Raypak B0507 Owner's Manual And Installation Instructions page 19

EXPANSION CONTROL VALVE
Local regulations may make it mandatory to install an expansion control valve (ECV) in the cold water line to the
water heating system. In other areas, an ECV is not required unless the saturation index is greater than + 0.4 (refer
"Water Supplies"
to on page 51). However, an ECV may be needed in a corrosive water area where there are
sufficient quantities of silica dissolved in the water.
The ECV must always be installed after the non return valve and be the last valve installed prior to the water heater
(refer to plumbing diagram shown above). A copper drain line must be run separately from the drain of the ECV.
RELIEF VALVE DRAIN
A copper drain line must be fitted to each relief valve (Pressure Relief and ECV if fitted) to carry the discharge clear
of the water heater. Connect the drain line to the relief valve using a disconnection union. The pipe work from the
relief valve to the drain should be as short as possible and fall all the way from the water heater with no restrictions.
It should have no more than three right angle bends in it. Use DN20 pipe.
The outlet of the drain line must be in such a position that flow out of the pipe can be easily seen (refer to
AS/NZS 3500.4) - but arranged so hot water discharge will not cause injury, damage or nuisance. The drain line
must discharge at an outlet or air break not more than 9 metres from the relief valve.
In locations where water pipes are prone to freezing, the drain line must be insulated and not exceed 300 mm in
length. In this instance, the drain line is to discharge into a tundish through an air gap of between 75 mm and
150 mm.
The drain lines from each relief valve can discharge into a common tundish. This also applies to the drain lines
from each water heater in multiple installations.
Warning: As the function of the temperature pressure relief valve on this water heater is to discharge high
temperature water under certain conditions, it is strongly recommended the pipe work downstream of the relief
valve be capable of carrying water exceeding 93C. Failure to observe this precaution may result in damage to pipe
work and property.
PLUMBING CONNECTIONS
Domestic Hot Water Applications
For domestic hot water applications, one or more storage tanks are required.

Install the storage tanks according to
supplied with the storage tanks and detailed on page

Install the water heaters according to
Diagrams"
shown on page 21.

Install the pump as detailed in the
Note: A disconnection union must always be provided at the cold water inlet and hot water outlet on the water
heater to allow for disconnection of the water heater.
Mechanical, Hydronic and Process Heating Applications
Refer to page 22.
Closed Loop Water Source Heat Pump Applications
Refer to page 23.
®
"Equa-flow
principles"
20)
®
"Equa-flow principles"
"Plumbing Diagrams"
shown on page 21.
19
CONNECTIONS – PLUMBING
(as described in the installation instructions
"Plumbing Diagrams"
and the
(detailed on page 20) and the
shown on page 21.
"Plumbing