System Design - Viessmann VITOCELL 100-VH Technical Data Manual

Vitocell 100-VH/-BH Technical Data

System Design

Sensor well
The stainless steel sensor wells are to be used for control
sensors to ensure maximum operational safety. The top
sensor well is used for the DHW sensor connected to the
boiler control.
For solar heating systems, Viessmann recommends
placement of the DHW tank temperature sensor in the solar
collector return.
WARNING
To ensure optimum, safe operation, the stainless steel
well must be installed. The well diameter is large
enough to accommodate a wide variety of sensing
bulbs.
Always use spring clip to ensure proper contact of
capillary bulb against the stainless steel well for proper
sensing/heat transfer!
Heating water supply temperature over 230º F (110ºC).
These operating conditions require the installation of an
additional safety high limit into the DHW storage tank,
preventing the temperature from rising above 203ºF
(95ºC).
IMPORTANT
A domestic hot water tempering valve must be used.
Temperature and pressure relief valve
The heating contractor must install a temperature and
pressure relief valve (T&P relief valve) on each tank in a
method meeting code requirements. If local codes require
a different relief valve, substitute the manufacturer's
supplied valve. The tank is approved for 100 psig where a
CRN is required. Maximum operating pressure is 150 psig.
Maximum operating temperature is 210º F (99º C).
The T&P relief valve must be tested under ANSI Z21.22
Code for Relief Valves and Automatic Gas Shut-off Devices
for Hot Water Supply Systems.
Backflow preventers
Where backflow preventers are required, a domestic water
expansion tank installation must be installed in the cold
water inlet piping before the cold water enters the Vitocell.
For the backflow device, observe local plumbing codes and
regulations.
Electric heating element 4.5 kW
The optional screw-in electric heating element is used
in enameled solar and domestic water storage tanks as
auxiliary or emergency heating. It should be mounted in
a horizontal position by heating contractor.
WARNING
To avoid damage to the screw head and/or heating
element, do not operate the heating element without
a medium.
WARNING
Ensure the heating element ground wire is securely
connected to ground.
WARNING
Do not operate the heating element without a medium.
Damage to the heating element and screw head may
occur if operated without a medium.
System Design
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