Page 15 - Introduction

Don’t leave it to chance, get it right first time, if you think it’s expensive to hire a
professional wait to you count the costs of hiring a amateur.
Contact us on Skype/Phone: +44 (0) 161 8188974, Mobile: +44 (0) 7488298027,
email: paul.mcmullan@subtechengineers.com

Pressurisation Units & Expansion Vessels

In the UK as our heating and chilled water systems are normally sealed pressurisation unit are
used to re-fill the system and maintain a minimum pressure to prevent air entering the system, the
expansion vesels are there to absorbed the volume of expaned water as the system is heated.

Most UK based pump manufacturer have there own pressurisation
units and as per there booster sets they all claim theres is the best,
There not really that much to them a small pump cable of delivering
the pressure higher than what you need a small break tank (AB
airgap) and a means of control, The starter level is the open base
pack unit switched by a pressure switch and the down stream
pressure controled via a pressure regulating valve. (cheap &
cheerful)

Of course there the two pump (duty/standby) unit,digitally controlled,
mounted in an eye pleasing cabinet.(but it does the same thing),
like the cold water booster sets it down to personal preferance.

There are even wall monted units if you
need the floor space.

There are numerus makes and sizes of expension vessels (pressure vessels), for small pipe
mounted unit to large vertical standing units ranging in sizes from 3 liter to 5000 liter with pressure
ratings from 10 bar to 25 bar, you should use WRAS approved and CEmarked vessels, suitable for
tempretures you are working at.
SYSTEM CONTENT

SYSTEM STATIC
Care must be taken when sizing the expansion vessel
to ensure you have sufficent volume, to size the vessel FLOW TEMP.
you need to know the following information: MAX. WORKING
PRESSURE
BOILER RATING

That’s what we do, we can take help you with your design, selecting the right pump set for the right