Doesnt cool as well as have been told

Does the temp continue to drop?

Generally 40 feet for ordinary atmospheric-vented household water heater...
Straight run to roof.
Atmospheric means no power vent... just hot air drafting upwards
Google search: gas vent height code

Atmospheric venting code depends on 4 basic factors:
Diameter of vent--- bigger vent, more draft
How many water heaters are connected to same vent
BTU per hour rating of water heater-- the more gas that is burned per hour, the bigger the vent needs to be
How straight the pipe is -- are there any horizontal or lateral runs
http://www.ameri-vent.com/files/assets/files/1366372183_Sizing26ApplicationGuide1.pdf

http://waterheatertimer.org/pdf/Bosch_Checking_the_draft.pdf
http://waterheatertimer.org/pdf/checking-the-draft2.pdf

Other factors can include
-wind conditions... higher wind across top of vent pipe on roof can reduce draft, and cause downdraft that blows deadly CO into same room as water heater
-vent termination near high walls, trees, high roof peak etc will reduce draft or cause downdraft
-amount of incoming air supply... if water heater is inside a closed room, then there is no air to draft up the pipe, burner will shut down or burn lazy yellow instead of clear blue
-stuff piled up around water heater that obstructs air intake
-dirty air intake screen that reduces air intake
-vent fans inside same room as water heater that pull air down the vent and cause reduction in water heater draft
-generally elbows reduce draft by 10%
-vent cannot terminate near any window door or air intake for another gas appliance
-bird build nest on top of vent pipe after vent termination falls off
-highly acidic gas by-product causes large amount of condensation inside pipe that burns hole in pipe or drips down and damages combustion parts...blower and inline condensate trap and drain might be required
-multiple water heaters installed on same vent line.

Gene
Water Heater Timers Save Money

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

try another dealer here in this case or a local bodyshop who may have a better idea ,these open top cars of all brands are tempremental and to top it all you get sunburn on the head ,give me a fixed roof anytime ,with a sun roof if you really want one .car is lighter as well owing to the motorised lifting stuff unles its a old morris minor or a old MG miget

wd40 does miracles

the most common problem with those retractable hard tops are leaking hydraulic cylinders. check the insides of your trunk where the top down cylinders are located if there's a leak,and also check the level of the hydraulic fluid situated near the right brake lights.
in your slk manual, there are instructions on how to manually close the roof when the hydraulics fail.

If it's leaking inside where filter cover is, then real good chance the drains being plugged is the only problem. If water (condensation) not running off roof when operating in cool mode, then I'd bet drains, which are located under unit on roof, and you should see them sticking down like buttons. They have a hole in side that needs cleaning with a pipe cleaner or similar to open them up. If need be, shut off power to unit and remove top cover on roof unit and look for the drain holes in base, and clean them out. If water comes in while raining, but AC not running, then it's gasket. That is remedied by removing ceiling assembly (just screws) and 4 bolts that pull/hold the upper and lower assemblies together, unplug wiring to upper unit, and simply lift it off, change gasket and re-install. Tighten those 4 bolts equally when gasket is aligned properly over hole, only until gasket is approx 1/2, original thickness. Plug harness back in and your done. (about an hours work.) Only other thing that may be wrong is styrofoam drip tray for cooling unit, under cover on roof may have a crack , allowing condensation to leak in. If that 's the case, you can try to find a sealant compatible with styrofoam to seal those cracks.

Yes, very possible!. The bathroom fan is connected together, and the upstairs one is down-drafting to you. Have the exhaust checked for blockage, or buy a fan that has a built-in damper that closes the exit when not in use.

It sounds more like the pilot is being blown out by drafting.If there is any open shielding at or below the pilot light line , it is very possible for it to blow out.Hold a tissue between your fingers and ck for drafts around the burner and pilot area. If it's the case, The drafting needs blocking.the exhaust will still exhaust because of the heat it generates and confined location in the combustion chamber. Good Luck.

Yes , its much more labor intense but it can be done by venting it up through the wall then through the attic over to the side vents. Make sure to get flexable duct to pull up through the wall.
Phil

Use Cooktop Cleaner with a soft micro cloth. Don't use water. Buff until the mark disappears. Hint: Never clean the cooktop until it is completely cool to touch as doing so makes cleaning much harder. Never use abrasives on the glass or abrasive cast iron skillets.