Help - been told our current plumbing set up is all wrong

[SheRunsWithScissors]

Hello, Hoping PigletJohn, or another knowledgeable soul can help me out.

Had a plumber come out to see if he could find out why our boiler isn't starting up when it's meant to. Figure it's the heating controls, which he agrees. Getting an electrician over today to hopefully sort it out.

But, as he was checking out the system he said that we shouldn't have a pressurised cylinder, we should be on a sealed system.

We are in a four bed (fourth bed is converted loft with ensuite) semi-detached 1930s house. There is a small tank above the Megaflo cylinder, but only 15cm/6" above. We've been told it should be about 1m)

He mentioned that the current system will draw more air in. Which sounds plausible as we do have to bleed the radiators in the loft fairly often. More than normal for certain. The added air will also lead to quicker corrosion of the system.

Now, we had the compression in our previous cylinder (about a 20 yr old Megaflo) fail about two years ago. We had someone come out and replace the cylinder (different plumber to the one that came out this time).

If our system shouldn't be set up as it currently is, why didn't the other plumber identify this? Did the previous plumber not advise us well (no mention at the time of being on the wrong system) or is it more of a six of one/half dozen of the other type thing?

We aren't going to switch over at the moment anyway, as we've been told that although our current boiler should be fine with the switch over (old faithful thing about 15 yrs old) it may also fail and leak and need replacing.

If we do switch we are going to wait until we do a kitchen extension in the next 2 yrs and roll all the work together then.

So, my question is, are we on the wrong system?

Have attached a pic.

Thanks for reading this far!

I can't see all the pipework, but it looks like the black plastic cold water cistern is feeding the Megaflo.

You can do it like that, if the incoming water main has poor flow. It is not usual, but not a bad idea if you need a new cylinder, and plan later to upgrade the supply pipe. You will not get the best out of your Megaflo.

Fill a bucket at your kitchen cold tap (and the garden tap and the utility room tap, if you have them), time it, calculate how many litres per minute it delivers.

Then find you incoming stop-cock(s). There may be one in the kitchen and one in the front garden. Try to identify if the incoming pipe is plastic (black or blue), lead (grey) or iron (rusty) and whether it is as thick as your thumb, or greater.

Have you got a water meter? How old is the house?

There will be more questions.

p.s.

However, if the black tank is about 2ft x 1ft x 1ft then it will be to top-up the radiators and boiler, not the Megaflo.

This might be right or wrong. It depends what type of boiler you have. Does your boiler have a pressure gauge on the front? If so, it should be pressurised and will probably not work off a tank. If not, it should probably not be, and a tank is correct. The make and model, and some photos of the boiler, will help. Modern boilers are still made for open-vented systems, so the tank may be OK even if the boiler is brand-new. They are more prone to dirt, but there are methods to deal with it.

Hello, thank you for replying!!!

I can answer a few things now.

The boiler doesn't have a pressure gauge on it, old boiler, pic attached.

Can't fully measure the black tank as it goes in between two studs and is very heavily insulated around it. The width of it is 30", I'm thinking it can't be more than that on length based on where the wall it goes into ends.

We have a pump under the stairs on the ground floor to pump water up from the boiler (if that was explained to me correctly). This was replaced last year (photo also included for you viewing enjoyment).

It's hard to tell with the spiderweb of pipe work to see if the black tank feeds the cylinder. If it does, then it's a very circuitous route, using very narrow pipes.

Will check the water flow shortly I hope. I can say that we don't suffer from pressure at all, even in the loft shower. It's not a power shower /electric shower and doesn't have its own pump either. I know that's not what you asked though :-)

We don't have a water meter. House is 1930 semi detached.

Thanks again!!!!

Boiler pic, pipes and pump understairs on ground floor. Boiler is ground floor/kitchen.

The thin vertical pipe in the back of the photo is the one going out of the black tank that then joins a horizontal that then splits in two, then both go down... It's a tangle.

Sorry, the pipe joins the horizontal one with the two black top things (sorry, I'm usually good with building terms, just not plumbing). It comes up to them from underneath.

You have a Potterton Profile boiler. It is less efficient than a modern one, but don't chuck it out as the gas savings will not give you a good payback. It is an excellent and reliable beast. You might find the fan bearings wear out and become noisy. A new or reconditioned fan can be fitted. As long as parts are available it will last as long as you do. It does not need to be pressurised. It would be a good idea to have a system filter fitted on the Return pipe to the boiler. A competent boiler engineer will fit one with ease. You can then lay in a stock of Sentinel X100 and Z900. If you are in a hard water area, also X200 which will make the boiler quieter by dissolving limescale. These are DIY plumbing jobs but the engineer can do it. With luck you will clean the system enough with simple chemicals to improve its efficiency and avoid the need for a costly powerflush in future. Ask the installer to show you how to empty the trapped sediment from the filter. Ask him to look in that brass bottle-shaped thing to see if it is clogged with dirt and needs replacing.

The red Grundfos pump you show is to circulate heated water from the boiler to the radiators and to heat the cylinder. It has no effect on tapwater pressure.

If you get good pressure and flow from the taps and shower, then your Megaflo must be running off the mains, not off the tank, unless you can find another pump between the tank and the Megaflo. You would hear it running when you turn on the shower.

All those hot pipes should be lagged with Climaflex or similar, especially the ones between the boiler and the cylinder, and the cylinder and the taps.

Your installation looks like is a good-quality one that cost quite a bit.

You are brilliant. If I could give you a big hug I would :-)

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