SVL 90-2 AC blows Hot and cold

jwdoud

New member
Jul 22, 2017
3
0
0
Midland, SD, USA
I'm working on the AC system its cool but not cold. Replaced the compressor and clutch. Now I have everything in the cab torn apart. Out of the top vent it blows ice cold but the duct that leads to the front is blowing hot air. could it be the thermistor or is my valve not shutting all the way off on the core?
 

100 td

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B21TLB (B21, TL421 & BT751) Toyota SDK4 T116 Bobcat
Aug 29, 2015
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ɹǝpunuʍop
I don't know about your system, but many have gone away from the water valve inline feeding the heater core due to failures, yours may or may not have this valve, if it has, ensure it is opening/closing correctly/easily. The other system allows water to flow constantly in the heater core, then an air mix flap directs more or less air through the heater core, same thing here, if yours is this system, ensure that the air mix flap is opening/closing correctly/easily and totally shuts off the hot air.
 

BAP

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2012 Kubota 2920, 60MMM, FEL, BH65 48" Bush Hog, 60"Backblade, B2782B Snowblower
Dec 31, 2012
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New Hampshire
Simplest fix is to put a shutoff valve in the coolant line coming off the engine leading to the heater core. Keep it shu off during warm weather and open it up when you need heat. It is a common problem for the heater shut off valve in the cab to leak by. I have fixed a lot off tractors by putting the manual valve in the coolant line near the engine. Many times changing the valve in the cab is only a short term fix because the new one will fail too.
 

lugbolt

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ZG127S-54
Oct 15, 2015
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Mid, South, USA
could be a hundred different things; and quite honestly too many to list individually. Get the WSM, study it, and do your diag accordingly.

A/C work is NOT as easy as "you tubers" say it is.....actually one is "supposed" to keep/retain a MVAC license in order to "legally" replace "major components".
 

SidecarFlip

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M9000HDCC3, M9000HD, Kubota GS850 Sidekick
Oct 28, 2018
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Everything is 'easy' when it's on the Boob Tube.:D
 

SidecarFlip

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M9000HDCC3, M9000HD, Kubota GS850 Sidekick
Oct 28, 2018
7,197
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Simplest fix is to put a shutoff valve in the coolant line coming off the engine leading to the heater core. Keep it shu off during warm weather and open it up when you need heat. It is a common problem for the heater shut off valve in the cab to leak by. I have fixed a lot off tractors by putting the manual valve in the coolant line near the engine. Many times changing the valve in the cab is only a short term fix because the new one will fail too.
Standard issue on every big truck I've ever driven. Never seen one that didn't pass hot coolant. Think they all do to a certain extent.
 

zeroo

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rtv1100, kx 040-4, svl75wc
Jan 5, 2021
1
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1
kentucky
Did you figure out the problem? I have the same thing going on with mine.
I know this is older thread but I have a new svl75 and just figured out that the 2 top vent are fresh air only. they blow straight off the blower before the heating core or evaporator. keep shut for ac or heat, but they are part of the positive cab pressure, so open in dusty conditions and shut recirculate.