Baxi 80 HE User Manual

[Page 1] Baxi Combi 80 HE Plus

Baxi Combi Instant 80 HE Baxi Combi Instant 105 HE Gas Fired Wall Mounted Condensing Combination Boiler Installation & Servicing Instructions Please leave these instructions with the user ...

[Page 2] Baxi Combi 80 HE Plus

2 Natural Gas Baxi Combi Instant 80 HE G.C.N o 47 075 17 Baxi Combi Instant 105 HE G.C.N o 47 075 19 The boiler meets the requirements of Statutory Instrument “ The Boiler (Efficiency) Regulations 1993 N o 3083” and is deemed to meet the requirem...

[Page 3] Baxi Combi 80 HE Plus

Installer Notification Guidelines 3 Choose Building Regulations Notification Route Contact your relevant Local Authority Building Control (LABC) who will arrange an inspection or contact a government approved inspector LABC will record the data and ...

[Page 4] Baxi Combi 80 HE Plus

Legislation 4 Codes of Practice, most recent version should be used IMPORTANT - Installation, Commissioning, Service & Repair This appliance must be installed in accordance with the manufacturer’s instructions and the regulations in force. Read...

[Page 5] Baxi Combi 80 HE Plus

1.0 Introduction 5 1.1 Description 1. The Baxi Combi Instant 80 HE or 105 HE is a fully automatic gas fired wall mounted condensing combination boiler. It is room sealed and fan assisted, and will serve central heating and mains fed domestic hot wate...

[Page 6] Baxi Combi 80 HE Plus

2.0 General Layout 6 2.1 Layout 1. Air Pressure Switch 2. Expansion Vessel & Pre-Heat Store 3. Burner Manifold 4. Automatic Air Vent 5. DHW Plate Heat Exchanger 6. Circulation Pump 7. Drain Off Point 8. Pressure Relief Valve 9. Position for Optio...

[Page 7] Baxi Combi 80 HE Plus

3.0 Appliance Operation 7 NOTE: All delay timers mentioned in 3.1 and 3.3 are overridden by domestic hot water demand. 3.1 Central Heating Mode (Fig. 2) 1. With a demand for heating, the pump circulates water through the primary circuit. At a pre-det...

[Page 8] Baxi Combi 80 HE Plus

3.0 Appliance Operation 8 3.3 Domestic Hot Water Mode (Fig. 4) 1. Priority is given to the domestic hot water supply. A demand at a tap or shower will override any central heating requirement. 2. The flow of water will operate the DHW flow switch wh...

[Page 9] Baxi Combi 80 HE Plus

4.0 Technical Data 9 4.1 Combi Instant 80 HE Temperatures C.H. Flow Temp (adjustable) 35°C to 85°C max (± 5°C) D.H.W. Flow Temp 35°C to 65°C max (± 5°C) dependent upon flow rate 50°C Pre-heat OFF 65°C Pre-heat ON ± 5°C dependent upon flo...

[Page 10] Baxi Combi 80 HE Plus

4.0 Technical Data 10 4.2 Combi Instant 105 HE Temperatures C.H. Flow Temp (adjustable) 35°C to 85°C max (± 5°C) D.H.W. Flow Temp 35°C to 65°C max (± 5°C) dependent upon flow rate 50°C Pre-heat OFF 65°C Pre-heat ON ± 5°C dependent upon f...

[Page 11] Baxi Combi 80 HE Plus

5.0 Dimensions and Fixings 11 Dimensions A 780mm B 345mm C 450mm D 116mm Ø Min. E 185mm F 190mm G 131mm Domestic Hot Water Outlet (15mm) Cold Water Inlet (15mm) Heating Return (22mm) Heating Flow (22mm) Pressure Relief Valve (15mm) Gas Inlet (22mm...

[Page 12] Baxi Combi 80 HE Plus

6.0 System Details 12 6.1 Information 1. The Baxi Combi Instant 80 HE and 105 HE Condensing Combination Boilers are ‘Water Byelaws Scheme - Approved Products’. To comply with the Water Byelaws your attention is drawn to the following installation...

[Page 13] Baxi Combi 80 HE Plus

6.0 System Details 13 6.5 System Filling and Pressurising 1. A filling point connection on the central heating return pipework must be provided to facilitate initial filling and pressurising and also any subsequent water loss replacement/refilling. 2...

