Rinnai HD49kWi Continuous Flow Water Heaters Installation Guide

: June 5, 2024
: Rinnai

Table of Contents

Rinnai HD49kWi Continuous Flow Water Heaters
Product Information
Product Usage Instructions
FAQs
Flueing options
Flueing guidelines
UV roof protectors
Installation
MORE INFO
CONTACT
References
Read User Manual Online (PDF format)
Download This Manual (PDF format)

Rinnai HD49kWi Continuous Flow Water Heaters

Product Information

Specifications
- Compatible with Rinnai INFINITY models: HD49kWi REU-VCM2837FFC-ZK, A28i REU-VCM2837FF-ZK
- Material: Stainless steel inner pipe, thermoplastic outer pipe
- Gas Type: Natural Gas or Universal LPG
- Manufacturer’s installation instructions Compliance: AS/NZS 3000, AS/NZS 3500, AS/NZS 5601.1, G12/AS1

Product Usage Instructions

Flueing Options
- Direct Flueing: For installations through an external wall with the direct flue kit FFSSKIT. Maximum wall thickness approximately 460 mm.
- Horizontal Extension Flueing: Use direct flue kit FFSSKIT with additional pipe lengths. Slope horizontal flues back towards the water heater at a 20 mm fall per metre for condensate drainage.
- Vertical Straight Flueing: Install vertically through the roof.
- Combination Flueing: Use a combination of horizontal and vertical flueing.
Flueing Guidelines
- Multiple Flues: Maintain minimum distances as indicated in the guide. Terminations should be at the same height.
- Flue Support: Ensure the flue is supported independently using suitable clips or brackets as per AS/NZS 5601. Standoff brackets are provided with FFSSROOFCOWL and FFSSPIPE1000.
- Flue Length: Refer to the chart for maximum flue length and number of bends allowed.
- Vertical Terminations: Provide adequate clearance from the building for proper combustion product dispersal. Vertical flue cowl should have a 500 mm clearance from any part of the building, including roofs. Maintain adequate fresh air flow around the flue cowl post-installation.

FAQs

Q: Can I use the fleeing components for other Rinnai INFINITY models not listed?
- A: The flueing components outlined in this guide are specifically designed for the mentioned models. For other models, refer to their respective installation manuals or contact Rinnai for guidance.
Q: What should I do if I encounter condensation in the flue system?
- A: If condensation occurs, ensure proper slope for condensate drainage in horizontal flues and check for any blockages or obstructions in the system. Contact a professional if issues persist.

Please note

The installation and flue component images throughout this guide refer to our current range of internal models, the HD49kWi and A28i.
Please adapt this information as necessary if you are referencing this document for discontinued internal models.

Flueing options

The flueing for internal water heaters is a coaxial design.
It has a stainless steel inner pipe to discharge products of combustion and a thermoplastic outer pipe for air supply to the appliance.
Each Rinnai INFINITY water heater is flued individually, refer flueing options below.
1. Direct fleeing
- For direct flue installations through an external wall using the direct flue kit FFSSKIT— the maximum wall thickness is approximately 460 mm.
1. Horizontal extension fleeing
- For flue installations through an external wall use the direct flue kit FFSSKIT and additional lengths of pipe.
- Slope horizontal flues back towards the water heater at a 20 mm fall per metre to drain condensate.
1. Vertical straight fleeing
- Installations where the internal unit is flued vertically through the roof.
1. Combination fleeing
- Installations using a combination of horizontal and vertical fluting.

Flueing guidelines

Flue gases can reach temperatures up to 200 °C. The flue terminal is to terminate in a location so as not to cause a nuisance, by AS/NZS 5601.

Multiple flues

Ensure minimum distances, as shown below are maintained.
Each terminal is to be terminated at the same height, refer images below—please note these images show our older style terminals, which have since been updated.

Flue support

Ensure the flue is supported independently of the appliance use of suitable clips or brackets in accordance with AS/NZS 5601. Appropriate standoff brackets are supplied with each FFSSROOFCOWL and FFSSPIPE1000.

Flue length

The chart below highlights the maximum flue length and number of bends.

Vertical terminations

To ensure products of combustion are cleared, adequate clearance from the building is required.
The vertical flue cowl should have a 500 mm clearance from any part of the building.
This also applies to steeped and pitched roofs, where the flue cowl should be 500 mm clear of the ridge line.
An adequate flow of fresh air must exist around the flue cowl following installation.
Minimum clearances are shown in AS/NZS 5601.1.

Flue spigots on top of the unit

Rinnai INFINITY internal units manufactured from approximately 2008 onwards have a female flue spigot on top of the unit. This differs from older internal models which have a male flue spigot.
This is relevant if you are trying to fit a new internal unit into an old fling. In these instances, we recommend, due to the age of the flueing, that the flueing be changed as well.
We no longer have male flue spigots that can be retrofitted to our current models.

Appliance spigot centres

The wall mounting brackets are adjustable by 43 mm, the minimum setting is 10 mm.

Adjusting the mounting bracket also adjusts the spigot centre. The adjustment range is:

HD49kWi / A28i 105.3~148.3 mm

Condensate

A condensate trap kit (FFSSCOND) is required for flue lengths over 1.5 m. If the flueing is less than 1.5 m, the flue spigot on top of the unit is capped using the drain cap tube supplied with the unit.
The drain cap is only removed if the condensate kit is connected.
The condensate trap collects any condensate from the flue and prevents condensate from entering the water heater and causing damage.
Condensate is a by-product of gas combustion and is mildly acidic. For this reason, copper tubes and fittings must not be used as they will corrode. Instead, Rinnai recommends plastic pipe and fittings such as UPVC or PE.

