is inside the cabinet or beside it.

Radiators, radiant floors and condensing

Both boilers are condensing, so both do their best work when the water returning from the house is cool enough to condense exhaust vapour. Radiant floors and baseboard help; older radiators sized for hot water may reduce condensing time in the coldest weather, which is a system design consideration and not a defect. Outdoor reset and thoughtful control settings apply equally to both.

Venting and condensate

Both generally vent through sealed pipe and drain condensate through a trapped line. The manufacturers' installation manuals set the approved vent materials, lengths and clearances. A floor-standing boiler sits low, so the condensate drain may be easier to reach than for a wall-hung unit mounted higher up, though the vent still has to reach a safe exterior termination. If the old boiler shared a chimney with a gas water heater and that water heater stays, its venting is reviewed as its own safety item.

Servicing a boiler with built-in storage

A cabinet that houses both boiler and storage tank puts more into one place. That is convenient, but when service is needed the technician works within one integrated unit. A wall-hung boiler with a separate tank lets each part be serviced or replaced independently. Ask any installer what happens if the tank side needs work later, and how easy the manufacturer's parts support is to reach in British Columbia. CANRO is not an authorized or factory dealer for Rinnai or Viessmann; we are a licensed gas contractor that installs and services hydronic boilers, and we advise on the format that suits the house.

Which fits which home

• A busy family home with a dedicated mechanical room and floor space: an all-in-one floor-standing boiler with storage is worth a serious look.
• A smaller house, a laneway suite or a compact mechanical closet: a wall-hung i-Series, particularly the combi version, is often easier to fit.
• A home with a difficult access route to the basement: the lighter wall-hung unit is easier to carry in.
• A home replacing an older floor-standing boiler in the same spot: a floor-standing replacement may reuse existing connections.
• A home with radiant floors: both work, provided the mixing and controls are designed properly.

We do not declare a winner. The house decides.

Replacing an old boiler and water heater together

Many Lower Mainland homes have an older heating boiler in one corner of the basement and a separate gas water heater in another. When both are near the end of their lives, an integrated floor-standing unit with built-in storage looks attractive because it can consolidate two aging appliances into one cabinet and one venting arrangement. That can free a second vent, a second gas connection and a chunk of floor space.

It is not always the right move. If the water heater is still sound, replacing it early is unnecessary, and a wall-hung boiler that leaves the existing water heater alone can be the more economical route. We look at the age and condition of both appliances, and at the state of the chimney if they share one, before suggesting a consolidated setup. If the boiler leaves a shared chimney, the remaining appliance's venting must be reviewed as its own safety matter.

Living with the system day to day

Homeowners rarely think about boilers until something changes, so it helps to know what normal looks like. With stored hot water, a tank that has been run down by heavy use takes a while to recover before the next long shower. With a combi, the wait for hot water at a distant tap is set by the length of the pipe run, and the unit's response to a call for hot water. Neither behaviour is a fault. What matters is that you know what to expect and that your installer explains it, so that a genuine change stands out when it happens.

Sizing and what we do

Whichever format you choose, sizing comes from a room-by-room heat-loss calculation, with hot-water demand assessed separately. We then quote in writing, arrange the gas permit through Technical Safety BC and install to the manufacturer's manual. CANRO's gas licence is LGA0043870 and its boiler licence is LBP0046450. This comparison includes no pricing; the CANRO office gives a written quote after a short assessment.

Frequently asked questions