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Topic: Hydraulic fan controller (Read 2042 times) previous topic - next topic

Re: Hydraulic fan controller

Reply #25 –
I was just out at the coach and had removed the factory control valve and installed a needle valve. Closed is 100% and opened very little dropped to zero fan speed. A 1/4 of a turn the fans stopped. This shows that my system will operate once I install the new valve. I opened up the solenoid to look for something plugging it but was clean. Greg thank you for posting. It has really helped me decide how I want to do this in the coming weeks.
Scott

Re: Hydraulic fan controller

Reply #26 –
Quote from: dsd –
I was just out at the coach and had removed the factory control valve and installed a needle valve. Closed is 100% and opened very little dropped to zero fan speed. A 1/4 of a turn the fans stopped. ...
Scott
The oil volume through the controller is to bleed off pressure. The pressure is what pilots the valve on the front fan motor. The way it's made, very little change in volume effects a sizable change in pressure at the pilot.

An FYI for those who may be concerned about IAT getting high when the fans are running slow, Blue Bird used a thermo switch that would open when the intake air temp exceeded 150F. (See attachment) The switch operates a, series plumbed, N.C. solenoid valve in the pilot circuit, prior to the wax controller. In this way, the fan speed can be increased when the IAT exceeds the temp of the thermo switch, independent of coolant temp. This is something I'm considering.

Greg
Greg & Cathy
2000 U320 4010 DGFE Build #5650
Had: 1999 Tradewinds 7370

Re: Hydraulic fan controller

Reply #27 –
Quote from: MisterEd –
T
An FYI for those who may be concerned about IAT getting high when the fans are running slow, Blue Bird used a thermo switch that would open when the intake air temp exceeded 150F.

Greg
This really makes sense. That link is such a pleasure to read. Shame FT doesn't have the same. I agree that would be a good addition. Says it runs fans at 50% for cac cooling.
Thank you again.
Scott