TV stopping when Water is on

I tried running a 14V TV off of my 12V system. With the engine running it worked fine, but without I only got sound... no picture. Ended up using the 120V/14V power supply that came with it.
If you are running yours on 12V then the easiest solution may be running a separate 12V cord from your battery. What is the voltage at the TV when it stops working... both picture and sound?

If this happens only with the TV that's not in the bedroom its probably because the pump is affecting the 12VDC to the outlet that switches off when the ignition is turned on. You can work around the problem by plugging the TV into another outlet up front. But, if that's the case, I'd get the real problem with your 12VDC debugged and fixed.

Are you connected to the campground water system?

If so, turn off your water pump. You don't need it on.

You still have the 2005 Model? If so we need more info.
1. Does the RV still have the OLD style CRT TV's (Picture tube)?
2. Does the RV have updated LCD TV's?
3. Do any of the TV's have a 12 volt power source or are all TV's 120 volt?
4. What type of switchbox do you have to switch between Cable and roof top OTA(over the air) Antenna? Is it a multiple button pushbutton switch box? Is it just the standard wall plate booster with the On/Off button with indicator light?
5. These questions need answered before anybody can give you any constructive help. Doug

X2 for checking all connections.

That happens either with antenna or cable.
Thank you for your answers.

Can anything else cause disruption to my television reception?

Yes, some household appliances can produce what is referred to as ‘electrical noise’. This is usually caused by a device with a motor or thermostat, such as electric drills, can-openers and immersions. It is possible to find these items by noting whether the interference coincides with a particular appliance being in use.

Is the TV tuned to antenna or cable?

When tuned to antenna over the air reception it is not uncommon to get RF interference. The source of the interference could be any type of motor...even could be a microwave.

So are you using the antenna when this happens?

Easy enough to test the voltage with a voltmeter and see if it drops when the pump runs.
More likely RFI. If so you can try a small capacitor across the positive and negative pump leads as a filter.

If the TV is operated by 12 volts and is on the same circuit it could be a low voltage situation.

I would suspect it is electrical noise generated by the motor and a loose connector on a coax is letting the RF (radio frequency) interference do exactly that.

Tighten every connection you can find. If that does not help and you have a switch on a panel you have to activate to turn the antenna amp on watch that light with the water pump running. Try to do this while blocking out any light. Using a cardboard tube from a paper towel roll will do. See if the light dims or flickers. If so, you need to measure the voltage on the back of the panel with the pump running. In this case you will find some additional coax connectors that can be tightened as well. Measuring the voltage on the back of the panel will show if you are getting a low voltage problem that is causing an issue with the tv antenna amp.

This should give you some things to check. Be sure to include any other observations weather you think they are important or not.