Starrider

Hi Guys...

Well i got the AC working by having the leaking return hose replaced (napa part)
...however now the heater switch doesn't activate the heat?

Could something been effected with the heating system in the replacement of the AC return hose?

Or what is the usual culprit when there is no heat...the fan works ok... just cold air.

Thanks in advance...

DennisMik

iTrader: (2)

Check the small vacuum hose on the heater core water valve. It may have been pulled off.

arsonist63086

Make sure the heater valve moves freely and that it holds vacuum. If all that checks out you might have a clogged heater core .

ac max 92

iTrader: (13)

Was the heat working before the hose replacement? Could also be the thermostat or an air lock but if the heat was working before the hose replacement try checking to see if vacume hose on the heater valve was knocked off accidentally like previously stated.

DanNY

iTrader: (14)

left side of the manual HVAC control...flip it down.

Starrider

Was the heater working...i think yes. The service replaced the AC hose and serviced the air condition freon etc.

Anyone have a photo or diagram showing exactly where to look for the heater valve and vacuum hose connection?

Thanks Guys...appreciate all of you helping me to keep this old car running!!!

DanNY

iTrader: (14)

did you flip the lever down before you start digging under the hood?

Tiniform

The water valve is on the firewall with two small vacuum hoses going to it, if those are in tact the valve should operate when you move the lever inside over to heat.

Starrider

HI GUYS...

Ok ...i looked and couldn't find any vacuum hose out of place... so i went ahead and ordered a new water control valve for the heater.

Starrider

NO HEAT!... the tech says it's the heater valve solenoid and Nissan doesn't have it...???
What to do?...where can i get this heater solenoid? Thanks in advance...

Starrider

Part number for heater valve solenoid 92257 85E00...have been told Nissan no longer makes this part...?

Tiniform

Have checked and verified the valve is no good for yourself? It is quite easy to check, move the lever inside over to heat and see if there is any movement on the valve. It's easier if you had someone in the car while you look at the valve. Make sure the vacuum hoses are not dry-rotted and leaking. If you've verified the valve is bad the jy may be your best option to find one.

Starrider

Thanks Tiniform...
The tech showed me how to activate the defective solenoid: By first starting the car...setting the inside lever in heat position...then under the hood disconnect and reconnect vacuum hose ( inner closest to the firewall)... of the two solenoid vacuum hoses making a lever come out of the adjacent module and turning on the heat.

To return in to non heat position...slide the inside lever back to the left.

IN the mean time...we will keep looking for the preferable a new solenoid or used one.
........

Or what i have describe above indicate that the vacuum solenoid is still good?

oldpuck81

I replaced my heater flow valve w/ one from a salvage yard. Didn't help a bit. Hope you don't have a clogged heater core. A Maxima this age very well could have that problem. If your a/c tech drained the radiator, you may have the air bubble in the core and if it's all crusty and clogged like mine was, restoring enough coolant flow to give you heat is next to impossible. Does it make a gurgling noise when you drive it? If yes, then your heater core might be clogged. Search for my post on removing heater core 3 years ago. It's a b---- of a job, but will save you ~$1K if you can do it.

maximagician

few things not mentioned...
like danny said twice the fresh vent lever is often overlooked,the 1st 92 gxe i had the fresh lever moved but the plastic broke where the actual fresh vent cable that controls that flap door had broken free from the fresh vent lever,mine also had a warped track for the hot to cold slider

Like tiniform said you can watch the heater valve on the firewall move its arm when someone slides the hot\cold lever but it only closes the heater valve when the lever is on FULL COLD(as long as the contacts inside the hot cold slider are good)

Also oldpuck mentioned air pocket from filling coolant
without using the coolant air bleed bolt on the intake
(small sticker says never open hot)its a 10mm and dont overtighten it

And you could check the vacumm lines to the heater valve,1 goes to the intake manfold
(left back side)it has a hose diameter reducer and special end
i suppose the small vac lines on the valve could be routed more than one way

maximagician

And how could i forget about the thermostat,if its a failsafe type
it will fail open and the car will never fully warm up,
feel the upper and lower radiator hoses after the cars been running for a good while
if its a fail safe type thermostat and its open the lower radiator hose wont get hot

my 2nd maxima bought in 04',a 91 se 5 had no heat and the temp gauge stayed in the low 1/4 ,i pulled the thermostat and the fail safe has a rubber part that was more than halfway crumbled away it was probaly the original and had about 115k
it can be ninja'd in without removing much but its the famous nissan make your own gasket and put it on without smearing a bit on a nearby part ordeal,lol