Combo Boiler issues
- Thread starter RickH
- Start date
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"The vent pipe is normally connected to the PRV by a compression joint with an olive."
When I have seen PRV on external pressure vessels the vent pipe is as you say connected bu standard 15mm compression connection. but on this boiler the PRV is screwed onto the end of large horizontal manifold .... it then has a vent pipe push fit into the side, and held by a push in 'U' clip
Because the pipe after about 30mm has a 90 degree elbow and then is routed to back of boiler a few more 90 degrees elbows (all end fee solder elbows) and out through the wall .. I cannot pull pipe out of the PRV.
I will have to put a hacksaw through it and then add a coupler when I come to reassemble ... no play in pipe to get it out of the fitting otherwise
When I have seen PRV on external pressure vessels the vent pipe is as you say connected bu standard 15mm compression connection. but on this boiler the PRV is screwed onto the end of large horizontal manifold .... it then has a vent pipe push fit into the side, and held by a push in 'U' clip
Because the pipe after about 30mm has a 90 degree elbow and then is routed to back of boiler a few more 90 degrees elbows (all end fee solder elbows) and out through the wall .. I cannot pull pipe out of the PRV.
I will have to put a hacksaw through it and then add a coupler when I come to reassemble ... no play in pipe to get it out of the fitting otherwise
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OK ... pipe did vent into balloon .... so is this pretty likely to be faulty PRV ? .......... or is there a more likely cause of ovepressure ?
If it is likley faulty ... I'll get one tomorrow.
If it is likley faulty ... I'll get one tomorrow.
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I wouldn't say wasted, that leaking water will have rinsed it out ready to use again.
No ... corner cut off plastic bag 
...... last time I bought them, they were 3 for a £1
Anybody changed a PRV on Ravenheat ...CSI 85 ..... this is the item ........
I thought it screwed into manifold ... looks like its is just a push fit (o ring seal), presumably with a grub screw or similar.
...... last time I bought them, they were 3 for a £1Anybody changed a PRV on Ravenheat ...CSI 85 ..... this is the item ........
I thought it screwed into manifold ... looks like its is just a push fit (o ring seal), presumably with a grub screw or similar.
You've been advised before buy a new prv and that pro is not hard to remove just u clip it and replace .
Yeah they're the cock rings I use!
Me too, until just before I got to that stage in life where is wasn't necessary - then the bastads made them freely available.
OK ... replaced the PRV 2 weeks ago and no pressure loss since .... so 'hopefully' that was the issue.
Have a seperate problem regarding heat out put - will open new thread.
Have a seperate problem regarding heat out put - will open new thread.
Nice it theory .. but as explained the vent pipe had an almost immediate 90 elbow ... and then off to wall .. no play in pipe to allow any movement of pipe to the right (to get it out of the PRV)
I finally resolved by undoing all pipe clips on teh wall ... allowed me to be able to move pipes forward about 20mm (no sideways movement) and that was enough to get PRV out of the manifold, and then rotate through 90 degrees and then I could slide PRV off pipe (rather than remove pipe from PRV)
OK ... no problem ... Part 2
I know the concept on balancing, based on having an index rad (usually furthest away) crank that lockshield & control head open, and close all other to 1/4 turn open - as a starting point.
Adjust index rad for temp differential and then work backwards through other rads doing the same.
Question is can you fit a Thermostatic rad valve on the index rad ?
There isn't one now .... but may fit one as changing the rad.
Just trying to get my sons first house running properly .... index rad takes an age to get warm, even with lockshields down to only 1/4 turn on all other rads .... it does get hot .. but only after all the others ... and as this is in the lounge - not ideal, can be 1/2 Hr or more before it gets hot.
(previous owner advised always been the case)
Variable head pump is on max speed - so can't increase flow rate ........
Flushed & put cleaner in last week - will flush & install inhibitor this week end....... and at same time change the index rad .... going to put in a 1.8m x 0.4m Stelrad Compact K2 2468W.
Currently a twin panel 2150 rad .. but no convector fins, so will put out a fair bit more heat .... and if I can get it balanced better - will put it out sooner.
Hence the Q ... can you fit a TRV to the index rad, if no issue I will do that at same time.
Will also fit reflective foam insulation to wall behind rad when fitting new one.
I know the concept on balancing, based on having an index rad (usually furthest away) crank that lockshield & control head open, and close all other to 1/4 turn open - as a starting point.
Adjust index rad for temp differential and then work backwards through other rads doing the same.
Question is can you fit a Thermostatic rad valve on the index rad ?
There isn't one now .... but may fit one as changing the rad.
Just trying to get my sons first house running properly .... index rad takes an age to get warm, even with lockshields down to only 1/4 turn on all other rads .... it does get hot .. but only after all the others ... and as this is in the lounge - not ideal, can be 1/2 Hr or more before it gets hot.
(previous owner advised always been the case)
Variable head pump is on max speed - so can't increase flow rate ........
Flushed & put cleaner in last week - will flush & install inhibitor this week end....... and at same time change the index rad .... going to put in a 1.8m x 0.4m Stelrad Compact K2 2468W.
Currently a twin panel 2150 rad .. but no convector fins, so will put out a fair bit more heat .... and if I can get it balanced better - will put it out sooner.
Hence the Q ... can you fit a TRV to the index rad, if no issue I will do that at same time.
Will also fit reflective foam insulation to wall behind rad when fitting new one.
The whole concept of balancing is that its done with the lockshield valve with the other end open.
What is on the other end is not relevant during balancing as long as its open.
So you can fit a TRV anytime.
But its always best to recheck the balance after changing a rad.
Even a 1/4 turn on some valves is a lot of flow.
So try 1/8 turn if needed.
A tiny turn can make a big change to the flow rate.
Tony
What is on the other end is not relevant during balancing as long as its open.
So you can fit a TRV anytime.
But its always best to recheck the balance after changing a rad.
Even a 1/4 turn on some valves is a lot of flow.
So try 1/8 turn if needed.
A tiny turn can make a big change to the flow rate.
Tony
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