Date:         Tue, 4 Aug 1998 14:25:42 -0400
Reply-To:     Dennis Haynes <dhaynes57@EMAIL.MSN.COM>
Sender:       Vanagon Mailing List <Vanagon@vanagon.com>
From:         Dennis Haynes <dhaynes57@EMAIL.MSN.COM>
Subject:      Re: How hot is HOT?
Comments: To: Ari Ollikainen <Ari@OLTECO.COM>, Vanagon@VANAGON.COM

The fan was probably cycling in high speed to cool the AC,(pressure switch).
This is normal.
Dennis

-----Original Message-----
From: Ari Ollikainen <Ari@OLTECO.COM>
To: Vanagon@VANAGON.COM <Vanagon@VANAGON.COM>
Date: Monday, August 03, 1998 9:59 PM
Subject: How hot is HOT?


>        It hit 100+ in my neighborhood today AND my HIGH-speed radiator fan
>        cycled on while running the AC and idling my 90/91 camper, waiting
in
>        line to pick up my daughter from summer day camp. The temp gauge
>        needle NEVER got more than a needle width toward HOT beyond the
LED.
>        This prompted me to think about what constitutes OVERheating versus
>        just normal operation in HOT ambient conditions. I found some
>        interesting numbers in Bentley:
>
>        Thermostat begins opening at 85C/185F; fully open at ~ 105C/221F
>
>        Thermoswitch for radiator fan     Stage I       Stage II   Stage
III
>
>        Cut-in temp                       89C-94C       95C-100C    ??
>                                         192F-201F      203F-212F
>
>        Cut-out temp                        81C            87C      ??
>                                           178F           189F
>
>        So...as long as the waterpump circulates coolant AND the faster
>        radiator fan cycles on and off, the cooling system is health and
>        doing its job?
>
>        If the cut-out temp for the thermoswitch for stage I is below
>        thermostat opening temp, this means that the thermostat closes
>        to keep the engine within normal OPERATING temperature? (DOH!)
>        Similarly, for stage II, the RRRRRRRR speed has to cool the
>        circulating coolant down to 189F before cutting off the fan, which
>        means, again that the thermostat would now be partially closed to
>        keep the engine within the normal temperature range...which would
>        tend to explain why there are no wild fluctuations of the needle
>        in my temp gauge when this is happening since the tempgauge sender
>        is on the engine side of the thermostat and thus in the "internal"
>        coolant circulation loop...Typically the needle reaches a needle
width
>        beyond the LED when the either fan speed cuts in. It's still
>        thereabouts when either fan speed cuts out. Is this normal?
>
>
>
>
>
>
>
>      OLTECO                         Ari Ollikainen
>      P.O. BOX 3688                  Networking Technology and Architecture
>      Stanford, CA                   Ari@OLTECO.com
>      94309-3688                     415.517.3519