I have a 2004 Land Rover Discovery. I've replaced the water pump as well as hoses in the past so I'm familiar with what to do when the the temp starts rising.
Currently my heat has stopped working, the fans are on but they are blowing out cold air. For the most part its intermittent. I get hot and cold air. I'm thinking it could be the heating core but I'd like to see if there are other options.
Today the temp started rising. I'm not driving it now because without heat to cool off the engine I don't want to fry anything.
Oh I also get a squeaking sound from the passenger side vent that seems to be causing the fan to stop and start.
Any ideas would be greatly appreciated PLEASE and THANK YOU from a girl just trying to figure it out!

 

It sounds like the heating core if it's intermittent. I would say thermostat would be a cheaper and easier try if you didnt change that when you changed the hoses.

 

Heater core in a D2 has water flow 100% of the time, no valves. Some reverse the lines to core to force sludge out, or reverse flush with a hose. Air control is by flaps. If you say temp is rising by the heat gauge, you are already in trouble. The gauge on a D2 is built to point at 50% from about 130 - 240F. A scanner or Ultra Gauge can show you what is really happening. Low coolant from a leak makes heat problems, plus head gaskets, slipped sleeve, etc. This could be an indicator of a much more serious issue. You don't want gurgle sounds under dash, from exhaust gas in coolant (bad) or air (leak - but you can purge this). You would like temps in the 180 - 200F range.

 

I think I heard some gurgling under the dash not too long ago. Did notice the coolant level being low. I'll add some coolant and cross my fingers. Wow, this thing needs so much attention,

 

It is worth mentioning that this discussion related to a D2. Why it occurred in the D1 section is a mystery.

If you have gurgling you should pressure test your cooling system. The top of the reservoir is rated to release pressure at 15 lbs so that is your target.

Gurgling suggests air entering the system which is unwanted. Air can be introduced via old hoses and clamps that don't do their jobs sufficiently, or it MIGHT be a head gasket allowing exhaust gasses into the cooling system.

An exhaust gas tester can be helpful (but often not 100% accurate) to determine if exhaust gasses are mixing with the coolant which would suggest a head gasket failure. https://a.co/d/1wLyZr1