McDonald Engineers POWER flow 2000 Instructions Manual

UNVENTED HOT WATER SYSTEM

INSTRUCTIONS

PLEASE LEAVE WITH HOUSEHOLDER

IMPORTANT - Failure to install and maintain this system in

accordance with these instructions will invalidate the

manufacturer’s warranty

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McDONALD ENGINEERS

HOT WATER SYSTEMS

FLEMINGTON ROAD, QUEENSWAY INDUSTRIAL ESTATE, GLENROTHES FIFE KY7 5QF
Tel : [phone] Fax : [phone]

Email : [e-mail] Internet : www.mcdonald-engineers.com

IMPORTANT

Installation should only be carried out by a
‘competent operative’ i.e. the installer must
have attended a recognised course in
Unvented Hot Water Systems or received
appropriate training in their apprenticeship.
All registered operatives should carry an
Identification Card issued by the Institute of
Unvented Hot Water Systems or SNIPEF
(Scottish and Northern Ireland Plumbing
Employers’ Federation), the Construction
Industry Training Board or the Institute of
Plumbers.

The unit should be
handled with care in order to avoid
damage to valves. It should be stored
upright in its box in a dry place.

Full weights are available at the back of
this booklet. The installation area should
be able to cope with this weight, incoming
pipes and discharge pipe. Position the
unit to suit the installation.

All connections are to the front to enable
ease of access. Ensure suitable space is
left for access for repair and/or
replacement of valves etc.

In areas with hard water we would
recommend restricting the temperature
and performing de-scaling procedures as
required.

All the following instructions must be
carried out: -

1. Installers should ensure incoming
mains pressure
that local authority approval for
installation of Unvented Systems is
granted. Ensure adequate flowrate is
available.

is less than 12Bar and

2. Excessive use of flux
unit and especially the valves and
expansion vessel. Avoid over-use and
ensure the system is fully flushed of
any debris or flux before connection.

3. Incoming mains to arrive in a
minimum of 22mm copper pipe which
is to be fitted to the P
Reducing Valve Set at 2.1 Bar (A - see
Page 4) which includes a serviceable
Strainer. We would strongly
recommend this valve is fitted where
the mains enters the property, but it
can go wherever is most suitable for
the installation, between the mains
stopcock and the cylinder.

We recommend fitting a Tee between
the Pressure Reducing V
the Check Valve (A2) to provide a
BALANCED COLD OUTLET for all
cold taps, preventing cross-flow and

also giving potable water throughout
the house. Outdoor taps for hoses

should be taken before the Pressure
Reducing V

The Check V

4.
at the Cold Feed (C). No isolating
valve may be fitted between the check
valve and the storage cylinder.

5. The T
Valve (D) set at 90°c and 4.5 Bar, and
the Expansion Relief V

3.5 Bar, are factory fitted and
connected to the Tundish (E). NB -
the relief valves are only to be used
for relief discharge purposes.

No valves should be fitted between
the relief valves and the cylinder.

1

alve.

alve (A2) is factory fitted

emperature & Pressure Relief

can damage the

ressure

alve (B) set at

alve (A) and

6. The Tundish (E), which shows visible

discharge from the Relief Valves, is to
be in a prominent, visible and safe
position away from any electrical
devices (likewise with the drain
connection) and within 500mm of the

Temperature & Pressure Relief Valve

(D). Pipework from the Tundish (E)
must initially be vertical for a minimum
of 300mm where possible and then
have a continuous fall in excess of 1
in 200. Pipework away from the
Tundish (E) should be in a minimum of
22mm, of material suitable for
temperatures of 95°C and have a
resistance to flow of water not greater
than that of a straight pipe of 9 metres
(each bend or elbow is equal to 0.8
metre of resistance). See BBA
Information. Sheet No 33:1989 for
further details - available from the
manufacturer

. Also note page 9 of

these instructions.

7. The Expansion V

essel (F) charged at

2.1 Bar, should either be fitted directly
to connection (M) on the cylinder

, or if
space dictates, securely to the wall
with the optional remote fixing kit and
the hose fitted between the vessel and
connection (M).

8. Connect the 3kW 11” 240V Immersion
Heater/s BSEN 60335/2/73 (with
manual re-set cut out at 80°C) to the
power supply and earth them in
accordance with the current IEE wiring
regulations. The fuse rating should be
13 Amps. Do not at any time fit

Immersion Heaters without a thermal
cut-out.

9. On Indirect Units

to the cylinder, the supplied T

where a Coil is fitted

wo Port
Motorised Zone Valve and Dual
Thermostat Controller (J) must be

fitted in accordance with the
instruction details supplied with them
for the appropriate installation.

N.B. Indirects, are suitable for oil,
gas and electric fired boilers on a
pumped, gravity or sealed system.
(W

e would however recommend
28mm Coil connections with a 28mm
Zone Valve on gravity systems).
Maximum working pressure of the
coil is 3.5 Bar. All electrical wiring to

thermostats, zone valve and
immersion heaters must be earthed
and to current IEE Wiring Regulations.
The fuse should generally be 3 Amps
but refer to appliance instructions to
confirm this.

10.

The Secondar

y Return (L) if supplied,

should be plugged if not required. If
the Secondary System pipe-work is
greater than 15% of the unit capacity,
a larger Expansion Vessel may need
to be fitted - contact McDonald
Engineers.

11. Immersion Heaters

(H) and the Dual

Aquastat Controller (J) supplied with
the Indirect units should be set to no
greater than 60°C and the internal
High Limit Thermostats are factory set
no higher than 85°C. Always check

this before switching on power

Please see the checklist on page 4
to ensure all controls are present
and correct.

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ONCE ALL THE PRECEDING INSTRUCTIONS HAVE BEEN
FOLLOWED, COMMISSION THE SYSTEM.

IMPORTANT

COMMISSIONING - These instructions
must be followed.

After following the instructions on pages
1 & 2 proceed as follows: -

1. Close the Drain-cock (I) at base of

cylinder.

2.

Open a Hot Tap.

3. Fully open the Cold Mains Stopcock
and fill Cylinder until water appears at
the Hot Tap.

4. Close the Hot Tap and attend each hot

water outlet in turn and ensure water
flow is obtained at each.

ENSURE THAT ALL FITTINGS AND
PIPEWORK ARE W

All factory fitted valves etc. are fitted
using a thread sealant.
If this seal is broken it should be
re-sealed using a suitable sealant.

ATERTIGHT.

5. Check the control thermostats on the

Immersion Heater/s (H) and the Dual
Thermostat (J) are set no higher than

6

0°C and that the High Limit
Thermostats are set to no higher than
85°C.

6. Ensure there is no discharge from the
Relief Valves (B and D).

7. Switch on water heating system and
check operation of the system.

IT IS EXTREMELY IMPORTANT TO
FOLL

OW ALL THE INSTRUCTIONS
PREVIOUSLY MENTIONED, AS FAILURE
TO DO SO COULD BE DANGEROUS OR
LEAD TO THE SYSTEM WORKING
INEFFICIENTLY.

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