Water pressure issues

[marmaduke]

I've had water pressure issues for ages now, the system has been temperamental for a long time, sometimes working fine for months, then this stuttering flow from the taps when you turn them on.

I just bought a water filter for the first time, as I'd never had one and thought it might have something to do with that essential missing element. However, I've just installed it and the whole system appears to have gotten worse. See the video below:

http://youtu.be/Bpt6lJXnLL0

Here's how it's connected: Under the kitchen sink plumbing. The feeder pipe from the water tank is connected to the water filter which connects to the shurflo 20psi water pump, which connects to the air accumulator, then gets split into hot and cold and out to the rest of the system. The rest of the system is the kitchen sink, the bathroom basin and shower mixer at the back of the boat.

I'm wondering if perhaps it's air in the system that I can't get rid of. I have turned on all the taps though and this hasn't done anything. Although when I did do this, there wasn't enough pressure from the pump for all taps to flow.

One other point, the air accumulator is from 1977, although it does appear to be fine from the outside.

Any ideas on what I should do?

M

[blackrose]

I couldn't tell from the video, but your filter only really needs to be in line with the tap you drink from and perhaps fill the kettle from, not the entire system.

 

Perhaps the accumulator has died. It is quite old. With the water pump switched off and a couple of taps open, the accumulator pressure should be set at 3 or 4 psi below the pump's cut-in pressure.

Edited November 9, 2013 by blackrose

[Tony Brooks]

If it really is a filter as opposed to a strainer then I agree with Blackrose. Filters, in the main, only serve one special tap. A strainer goes into the inlet pipe between tank and pump. You may already have one that is blocked. It has a sort of tea strainer gauze inside it.

 

AS much of the video as I could watch on my slow BB connection shows that the pump appears to be sucking air. Is the tank full? Have you checked all the connections between tank and pump, including any gland on the main isolation valve?

 

If you do not know the pump cut in pressure then set the accumulator to about half its cut out pressure. That is near enough and will indicate it its an accumulator pressure problem..

[marmaduke]

Thanks both.

 

Further info: it's a shurflo strainer, SHURFLO FILTER / STRAINER 1/2" - TWIST ON - IN-LINE. It's between the main water on off and the pump. The accumulator has no switches or anything that I can change. Only says it's pressure tested to 200psi. The pump is 20psi. The water tank is full, though it looks like there are air bubbles coming up into the pump (it's a clear hose connecting so I can see).

 

No idea what's going on.

 

One thing that has changed for the better however is the pump no longer sounds like a machine gun as it used to. Now nice and quiet as it should be.

[Tony Brooks]

You may have a non-bladder type accumulator. If so unscrew it from the connecting T (which must be at the bottom on this type) and empty all the water out of it & refit.

 

The better ones with bladders have a plastic cap, usually disk shaped with a small round up-stand in the middle on the opposite end to the water connection. This unscrews to reveal a car type tyre valve.

[ditchcrawler]

Thanks both.

 

Further info: it's a shurflo strainer, SHURFLO FILTER / STRAINER 1/2" - TWIST ON - IN-LINE. It's between the main water on off and the pump. The accumulator has no switches or anything that I can change. Only says it's pressure tested to 200psi. The pump is 20psi. The water tank is full, though it looks like there are air bubbles coming up into the pump (it's a clear hose connecting so I can see).

 

No idea what's going on.

 

One thing that has changed for the better however is the pump no longer sounds like a machine gun as it used to. Now nice and quiet as it should be.

Probably a silly question but the valve between the pump and the cold water storage tank is fully open , not just the leaver of knob in the right place. If it is partly closed it will restrict the flow to the pump and could cause it to suck air in

[marmaduke]

Hi all, thanks for your help. I worked out what the problem was finally. Instead of actually looking at every element in the chain, I decided to replace every bit I could see. a complete waste of time...a lesson learnt there! So in this instance I had to jigsaw away a bit of floorboard to see properly what was happening when the feeder pipe was coming in. Once I could see that, it turned out that there was an ancient filter/strainer attached to the mains valve which was dripping. I suspected from there that this was the source of the air getting in. I removed it, tarted it up down there and switched everything on. Would you believe it, a quiet pump, constant temperature in the shower, and a pressure I've never before witnessed in the 3 years living on this boat! Feeling simultaneously heroic and imbecilic. If anyone else has this sort of problem in the future, check for leaks between the feeder pipe and the pump before doing anything else. Thanks again all. M

[Keeping Up]

Glad to hear you got it sorted marmaduke.

 

 

You may have a non-bladder type accumulator. If so unscrew it from the connecting T (which must be at the bottom on this type) and empty all the water out of it & refit.

 

The better ones with bladders have a plastic cap, usually disk shaped with a small round up-stand in the middle on the opposite end to the water connection. This unscrews to reveal a car type tyre valve.

 

Many of the non--bladder type have a blanking plug in the top that you simply unscrew after turning the pump off and after turning on a tap whose outlet must be below the level of the bottom of the accumulator (this can be achieved by attaching a short piece of hose to the tap if necessary) so that there is no need to disturb the T-piece