[Page 14] Baxi Combi 80 HE Plus

6.0 System Details 14 6.8 Domestic Hot Water Circuit (Fig. 8) 1. All DHW circuits, connections, fittings, etc. should be fully in accordance with relevant standards, the water supply regulations. 2. Your attention is drawn to: for GB: Guidance G17 to...

[Page 15] Baxi Combi 80 HE Plus

7.0 Site Requirements 15 7.1 Location 1. The boiler may be fitted to any suitable wall with the flue passing through an outside wall or roof and discharging to atmosphere in a position permitting satisfactory removal of combustion products and provid...

[Page 16] Baxi Combi 80 HE Plus

7.0 Site Requirements 16 7.3 Ventilation of Compartments 1. Where the appliance is installed in a cupboard or compartment, no air vents are required as the appliance will run sufficiently cool without ventilation. 7.4 Gas Supply 1. The gas installati...

[Page 17] Baxi Combi 80 HE Plus

7.0 Site Requirement 17 7.6 Condensate Drain FAILURE TO INSTALL THE CONDENSATE DISCHARGE PIPEWORK CORRECTLY WILL AFFECT THE RELIABLE OPERATION OF THE BOILER The condensate discharge pipe MUST NOT RISE at any point along its length. There MUST be a fa...

[Page 18] Baxi Combi 80 HE Plus

7.0 Site Requirements 18 7.7 Flue NOTE: Due to the nature of the boiler a plume of water vapour will be discharged from the flue. This should be taken into account when siting the flue terminal. 1. The following guidelines indicate the general requir...

[Page 19] Baxi Combi 80 HE Plus

7.0 Site Requirements 19 7.8 Flue Dimensions The standard horizontal flue kit allows for flue lengths between 100mm and 685mm from elbow to terminal (Fig. 14). The maximum permissible equivalent flue length is: Instant 80 HE 4 metres Instant 105 HE...

[Page 20] Baxi Combi 80 HE Plus

20 7.0 Site Requirements 7.11 Flue Options 1. The Baxi Combi Instant 80 HE and 105 HE can be fitted with flue systems as illustrated. 2. The standard flue is suitable only for horizontal applications. 3. Maximum permissible equivalent flue lengths a...

[Page 21] Baxi Combi 80 HE Plus

8.0 Installation 21 8.1 Initial Preparation The gas supply, gas type and pressure must be checked for suitability before connection (see Section 7.4). 1. After considering the site requirements (see Section 7.0) position the fixing template on the w...

[Page 22] Baxi Combi 80 HE Plus

8.0 Installation 22 8.4 Fitting The Boiler 1. Remove the sealing caps from the boiler connections. 2. Lift the boiler using the lower edges. Engage the slots at the top rear of the boiler on the wall plate (Fig. 18). 3. Insert the sealing washers bet...

[Page 23] Baxi Combi 80 HE Plus

8.0 Installation 23 8.7 Fitting The Flue HORIZONTAL FLUE 1. The standard flue is suitable for lengths between 100mm minimum and 685mm maximum, as measured from the edge of the flue elbow outlet to the joint between the terminal and air duct (Fig. 20)...

[Page 24] Baxi Combi 80 HE Plus

8.0 Installation 24 8.7 Fitting the Flue (Cont) 5. Mark dimension ‘Y’ on the flue as shown (Fig. 23). Carefully cut the waste material from the flue, ensuring that the ducts are square and free from burrs. 6. The inner flue duct support bracket m...

[Page 25] Baxi Combi 80 HE Plus

8.0 Installation 25 8.8 Making The Electrical Connections To connect the mains input cable proceed as follows:- 1. Slacken the facia panel securing screws and lift the outercase panel so that its securing tabs are clear of the facia. Remove the panel...

[Page 26] Baxi Combi 80 HE Plus

9.0 Commissioning the Boiler 26 9.1 Commissioning the Boiler 1. Reference should be made to BS 5449 Section 5 when commissioning the boiler. 2. Open the mains water supply to the boiler. 3. Open all hot water taps to purge the DHW system. 4. Ensur...

