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BT37 MarkII: Service Manual MA200606 1.0.0
Maintenance and trouble shooting
ADC errors and likely causes:
Most ADC errors are likely to be hardware failures.
These could be simple self-test single point failure which may be cleared by reset.
If alarm persists it indicates a component failure and a report should be made direct to
Planer.
4. Flow alarms
Likely causes include:
Gas must be supplied via a high purity regulator at 1.5 ± 0.15 bar ( 21.8 ± 2.2 psi ).
Check the regulated gas supply is within limits.
Leaks or incorrect fittings may cause loss of pressure.
Blocked or wet filters will restrict gas flow.
New inline gas filters (Ultrapure) may take some time to infuse gas to saturation.
Small fluctuations in gas flow occur during use. Gas flowing through the humidifier
window may look faster or slower depending on the position of the tubing.
Gas autochangers will most likely still allow a gas alarm on the BT37 as this is more
accurate than the autochanger settings. These can be adjusted using BT37 toolbox.
If gas flow reading is 600ml/min, it is likely that the flow sensor on the unit
motherboard has been subject to over pressure (inexcess of 1.5 ± 0.15 bar or 21.8 ±
2.2 psi) or is defective. This will require a motherboard replacement.
Gas flow is monitored per incubator and not per chamber. CO2 monitoring from the
exhaust ports is recommended for security and safety.
Excessive Gas Usage
Each BT37 should use 1350 litres of premixed gas per month. In the event that
excessive gas usage is observed, the following test is recommended
1. Close regulator on gas supply
2. Switch off BT37
3. Monitor gas pressure at cylinder
If the pressure drops this is suggestive of a leak between the cylinder and the internal
solenoid valve of the BT37.
Check connection at cylinder
Check connection at rear of BT37
Check internal gas connections
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