ISSUE 2016 Rev 1 - Installation Manual
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RM Cylinders
the drain point. For electrical powered models where off peak tariffs are being used, then secondary circulation is not recommended.
All Indirect Coils
22mm primary coils of coil-in-coil design are fitted to all indirect models incorporating 22mm compression fittings for easy connection. These
coils are suitable for both open vented and sealed system applications up to a maximum of 6.0bar and must be positively pumped.
Ensure air release valves are used at high points such as the entry/exit points of the coil. Either connection may be used as the flow or return
without compromising performance.
Maximum operating temperature of primary coils under normal circumstances is 85° C.
Ensure corrosion inhibitor compatible with stainless steel coils is used in the primary circuit.
Connection to a Boiler
Gas, oil and electric powered boilers may be used but must be under effective thermostatic control and employ high limit control.
Uncontrolled heat sources must not be used.
The two port valve provided must be installed in the primary flow. The dual control/high limit thermostat provided fits onto the probe pocket
positioned just above the coil connection and wired back to the two port valve to create both temperature control and primary isolation should
the high temperature limit control be triggered -
See wiring diagrams.
Connection too Solar
For solar, connect to the solar coil allowing for air removal. The temperature sensor controlling the solar input connects into the probe pocket
directly above the solar coil connection using the cable grommet provided to ensure stable mounting. The single high limit thermostat installs
into the probe pocket at high level on the cylinder and wires back to the solar pump to prevent further input when triggered.
When connecting a twin coil cylinder to a boiler and solar thermal system the upper coil connects to the boiler and the lower to the solar
system.
Where a twin coil cylinder is being heated by two boilers, the upper coil should utilise the dual control/high limit thermostat as described in
Connection to a Boiler section. For connection to the lower coil you will require a further two port valve and a single control thermostat
(both
available from RM Cylinders)
to ensure a legal installation. The single control stat inserts into the probe pocket directly above the lower coil
and the single high limit stat into the probe pocket at upper level on the cylinder body. Wired together and back to the two port valve
connected into the primary flow this will provide temperature control and high temperature isolation of the primary heat source.
Wiring
A competent electrician in accordance with the latest I.E.E. wiring regulations should complete any electrical wiring required.
Typical Wiring – S Plan, 1 zone
Typical Wiring – S Plan, 2 zone
Typical Wiring – Y Plan
See Wiring Plans section (Pages 18 - 19).
Immersion Heater
As a requirement of the Building Regulations, the immersion heaters are fitted with a non-self setting thermal cut-out, in addition to the
normal control thermostat. The immersion heaters have a 1¾” BSP thread. They are of a low noise Incoloy construction and rated at 3kW at
240V. Replacement immersion heaters should be purchased via ourselves otherwise your guarantee may be affected.
The ‘O’ ring on the head of the immersion heater should be correctly positioned and lubricated before fitting. Screw in hand-tight until almost
sealed, and then gently tighten, as the ‘O’ rings will seal easily. The electrical supply to each immersion heater) must be fused at 13A via a
double pole isolating switch to BS 3456. The 3kW immersion heaters must be wired in 2.5mm heat resistant cable – failure to comply with
this can cause nuisance tripping and we will be unable to support your installation until this has been addressed.
Do not operate the immersion heaters until the unit is full of water. If any sterilization liquid is in the cylinder do not operate the immersion
heaters as this will cause premature failure.
In commercial or heavy duty installations, where constant usage and reheating is required, or where an external programmer designed for
immersion heaters is not present, Titanium immersion heaters must be fitted in order to comply with the warranty.
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