[Page 27] Baxi Combi 80 HE Plus

9.0 Commissioning the Boiler 27 OUT MIN Burner Pressure Test Point Sealing Screw Fig. 34 9.2 Checking the Burner Pressure 1. Turn on the gas and electrical supplies to the boiler and ensure that all external controls are calling for heat. 2. Set t...

[Page 28] Baxi Combi 80 HE Plus

10.0 Completion 28 10.1 Completion 1. Hinge the facia panel upwards and refit the case front panel. Tighten the securing screws (Fig. 38). 2. Instruct the user in the operation of the boiler and system, explaining the operational sequence. 3. Carefu...

[Page 29] Baxi Combi 80 HE Plus

11.0 Servicing the Boiler 29 11 .1 Annual Servicing 1. For reasons of safety and economy, it is recommended that the boiler is serviced annually. Servicing must be performed by a competent person. 2. After servicing, complete the relevant Service Int...

[Page 30] Baxi Combi 80 HE Plus

11.0 Servicing the Boiler 30 11.1 Annual Servicing (Cont) 11. Ease the front edge of the left hand baffle upwards, disengaging the spring clip. Disengage the tab on the baffle from the slot in the fan hood (Fig. 42). 12. Undo the screws securing the ...

[Page 31] Baxi Combi 80 HE Plus

12.0 Changing Components 31 IMPORTANT: When changing components ensure that both the gas and electrical supplies to the boiler are isolated before any work is started. When the new component has been fitted turn the selector switch fully anticlockwis...

[Page 32] Baxi Combi 80 HE Plus

12.0 Changing Components 32 12.3 Heat Exchanger (Fig. 50) 1. Remove the fan as described in section 12.1. 2. Drain the primary circuit. Prise the three pipe connecting clips off the joints in the flow and return pipes. Remove the heat exchanger retur...

[Page 33] Baxi Combi 80 HE Plus

12.0 Changing Components 33 12.5 Injectors (Fig. 52) 1. Remove the burner as described in Section 12.4. 2. Undo the screws securing the injector manifold to the inlet elbow and remove the manifold. 3. Unscrew and replace injectors as required and exa...

[Page 34] Baxi Combi 80 HE Plus

12.0 Changing Components 34 12.8 Gas Valve (Fig. 54) 1. Undo the nut on the gas feed pipe under the boiler. 2. completely undo the securing screws and hinge the facia panel down. 3. Disconnect the wires from the valve modulator and the ignition lead ...

[Page 35] Baxi Combi 80 HE Plus

12.0 Changing Components 35 12.12 Pump - Head Only (Fig. 57) 1. Drain the primary circuit and remove the socket head screws securing the pump head to the body and draw the head away. 2. Undo the screw on the pump wiring cover and remove the cover. Us...

[Page 36] Baxi Combi 80 HE Plus

12.0 Changing Components 36 12.15 Pressure Gauge (Figs. 60 & 61) 1. Drain the primary circuit and undo the nut on the pressure gauge capillary. 2. Remove the timer cover and ease the timer wiring aside. Undo the screws securing the gauge retaini...

[Page 37] Baxi Combi 80 HE Plus

12.0 Changing Components 37 12.18 Pressure Relief Valve (Fig. 64) 1. Drain the primary circuit. 2. Disconnect the discharge pipe from the valve. Using a suitable hexagon key undo the grub screw sufficiently to release the valve. 3. Note the orientati...

[Page 38] Baxi Combi 80 HE Plus

12.0 Changing Components 38 12.21 Plate Heat Exchanger (Fig. 67) 1. Drain the primary circuit. 2. While supporting the heat exchanger undo the screws securing it to the brass manifolds. 3. Withdraw the heat exchanger upwards and to the left of the ga...

[Page 39] Baxi Combi 80 HE Plus

12.0 Changing Components 39 12.22 Diverter Valve Assembly (Cont) CH Pressure Differential Valve Diaphragm (Fig. 70) 1. Isolate the boiler from the central heating flow and return pipes and drain the boiler primary circuit. 2. Prise off the spring cl...

[Page 40] Baxi Combi 80 HE Plus

12.0 Changing Components 40 12.24 Secondary Heat Exchanger (Fig. 73) 1. Drain the primary circuit 2. Undo the four screws securing the right hand case panel. Remove the panel. 3. Prise the connecting clips from the heat exchanger return pipe and the ...

