Salamander Negative Pump Pulsing issue

Post new thread

Discuss Salamander Negative Pump Pulsing issue in the UK Plumbers Forums area at PlumbersForums.net

B

budedwards

Messages
9
Recently had a Negative pump fitted that was sourced used to keep costs low. The pump has followed all the tests provided by Salamander support and runs perfectly. However when hooked up to the Thermostatic valve it pulses. 6 seconds on, half second off, 6 seconds on and so on.

If i remove the shower hose from the thermostatic valve this increases the pulse time to around 20 seconds on and half second off.

I have purchased the widest bore shower hose i could find 12mm but this has made little difference.

I am not convinced i needed a negative pump..

anyone ever come across this issue?

The CWT is in the loft and the shower is on the floor below the other side of the hot water tank.
 
Where is the pump fitted ?
 
ShaunCorbs said:
Where is the pump fitted ?
Click to expand...
Hi Shaun,

The pump is fitted in the cupboard next to the Hot Water Cylinder.

IMG20220724104156.jpg
 
Did you check the vessel charge on top when empty ?

Also you haven’t plumbed it in to spec eg s flange ?
 
Should be like this as the way you have it can lead to air coming in via the vent and stopping the pump

1658662592663.png
 
Problems are it's a salamander, it's been installed by a half wit, it looks like it tees off of the cylinder cold feed and hot same as above.
 
SimonG said:
Problems are it's a salamander, it's been installed by a half wit, it looks like it tees off of the cylinder cold feed and hot same as above.
Click to expand...
so which problem is causing the pulsing?

Here is the pipework consideration.

I'll happily get in a different plumber if the issue is the setup

Also i was trying to determine if it was a negative pump i needed all along but no-one has mentioned that as a potential issue.

IMG20220724180106.jpg
 
Plumber is the issue and negative head wouldn’t effect / cause the pulsing
 
That's not a plumbers work, maybe handyman or diy.

Not enough info on if a negative head shower is required.

How did you keep costs low on the negative head pump?
 
SimonG said:
That's not a plumbers work, maybe handyman or diy.

Not enough info on if a negative head shower is required.

How did you keep costs low on the negative head pump?
Click to expand...

Second hand pump
 
ShaunCorbs said:
Plumber is the issue and negative head wouldn’t effect / cause the pulsing
Click to expand...

I've asked another plumber to quote.

watching plumbers youtube channels they do seem to fit the pumps in the same way so this is a common issue/mistake i'm guessing.

They say the rule of thumb is use a negative head pump if you are getting less than 1Ltr per minute flow, i am getting around 3 Ltr per minute so on that basis i could of gone for a positive head.
 
New posts

Reply to Salamander Negative Pump Pulsing issue in the UK Plumbers Forums area at PlumbersForums.net

Newest Plumbing Threads

Back
Top