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Installation, Commissioning and Servicing Instructions
Models covered by these instructions
Leave these Instructions with the User or with the appliance
WARM AIR HEATER
MODAIRFLOW and Conventional Control
INSTALLATION INSTRUCTIONS
This appliance has been tested and certificated by British Gas for use with natural gas.
1. COMPONENTS CHECK
Fig. 1
JB70-90 is an open-flued, fan-assisted, downflow ducted warm air heater, which may be supplied with Modairflow controls.
A basic (non-Modairflow) control is available as an option.
Air heater output can be adjusted between 20.5kW(73.9MJ/h, 70,000Btu/h) and 26.4kW(94.9MJ/h, 90,000Btu/h).
A free-standing kit FS65/90 is available with this appliance.
1. Air filter
2. Air circulating fan
(42-417-70) J70-90 Mk.2
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Table of Contents
Related Manuals for Johnson & Starley J70-90 MK2
Summary of Contents for Johnson & Starley J70-90 MK2
- Page 1 Installation, Commissioning and Servicing Instructions Models covered by these instructions (42-417-70) J70-90 Mk.2 Leave these Instructions with the User or with the appliance WARM AIR HEATER MODAIRFLOW and Conventional Control INSTALLATION INSTRUCTIONS This appliance has been tested and certificated by British Gas for use with natural gas. 1.
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Page 2: Ventilation And Combustion Air
3. Fan chamber door 4. Fuse 5. Time control 6. Connection for Thermist-stat/room thermostat 7. Terminal strip 8. Data badge 9. Overheat (limit) control 10. Secondary overheat control 11. Airflow sensor (Modairflow)OR fan delay control (non-Modairflow) 12. Pilot burner 13. Main burner assembly 14. -
Page 3: Duct System
When installed in a compartment, two permanent ventilation openings into the compartment are required, one at high level and one at low level, both communicating either directly with outside air or with a ventilated room or space. The minimum effective areas specified in Table 1 are related to the rated heat input of the air heater. - Page 4 c) Carry out a flow visualisation check with a smoke pellet at the intended position for the appliance. Ensure that there is no discharge of smoke from the correct terminal only, and no spillage into the room. Smoke coming out of other than the correct terminal only, or a downdraught or ‘no flow’ condition, indicates that the flue has failed the test, and the appliance shall not be connected until the defect has been found and rectified, and the test satisfactorily completed.
- Page 5 Overheat (limit) control setting is 190°F and must NOT be adjusted. With the fan chamber door and air filter removed:- Modairflow models: Set the fan selector switch to CONTINUOUS and turn the balancing screw fully clockwise (maximum speed). Non-Modairflow models: Set the fan speed transformer tapping to a number appropriate to the desired heater output, e.g. for maximum output set plug to number 5.
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Page 6: Safety Checks
Allow the heater to operate for 15 min., then adjust the burner pressure to the output required (see Fig. 3 Table NOTE: Heaters are factory set to a burner setting pressure giving high rate output i.e. 26.4kW(90,000Btu/h) at 10.6mbar(4.2in wg). To adjust the burner pressure, remove the cover from the gas pressure adjusting point (see Fig. - Page 7 Check for gas soundness within the appliance. Check that the flue operates effectively with heating system on, all doors closed and extractor fans, if fitted, running, then, after connection to the flue system, follow the lighting procedure and run the appliance for twenty minutes to preheat the flue. Use the following procedure to test for spillage: - a) If the draught diverter is accessible, introduce smoke, e.g.
- Page 8 f) That the air grilles on the heater or heater compartment, or any grilles or ventilators in the walls, windows and doors of the building must not be obstructed. g) That the heater must be serviced at least once a year by a competent person to ensure efficient and safe operation. h) That the red instructions for safe use have been pointed out and understood.
- Page 9 Unscrew the four screws securing the manifold assembly and remove the multi-functional control. (Make sure that the sealing ring is retained). Before refitting, check that the sealing ring is in good condition, and replace if necessary. 8.7 To remove piezo unit:- Disconnect the electrode lead(s) from the unit.
- Page 10 Disconnect the two overheat (limit) control leads at the terminal block on the side of the fan. Disconnect the fan input leads at the terminal block on the front of the fan. Remove the two fan retaining screws. Handling with care, withdraw the tan assembly. Remove all dust from both impeller and motor, taking care not to disturb the balance of the fan. To replace, reverse the above procedure.
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Page 11: Fault Finding
Remove the two securing screws and withdraw the control/sensor. 8.18 Secondary overheat control replacement:- With the electrical supply turned off and the fan chamber door removed (see 8.2), Partially withdraw the air circulating fan (see 8.10) to gain access to the control. Remove the electrical connections to the control, release the two securing bolts and remove the control. - Page 12 SYMPTOM POSSIBLE CAUSE REMEDY (iv) Loose connection on room thermostat, overheat control, secondary overheat control, gas control lead, Check connections for soundness. time control, or transformer. Check with test meter and replace electrical (v) Transformer open circuit. panel if necessary. (vi) Multi-functional control faulty.
- Page 13 Fig. 5a Circuit Diagram - J70-90 Mk.2 Air Heater with Modairflow control...
- Page 14 Fig. 5b Circuit Diagram - J70-90 Mk.2 Air Heater (non - Modairflow)
- Page 15 Fig. 6 J70-90 Mk.2 Air Heater - Principal Dimensions...
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