Baxi PRIME HT 240 User manual

Wall-mounted condensing boilers
Installerʼs and Userʼs Instructions
BAXI S.p.A. is a leading European manufacturer of central heating and domestic hot water appliances (wall mounted gas
boilers, floor standing boilers, electric water heaters) and has been certified by CSQ as conforming to UNI EN ISO 9001.
This certification confirms that the Quality System of
BAXI S.p.A. in Bassano del Grappa, where this boiler was manufactured,
satisfies the strict UNI EN ISO 9001 standard covering all aspects of company organisation, manufacturing and distribution.
UNI EN ISO 9001
CERTIFICAZIONE DEI SISTEMI
QUALITA' DELLE AZIENDE
PRIME HT
0085
GB

2
INSTRUCTIONS FOR THE USER
Dear Customer,
We are sure your new boiler will comply with all your require-
ments.
Purchasing one of the BAXI products satisfies your expecta-
tions: good functioning, simplicity and ease of use.
Do not dispose of this booklet without reading it: you can find
here some very useful information, which will help you to run
your boiler correctly and efficiently
.
Do not leave any parts of the packaging (plastic bags, polystyrene, etc.) within children’s
reach as they are a potential source of danger.
BAXI boilers bear the CE mark in compliance with the basic requirements as laid down
in the following Directives:
- Gas Directive 90/396/CEE
- Performance Directive 92/42/CEE
- Electromagnetic Compatibility Directive 89/336/CEE
- Low Voltage Directive 73/23/CEE

3
INSTRUCTIONS FOR THE USER
9. General information 9
10. Instructions prior to installation 9
11. Boiler installation 10
12. Boiler size 10
13. Fittings present in the packaging 11
14. Installation of flue and air ducts 11
15. Connecting the mains supply 15
16. Changing gas type 22
17. Displaying electronic control card parameters on the boiler display (“INFO” mode) 25
18. Control and operation devices 27
19. Positioning of the ignition and flame sensing electrode 28
20. Check of combustion parameters 28
21. Activating the flue-sweeper function 29
22. Output / pump head performances 29
23. How to disassemble the DHW heat exchanger 30
24. Cleaning the cold water filter 30
25. Annual service 30
26. Using the Siemens QAA73 temperature regulator to program boiler parameters 31
27. Boiler schematic 33-34
28. Illustrated wiring diagram 35-36
29. Technical data 40
1. Instructions prior to installation 4
2. Instructions prior to commissioning 5
3. Commissioning of the boiler 5
4. Filling the boiler 7
5. Switching the boiler off 8
6. Prolonged standstill of the system. Frost protection 8
7. Gas change 8
8. Servicing instructions 8
CONTENTS
INSTRUCTIONS PERTAINING TO THE USER
INSTRUCTIONS PERTAINING TO THE INSTALLER

4
INSTRUCTIONS FOR THE USER
This boiler is designed to heat water at a lower than boiling temperature at atmospheric pressure. The boiler must be
connected to a central heating system and to a domestic hot water supply system in compliance with its performances
and output power.
Have the boiler installed by a Qualified Service Engineer and ensure the following operations are accomplished:
This boiler is designed to heat water at a lower than boiling temperature at atmospheric pressure. The boiler
must be connected to a central heating system and to a domestic hot water supply system in compliance with
its performances and output power.
Have the boiler installed by a Qualified Service Engineer and ensure the following operations are accom-
plished:
a) careful checking that the boiler is fit for operation with the type of gas available. For more details see the
notice on the packaging and the label on the appliance itself.
b) careful checking that the flue terminal draft is appropriate; that the terminal is not obstructed and that no
other appliance exhaust gases are expelled through the same flue duct, unless the flue is especially de-
signed to collect the exhaust gas coming from more than one appliance, in conformity with the laws and
regulations in force.
c) careful checking that, in case the flue has been connected to pre-existing flue ducts, thorough cleaning
has been carried out in that residual combustion products may come off during operation of the boiler and
obstruct the flue duct.
d) to ensure correct operation of the appliance and avoid invalidating the guarantee, observe the following
precautions:
1. Hot water circuit:
1.1. If the water hardness is greater than 20 °F (1 °F = 10 mg calcium carbonate per litre of water) a
polyphosphate or comparable treatment system responding to current regulations.
1.2. Domestic Hot Water circuit must be thoroughly flushed after the installation of the appliance and before
its use.
2. Heating circuit
2.1. new system
Before proceeding with installation of the boiler, the system must be cleaned and flushed out thoroughly
to eliminate residual thread-cutting swarf, solder and solvents if any, using suitable proprietary
products.
To avoid damaging metal, plastic and rubber parts, use only neutral cleaners, i.e. non-acid and non
alkaline. The recommended products for cleaning are:
SENTINEL X300 or X400 and FERNOX heating circuit restore. To use this product proceeding strictly
in accordance with the maker’s directions.
2.2. existing system
Before proceeding with installation of the boiler, the system must be cleaned and flushed out to remove
sludge and contaminants, using suitable proprietary products as described in section 2.1.
To avoid damaging metal, plastic and rubber parts, use only neutral cleaners, i.e. non-acid and non-
alkaline such as SENTINEL X100 and FERNOX heating circuit protective. To use this product proceeding
strictly in accordance with the maker’s directions.
Remember that the presence of foreign matter in the heating system can adversely affect the operation
of the boiler (e.g. overheating and noisy operation of the heat exchanger).
Failure to observe the above will render the guarantee null and void.
1. INSTRUCTIONS PRIOR TO INSTALLATION

5
INSTRUCTIONS FOR THE USER
0402_2501
The central heating system is disabled when the selector (1) is turned to Summer position ( ). All boiler safety systems
(the anti-freeze system and the pump and three way valve anti-blockage systems) and the domestic hot water system
remain active.
Important: When you first switch the boiler on, the burner may fail to light and the boiler may block until all the air is
expelled from the gas supply pipe.
If this happens, simply turn the selector (1) to ( ) for at least 1 second, then repeat the burner lighting process until pure
gas reaches the burner and it lights.
Legend:
1 Summer-Winter-Reset selector
2 Central heating function indicator
3 Domestic hot water (DHW) function indicator
4 Flame indicator
5 Display
6 Central heating temperature control knob
7 Domestic hot water temperature control knob
8 Pressure gauge
Figure 1
To correctly light the burner proceed as follows:
1) provide power supply to the boiler;
2) open the gas cock;
3) follow the directions given below regarding the adjustments to be made at the boiler control panel.
Initial lighting of the boiler must be carried out by a licensed technician. Ensure the following operations are carried out:
a) compliance of boiler parameters with (electricity, water, gas) supply systems settings.
b) compliance of installation with the laws and regulations in force.
c) appropriate connection to the power supply and grounding of the appliance.
The names of authorized Service Centres are listed on the accompanying sheet.
Failure to observe the above will render the guarantee null and void.
Prior to commissioning remove the protective plastic coating from the unit. Do not use any tools or abrasive detergents
as you may spoil the painted surfaces.
2. INSTRUCTIONS PRIOR TO COMMISSIONING
3. COMMISSIONING OF THE BOILER