air trapped in boiler circuit

[cypher007]

ive just had a plumber fit a RM stelflow cylinder, move the pump to the tank cupboard upstairs, and fit a S plan. the trouble is when the system is running there is a loud tinkling noise where the boiler is, and the boiler seems to kettle somewhat. im guessing when the altered the system from gravity hw to fully pumped some air got trapped in the pipe work above the boiler. its most noticble when the pump turns off, and sounds like the glugging sound you get from a water bottle in an office.

I did point it out to the plumber who said I may go or just stay like it. my worry is it will not transfer the heat from the boiler efficiently (which might be the kettl'ing I can hear).

 

[SimonG]

Get him back and tell him to sort it. Could have screwed up position of pump. Take it the heating system is open vented?

 

[cypher007]

Get him back and tell him to sort it. Could have screwed up position of pump. Take it the heating system is open vented?

yes the heating is open vented. at our old house they fitted a air valve on one leg above the boiler, which seemed to me to be a good idea.

im wondering if the 28mm pipes run slightly down hill under the floor boards, thus causing the air to get trapped.

before you ask the old tank was gravity fed. so I have 28-22mm reducers at the tank cupboard and boiler.

 

[SimonG]

Cold feed and open vent connected at the cylinder?

 

[mike76]

Air bottles on pipework to cylinder, get the pressure up and run the system until all the air is pushed through the air bottles, this might take a few hours but its better than air in system, which will cause problems! System should be between 1 to 2 bar on pressure gauge!

 

[cypher007]

Cold feed and open vent connected at the cylinder?

its open vent only on the indirect coil in the cylinder. then the cold feed from the mains feeds the cylinder via a pressure regulator and expansion vessel. the plumber fitted the pump in a H format of pipe work, apparently this helps to avoid trapped air. the 2 pipes from the header tank feed into the tops of the H, and the pump pumps downwards on one leg.

 

[SimonG]

Its an unvented cylinder.

Picture please.

 

[cypher007]

Its an unvented cylinder.

Picture please.

this is the basic setup, scroll down:

RM Unvented Cylinder 250ltr Indirect Mega Flow Stainless Steel 25 Year Guarantee

 

[SimonG]

Need a picture in situ. Fitted a lot of these, I like them.

 

[kris]

If hes recently done the job then he has an obligation to come back to fix any snags, me personally dont trust pipework i cant see under floors etc so i always put airing points on different parts of systems for all the price of them, aswell as gate valves , i like to make my life easy when filling a system or removing parts, i hate lazy plumbers or tight asses who dont do this, boo hoo

 

[cypher007]

finally had time to take a pic, excuse the pipe insulation that's my effort at lagging it all, basically if it gets warm I lag it:

 

[Worcester]

If he didn't lag it it's non-compliant with building regs....

Actually looking at the picture it's non-compliant in lots of areas.
D1, Insulation ......
TMV?

"Primary circulation pipes for domestic hot water circuits should be insulated throughout their length, subject only to practical constraints imposed by the need to penetrate joists and other structural elements

All pipes connected to hot water storage vessels, including the vent pipe, should be insulated for at least 1m from their points of connection to the cylinder (or they should be insulated up to the point where they become concealed) "

 

[helpsy]

D1 500mm Max I believe.

 

[Worcester]

600 mm max from TRV... (3.54 and Diagram 1)

 

[Ermintrude]

That's horrific. Everything should be lagged within 1m of tank and as far as reasonably practicable.

 

[Ermintrude]

600 mm max from TRV... (3.54 and Diagram 1)

And on a continual downward fall, looks like back fall after tee on to the erv. So many plebs fail to see that erv can be anywhere after nrv and before cylinder . Expansion is throughout pipework not just at the tapping for the eRV.

 

[cypher007]

sorry to be a div, im a comp tech not a plumber, could you decipher the erv nrv stuff so I know what im checking.

on the lagging side I was a bit apprehensive about lagging the temperature relief valve, as I was worried it might make it more prone to venting.

well on a positive at least I knew, if only because im a tight git, that I needed to lag the pipes. by the way he didn't leave a lot of space to do it. I used 19mm where I could but had to use 13mm in places. also the foil tape from wikes doesn't stick well to the insulation, sticks to everything else though .

 

[Worcester]

NRV = Non return Valve, ERV = Expansion Relief Valve (aka Pressure Relief Valve), - In your system it's a combined control block (grey top on the Pressure Reducing Valve /Red top on the ERV and brass, this block also contains the non-return valve, so that hot water can't contaminate the cold water as it heats up) about 2/3 of the way down on the left.

Get your plumber back to fix it all.... If you want all the technical blurb it's in here: Planning Portal - Approved Document G - Sanitation, hot water safety and water efficiency

So he needs to sort out the air in the system AS well as you new hot water bomb. https://www.youtube.com/watch?v=9bU-I2ZiML0

 

[snowhead]

It's easy to criticise after the event.

You need to know the state of mind at the time, was he being over fed with tea and biscuits by the customer and got distracted or NOT being overfed by the customer and got vindictive??

Apart from he must have found the E.Vessel in the box just before he left and slapped it in front of everything, it's difficult to say..

 

[cypher007]

i did question the expansion vessel placement. he said he thought it was better there as i could put shelving above the tank or something like that. quite frankly i would have preferred storage in front of the tank where the door is, and that i don't need steps to reach.

on more serious note is there any definite no no's that need immediate remedies. i don't want to rub the plumber up the wrong way, especially as hes gonna wonder how i know the install is not right.

 

[brucethegas]

What I can't make out from the photo, which concerns the original post, is how the cylinder primaries vent.

 

[SimonG]

D1 used to be 500mm but was increased to 600mm

 

[cypher007]

above the pump there is a 22mm with two T's that goto 15mm runs upto the old rad circuit tank. one to the tank and one to the vent.

 

[cypher007]

need some help here. is this install dangerous or just not good. I contacted the plumber, as we had to put the boiler on today, and he says the boiler needs replacing as its probably scaled up. I tried explaining that the noise is a tinkling when the pump is running and a bubbling when the pump stops. also I told him if set the boiler to 5 the hw doesn't get very hot and the boiler turns off, if I set it to 6 (MAX) the boiler starts to kettle. here's a picture of the pipe work downstairs in the utility:

 

[cypher007]

the two 28mm runs that were utilised, I think have trapped air in them, under the floorboards upstairs.