[Page 41] Baxi Combi 80 HE Plus

13.0 Illustrated Wiring Diagram 41 - brown - black - blue - red br bk b r - green - green / yellow - white g g/y w Optional Timers Domestic Hot Water Temperature Sensor Reset Selector Switch Control PCB 1 bk bk r r w bk g r g r 2 1 2 3 3 4 1 2345...

[Page 42] Baxi Combi 80 HE Plus

14.0 Fault Finding 42 Carry out initial fault finding checks 1. Check that gas, water and electrical supplies are available at the boiler. Electrical supply = 230V ~ 50 Hz. CH water system pressurised to 0.5 bar when the boiler is cold. The preferred...

[Page 43] Baxi Combi 80 HE Plus

43 14.0 Fault Finding Domestic Hot Water - Follow operational sequence Primary flow switch operated Fan runs at max speed. Pump runs Turn preheat control to on. Preheating function starts after 25 seconds. neon flashing. Primary water is diverted fro...

[Page 44] Baxi Combi 80 HE Plus

44 14.0 Fault Finding Turn selector to neon illuminated. Turn Central Heating thermostat to maximum. neon illuminated. Go to section ‘A’. neon flashing Go to section ‘B’. External controls calling for heat and where fitted, internal cloc...

[Page 45] Baxi Combi 80 HE Plus

14.0 Fault Finding 45 Burner output modulates until set temperature is reached. Burner goes out. Fan stops. Pump continues to run for 3 minutes. (room thermostat open) Operation sequence correct Go to section ‘G’. YES NO YES YES YES CH temperatu...

[Page 46] Baxi Combi 80 HE Plus

46 14.0 Fault Finding Fault Finding Solutions Is there 230V at: Is there 230V at: Main terminals L and N Check electrical supply 1. NO Main terminal fuse Replace fuse Replace main PCB neon illuminated 2. YES Selector terminals a & b and a & 3...

[Page 47] Baxi Combi 80 HE Plus

47 14.0 Fault Finding Check and correct if necessary 1. Electrical and pressure tube connections 2. Blockage of pressure tubes 3. Restriction in flue 4. Venturi NO E Replace air pressure switch Gas at burner Ensure gas is on and purged Replace main P...

[Page 48] Baxi Combi 80 HE Plus

48 14.0 Fault Finding Check and correct if necessary 1. Flame sensing electrode and lead connections 2. Flame sensing electrode position Flame current should be 1 µA approx. Replace main PCB Replace main PCB YES YES Replace flame sensing electrode N...

[Page 49] Baxi Combi 80 HE Plus

15.0 Short Parts List 49 Short Parts List Key G.C. Description Manufacturers No. No. Part No. 22 Fan (105) 5112430 Fan (80) 5112627 23 Pressure Switch (105) 248466 Pressure Switch (80) 5112999 32 Heat Exchanger 5112431 41 Burner 248029 44 Injector (...

[Page 50] Baxi Combi 80 HE Plus

CONTROLS To comply with the Building Regulations, each section must have a tick in one or other of the boxes TIME & TEMPERATURE CONTROL TO HEATING ROOM T/STAT & PROGRAMMER/TIMER PROGRAMMABLE ROOMSTAT TIME & TEMPERATURE CONTROL TO HOT WATE...

[Page 51] Baxi Combi 80 HE Plus

SERVICE 1 DATE ENGINEER NAME COMPANY NAME TEL No. CORGI ID CARD SERIAL No. COMMENTS SIGNATURE SERVICE 2 DATE ENGINEER NAME COMPANY NAME TEL No. CORGI ID CARD SERIAL No. COMMENTS SIGNATURE SERVICE 3 DATE ENGINEER NAME COMPANY NAME TEL No. CORGI ID CAR...

[Page 52] Baxi Combi 80 HE Plus

Comp N o 5111807 - Iss 2 - 03/05 BAXI POTTERTON A Trading Division of Baxi Heating UK Ltd Brownedge Road Bamber Bridge Preston Lancashire PR5 6UP After Sales Service 08706 096 096 Technical Enquiries 08706 049 049 Website www.baxi.co.uk 923.612.2 ...