UV roof protectors

The roof cowl comes with three black UV pipe sections for covering and protecting the white pipe from UV damage.
To install, click together and if required cut to length, refer image below. If any remaining white pipe is exposed to UV, this should be painted with a suitable UV-resistant coating.

Important

When installing the UV protectors the protector must sit outside the deck tile, not inside.
Weather tightness will be an issue if the protector is installed inside the deck tile.

Cutting to size

Pipes overlap by approximately 37 mm. Once joined the effective length is reduced by 37 mm. This needs to be factored in when cutting to size. Add two x 37 mm to extension pipe X.
The inner pipe must always extend 10 mm beyond the outer pipe in the male end of the flue.
Always cut the male end of the flue and not the female end. Deburr sharp edges as this could damage the gasket resulting in a system that is no longer air-tight.

Direct fleeing using the FFSSKIT

For installations where the Rinnai INFINITY is mounted directly on the inside of an external wall with a maximum wall thickness of approximately 460 mm. Horizontal flues must slope 20 mm per metre back towards the water heater.

The FFSSKIT contains:

90 °bend
Horizontal flue terminal
Internal white rubber wall trim
External grey rubber wall trim

Installation

Mount the water heater in an appropriate location.
Using the dimensions provided, mark a point along the appliance centreline 150 mm from the top of the water heater. This mark forms the centre for the 140 mm diameter wall penetration.
When installing the FFSSKIT directly backwards from the appliance, set the water heater mounting brackets to the minimum (10 mm).
Make a 140 mm wall penetration for the flue. Ensure that the flue spigot of the water heater is covered while working to avoid debris entering the flue connection of the appliance.
Measure the required length for the horizontal terminal to penetrate the wall and allow an extra 67 mm protrusion from the inside wall surface.
Fit the external wall seal to the terminal pipe. Pass the male end of the terminal pipe through the penetration point and weatherproof the penetration. Fit the internal wall seal.
Connect the terminal pipe to the bend, ensuring the components are pushed ‘fully home’. Secure the PVC joints of the bend to the terminal pipe with three self-tapping screws (not supplied).

Extended horizontal flue

The extended horizontal flue option can be used when the water heater is mounted against an internal wall and the flueing needs to be extended horizontally for a longer distance to exit an external wall.
Use the FFSSKIT as a starting point and customise with flue pipe. The total length can be up to 13 m.
Remember to allow for a condensate connection, you will need a condensate trap kit (FFSSCOND).

Vertical and combination fleeing

If starting horizontally and finishing horizontally, use the FFSSKIT as a starting point and customise. If starting horizontally and ending vertically or vice versa, individual flue components will need to be ordered. Flueing must start with a FFSSBEND90 or FFSSPIPE1000. The distance of the centreline of the appliance flue spigot from the wall is variable, refer to p.6.Take this into account when creating access holes through floors and ceilings for flue pipe components.

Mount the water heater in an appropriate location.
Set a plumb bob from the centre of the heater flue outlet to the ceiling marking position. Cut a 140 mm hole in the plasterboard (or a suitable oval for pitched applications). Repeat this step for the underside of the roof.
Install the UV protectors to the vertical terminal.
Calculate the required number and combination of FFSSPIPE1000 lengths and cut to size as required.
Install deck tile roof seal (not supplied).
Ensure the flue is fully supported independently of the appliance, by the use of suitable clips or brackets, following AS/NZS 5601. Appropriate standoff brackets are supplied with each FFSSROOFCOWL and FFSSPIPE1000 component.
All PVC joints must be secured with suitable self tapping screws.
Install suitable condensate drainage, refer to p.6.

INFINITY stainless steel flue components

All the major flue components are constructed of a PVC outer and a stainless steel inner. These have zero clearance to combustibles. All dimensions are in mm.

FFSSBEND90: 90° bend

FFSSBEND45: 45° bends, sold as a pair

FFSSPIPE1000: Flue pipe, can be cut to size, and includes a Munzing ring to support the flue

FFSSCOND: Condensate trap kit

FFSSROOFCOWL: Roof cowl for vertical installations, can be cut to size

Includes three black injection UV roof components (1 collar adapter, 2 roof protectors), for covering and protecting the white flue pipe from UV damage. The roof protector can also be ordered as a spare (12693, one protector). The Kit also includes a flue pipe clamp to support the flue.

FFSSKIT: Direct flue kit for horizontal installations, can be cut to size

MORE INFO

The fleeing components outlined in this guide are suitable for the following internal Rinnai INFINITY models:

Current models

HD49kWi REU-VCM2837FFC-ZK
A28i REU-VCM2837FF-ZK

INFINITY HD49kWi and A28i continuous flow water heaters Stainless steel flue installation guide

Important

Rinnai INFINITY gas water heater fleeing shall be installed by:

Manufacturer’s installation instructions
Current AS/NZS 3000, AS/NZS 3500, AS/NZS 5601.1 and G12/AS1

For use with Natural Gas or Universal LPG as indicated on the appliance. Appliances must be installed, commissioned, serviced, and removed by an authorised person, being in New Zealand a licensed gasfitter.

Warning

Improper installation, adjustment, alteration, service and maintenance can cause property damage, personal injury or loss of life. For more information about buying, using, and servicing of Rinnaiappliances call: 0800 RINNAI (0800 746 624).