Fresh water tank

[M_R_E_]

I have a '15 Columbus which the fresh water tank was never used. When I winterize with air and drain , I always have a little bit of water come out of fresh water drain. I was going to sanitize my tank, but first flush it out. When I added some water nothing came out of the drain. I took an air hose and blew up the drain to possibly remove any blockage. Still no water coming out. I don't want to fill it and get stuck with a full tank. HELP

[laknox]

mhardin wrote:
Insects like to crawl up lines and build nests that cause blockages. Mud daubers are especially bad about it around here.

Also, the people building these things don't much like to clean tanks out after installing them and also have a nasty habit of dropping fitting cutouts back into the tank instead of pulling them out. How many of us have read about this when a black/grey tank won't drain?

Lyle

[way2roll]

M.R.E. wrote:
I wasn't blowing air up the low point drains for hot and cold water. It was the fresh water drain which also looks like a low point drain but is the fresh water drain. I pushed up the drain a coat hanger wire and felt a blockage and after going up and down for awhile it went up and drained the tank. I filled it and drained it and everything is fine. There must be some debris that blocked it.

That's awesome, glad you figured it out.

[mhardin]

Insects like to crawl up lines and build nests that cause blockages. Mud daubers are especially bad about it around here.

[M_R_E_]

I wasn't blowing air up the low point drains for hot and cold water. It was the fresh water drain which also looks like a low point drain but is the fresh water drain. I pushed up the drain a coat hanger wire and felt a blockage and after going up and down for awhile it went up and drained the tank. I filled it and drained it and everything is fine. There must be some debris that blocked it.

[way2roll]

M.R.E. wrote:
I only have gray and black water drains. Other low point drains are for hot and cold water drains.

I am not sure this is entirely accurate. You should have a fresh water tank drain as well as a low point drain. The FW tank drain does just that, drains the FW tank. The low point drain allows all the water to be drained from the system from all the lines. Your grey and black tank drains are waste drains and separate from your water system. Sounds like you need to find your FW tank drain.

[way2roll]

Breaking this down for my own understanding and clarification:

I have a '15 Columbus which the fresh water tank was never used.
So you have never used your FW tank?

When I winterize with air and drain , I always have a little bit of water come out of fresh water drain.
Where are you draining from? FW tank drain, low point drain? Could it be you simply just have a little water in the lines even if you never use your tank and always use City water? How much PSI are you using to blow the lines out? Have you switched the winterization valves?

I was going to sanitize my tank, but first flush it out. When I added some water nothing came out of the drain.
How much water did you add and where did you add it? FW tank fill, does yours have a valve to switch from City water to FW tank?

If I were to try and summarize; you have never used your FW tank - odd but ok. Is this 6 year old RV new to you and if so have the previous owners used the tank? When you drain, you have some water coming out. I am not sure how you know this is coming from your FW tank - could very easily just be water in the system. Have you ever used your water pump if you've never used your tank? Now you are concerned that if you do eventually use your FW tank it won't drain - despite claiming it's draining something despite not being used?

[Cummins12V98]

MFL wrote:

Cummins12V98 wrote:


Could be an internally leaking water pump.

Yup, that happens, can put water in tank, but OP states that he added water to tank, but nothing comes out drain?

Something is amiss, curious to hear outcome!

Jerry

Oops, reading and comprehension is fundamental.

[MFL]

Cummins12V98 wrote:


Could be an internally leaking water pump.

Yup, that happens, can put water in tank, but OP states that he added water to tank, but nothing comes out drain?

Something is amiss, curious to hear outcome!

Jerry

[Cummins12V98]

MFL wrote:
You say "fresh water tank never used", but yet a little water comes out when winterizing??

Sounds silly, but are you sure you are opening the fresh water tank drain, or maybe the low point drain?

Jerry

Could be an internally leaking water pump.

[valhalla360]

There should be a drain for the fresh water tank also...otherwise, you have to dilute with large amounts of antifreeze to protect the tank.

Blowing air up the low point drains shouldn't have any impact on the fresh water tank as there should be a one way check valve at the pump that would stop any flow back into the tank.

So it's not clear what issue you actually have.

[M_R_E_]

I only have gray and black water drains. Other low point drains are for hot and cold water drains.

[MFL]

You say "fresh water tank never used", but yet a little water comes out when winterizing??

Sounds silly, but are you sure you are opening the fresh water tank drain, or maybe the low point drain?

Jerry