Bilge Pump - Non return valve?

[pearley]

My calorifier PRV vents into the bilge, relying on the bilge pump then to dump it overside. I'm not in a position to fit a skin fitting at present so if I tee it into the bilge pump hose will it then pump overside or just run back down the hose, through the pump and into the bilge anyway?

[ditchcrawler]

Why not stop you valuable hot water coming out of the calorifier 

[Tony Brooks]

1 minute ago, pearley said:

My calorifier PRV vents into the bilge, relying on the bilge pump then to dump it overside. I'm not in a position to fit a skin fitting at present so if I tee it into the bilge pump hose will it then pump overside or just run back down the hose, through the pump and into the bilge anyway?

 

If yo T it into a downward led of a swan neck the water should not leak into the boat but I would not like dirty bilge water on one side of the prv.

 

I would also  ant to know why yours is leaking. If you have an expansion vessel on the hot water system make sure it is correctly pressurised and if not fit one. If it is because your water pump pressure is too high set it down. If the valve has  scaled open fit anew one but the bar rating is important.

 

In the latter case doing as you suggest may contaminate the domestic water.

 

[pearley]

Boat is only 4 months old but appears to have been built without an expansion bottle, at least I haven't found one yet. I intend to fit one but access is not easy. It has a 4 bar PRV, might be faulty as above, is new.

 

Difficult to say how much water is being vented. Not enough to ever bring the pump on automatically. Boat has been on a shoreline for last 3 months and immersion is set at whatever Surecal set it at and Eberspacher at whatever they have. Pump cycles at about 4am every morning.

 

Don't want to contaminate water so will put up with it until such time as I can do it properly.

Edited October 20, 2021 by pearley

[Tracy D'arth]

Surecal calorifier most likely has a non return valve in the cold feed to the bottom.  This will prevent the Accumulator Vessel on the cold feed from the pump seeing any expansion by heating.

So it should have an expansion vessel on the hot outlet pipe somewhere.

 Indeed, anywhere on a hot pipe will do the job.

[BEngo]

10 minutes ago, pearley said:

Don't want to contaminate water so will put up with it until such time as I can do it properly.

Edited 7 minutes ago by pearley

Do not leave it too long. Every time the PRV goes off it is because your cauliflower has been over pressurized. That leads to a short life for the cal.

The expansion vessel can be anywhere on the hot side of the cal, so fit it where it is easy to get at and pressurise it to pump cut out pressure.

N

[ditchcrawler]

1 minute ago, BEngo said:

Do not leave it too long. Every time the PRV goes off it is because your cauliflower has been over pressurized. That leads to a short life for the cal.

The expansion vessel can be anywhere on the hot side of the cal, so fit it where it is easy to get at and pressurise it to pump cut out pressure.

N

And the warranty will be void without it.

[Jen-in-Wellies]

+1 on fitting a hot side expansion vessel. Once that is done, the PRV should lift only rarely, or at all. Having it exit in to the bilge as it is now will highlight any developing problem, rather than hiding it by running the water overboard.

[Tonka]

Just put a bucket under it. Every few days you empty the bucket

[jonesthenuke]

2 hours ago, pearley said:

Boat is only 4 months old but appears to have been built without an expansion bottle, at least I haven't found one yet. I intend to fit one but access is not easy. It has a 4 bar PRV, might be faulty as above, is new.

 

Difficult to say how much water is being vented. Not enough to ever bring the pump on automatically. Boat has been on a shoreline for last 3 months and immersion is set at whatever Surecal set it at and Eberspacher at whatever they have. Pump cycles at about 4am every morning.

 

Don't want to contaminate water so will put up with it until such time as I can do it properly.

I suggest checking what the immersion and the Eberspacher thermostats are set to. With a new boat you are reliant on them being set correctly during installation rather than fitted with whatever setting was left after manufacture.

 

[Slim]

Is the boat 4 months old or have you just had it 4 months.? If the former why not take it up with the builder? Short term why not direct overflow into a plastic container?