Start delay on Dometic air conditioner
My coach has two Dometic AC units and a 6,000 watt Onan quiet diesel genset. If both units are enabled when the generator is started they both hit the generator at the same time which overloads it an...
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There is a built in delay in the AC units that has nothing to do with the generator or shore power. This is to prevent the AC units from cycling the compressor on and off with a power surge. In other words, if you lose power and then it comes back on in a few seconds, your AC compressor will not come on until after the delay.
When you generator starts, IT IS NOT starting with a high load from the AC units since the compressor will not be coming on right away. Their fan will start first, which is a minimal load, and then the compressor will kick on a short time later. This is the normal cycle for an AC unit. It would be extremely odd if both AC units tried to kick on at exactly the same time, even if you have a dual zone thermostat.
Your generator should start and get up to full output power BEFORE the transfer switch kicks in and provides power to all systems in your coach. At that point, your generator should be able to handle the load from the AC units with no problem. I suspect that you have a problem in the generator output adjustment that it preventing the generator from maintaining the correct power when a load is applied. If the voltage drops too low, your Energy Management System will kick things offline.
When you generator starts, IT IS NOT starting with a high load from the AC units since the compressor will not be coming on right away. Their fan will start first, which is a minimal load, and then the compressor will kick on a short time later. This is the normal cycle for an AC unit. It would be extremely odd if both AC units tried to kick on at exactly the same time, even if you have a dual zone thermostat.
Your generator should start and get up to full output power BEFORE the transfer switch kicks in and provides power to all systems in your coach. At that point, your generator should be able to handle the load from the AC units with no problem. I suspect that you have a problem in the generator output adjustment that it preventing the generator from maintaining the correct power when a load is applied. If the voltage drops too low, your Energy Management System will kick things offline.
