Boiler Pressure Test; Low Water Cut-Off (Lwco) - Viessmann VITOROND 200 VD2A-125 Installation Instructions Manual

Connections
Safety Connections and Pressure Testing

Low Water Cut-Off (LWCO)

24
Vitorond 200, VD2A Series Installation
(continued)

Boiler pressure test

For the hydrostatic pressure test, please refer to page 21.
The boiler must be leak tested and hydrostatically
pressure tested with a maximum of 130 psig (896 kPa)
and a minimum of 127 psig (875 kPa) before being
connected to piping or an electrical power supply and
placed in operation.
1. Install supply and return headers complete with
pressure gage, temperature gage, air vent, low
water cut-off, boiler drain valve and bypass pump.
Pipe up to isolation valves. Close isolation valves.
2. Install temporary caps on the nipples for mounting
the pressure relief valve and expansion tank.
3. Connect hose to boiler drain valve and fill boiler
slowly until pressure gage indicates max. 130 psig
(896 kPa).
4. Maintain pressure for 30 minutes.
During time of pressure testing, do not leave boiler
unattended.
5. Inspect all push nipples and pipe connections with
flashlight for leaks.
Place a piece of paper under the cast iron block to
catch any minor leaks from the bottom push nipples.
6. After 30 minutes, release water pressure from
boiler by opening drain valve slowly, remove caps
and install pressure relief valve and expansion tank
immediately.
After boiler has passed pressure test, proceed with
installation.
If boiler is installed above radiation level, a low water
cut-off device of approved type (standard equipment)
must be installed in all instances. The approved low
water cut-off device must be installed by the mechanical
contractor where required by local codes.
Viessmann recommends the use of a LWCO in all
instances.