Water coming thru coffee maker very slow

SOURCE: my bunn is too slow

Use the de-liming spring to clean the copper tube behind the spray head. Pour several pots of clear white vinegar through the unit to further remove lime and scale from the interior of your coffee maker. My Bunn is 24 years old, and the only replacement parts I've ever required are new carafes and the 4041 silicone washer repair kit.

SOURCE: Bunn coffee drips slow

I had the same issue, poured in 8 and out came 6. Here's what I did to clean and fix.
1) Unplug the NHB
2) Remove accessories like the pot and basket
3) Bring NHB over to the sink
4) Snap off the entire top cover (not the swing lid) by starting at the front and lifting upward (the top cover is about 1/4" thick). The back of the top cover will pivot a bit and then pop off exposing the pour reservoir. Remove the flow stopper inside the pour reservoir by lifting it straight up.
5) Place the top cover and flow stopper aside.
6) Remove the brew diffuser (located underneath the top where the brew basket goes. Twist counterclockwise gently but forcefully enough to snap it past the lock tabs which hold it in place. You'll know that it you've done this correctly when it just falls out.
7) Still over the sink, tip the NHB in a fashion where the back side is facing upward and the brew side is facing down into the sink. You'll be holding the NHB horizontally by the top and bottom of the unit. This will allow any water in the tank to pour out the brew spout. Begin to tip the unit as if tipping upside down as this will allow any remaining water to drain out. If this does not work the brew spout hose may be clogged and you can just tip the unit entirely upside down to empty it from the fill hole in the pour reservoir.
8) Return the NHB to the upright position in the sink.
9) Using a scotch brite sponge and some baking soda, clean the inside of the pour reservoir and rinse.
10) Using the tool Bunn provided, clean out the brew spout hose which is located under the brew hat. This is the little hole where the water comes out. If you don't have the tool Bunn provided you could use something like a plastic tie-wrap. Don't use anything metal as the hose you're cleaning is made of plastic tube and could become punctured. Clean this hose for just a minute or two to ensure that there are no significant obstructions.
11) With the NHB upright in the sink, pour a slow stream of hot water from the faucet, about two cups, directly into the fill hole located in the pour reservoir.
12) Tip the unit horizontally, as in step 7, and place the tip of your finger over the pour reservoir fill hole covering it completely.
13) Shake the unit back and forth horizontally so the water in the tank splashes around and frees anything which may be built up in the tank. Some water may splash out of the brew spout hose.
14) Tip the unit as in step 7 to drain the tank water out.
15) Fill a 16 ounce glass with hot water and 2tbsp baking soda, mix and pour into the pour reservoir fill hole.
16) Repeat steps 13 and 14 once.
17) Repeat steps 11 through 14 three times.
18) Clean the pour reservoir cover, swing lid and flow stopper.
19) Put the flow stopper back in place.
20) Attach the top cover.
21) Clean the exterior of the NHB.
22) With the boil and warmer switches off, plug the NHB into the electrical outlet.
23) Turn the boil and warmer plate switches on.
24) Fill the NHB with one pot of cold water and close the swing lid. Wait one minute.
25) Fill the NHB with another pot of cold water. Place the pot on the warmer plate and close the swing lid. If water does not yet come out, fill with one more pot of water.
26) Allow water to drain from brew spout until it stops draining.
27) Empty pot.
28) Fill pot to 10 cup line and pour into the NHB. You should find that the NHB now delivers 10 cups back to the pot. Empty the pot.
29) Clean brew spout diffuser and replace back in the brew hat.
30) Clean the pot, pot lid and brew basket.
31) Wait ten minutes for the water in the tank to boil.
32) Brew your coffee as you normally would.

The only issue I experienced during this process was with the warmer plate switch. It appeared that the light in the switch blew although the warmer plate still warmed normally. Shortly after the water in the tank started boiling the warmer switch light started operating again.

SOURCE: cleaning

The metal proble is use to clean out the water tubing. Remove your sprayhead and insert the metal rod up in the hole leaving out about 1-2 inches. Then simply twist and turn the rod about 5-6 times. This will remove any lime deposits. Then flush out with 2-3 decanters of water. You can obtain a new manual by calling customer service or going to the website-www.bunn.com going to @home, then products-click on your brewer-and then select use and care manual and you can print it out or view it online.

SOURCE: My coffee maker takes 20

The first suggestion is de-calcify as the heating element is probably coated. The following should explain what I mean.

Most likely you have calcium flake deposits clogging the orifice/jet/valve, that restricts the flow of water until heated properly. As the water starts to flow the flakes collect and block the water flow. Periodic cleaning will cure this and prevent damage to the, orifices, jets,valves and heating elements of your machine ( as calcium builds up it tends to insulate the heating element thus requiring more energy/heat to complete the task). Eventually the heating element will over heat and burn out. Periodic cleaning extends the life of the machine plus the added bonus of a better tasting " Cup of JOE".
Most any cleaning preparation designated for a "Mr. Coffee " type machine will do the job. If you want a home remedy 3-4 tablespoons of white distilled vinegar per cup of water ( calculate for the size of your water reservoir ). But please do it outside on the patio, as the vinegar tends to be in competition with the air freshener, and will win.

sincerely,
Doc Michael