Back boiler, hot water dirty

[MrMrMr111]

I don't know much about central heating. We have a back boiler behind the gas fire in living room.

I also have some form of water tank in the loft, I believe this to be the hot water tank? As we can only get about 3/4 of bath full of hot water.

The heating control we have allows you to only have hot water on, but if you press heating then both the hot water and heater control LED goes on. Beside the fire is a small cupboard that has a pump which is for the central heating to pump hot water around I presume.

Few questions...

Why is the water running dirty now. I've drained tank (switched on not water tank till no more hot water).

How do I top up the central heating system? It's years old now and have to say has had to maintenance really, never been flushed etc. we are getting quite a few pipe gurgling and banging now, I'm presuming this is air in system? That's why I want to top it up.

I know really it needs a full service as such, flush out, but the house is up for sale so don't really want to spend too much.

Cheers

 

[dcawkwell]

If house is up for sale wouldn't worry about it.
It will soon be warm enough to heat the hot water with the immersion and switch the boiler off.
Get it sold over the summer and away you go.

You've probably drawn dirty water in from the header tank into the hot water tank if you drained it. It will run clear again.
Other possibility is you have a leak from the central heatin via the coil in the tank into the hot water. So you get directy central heating water into the hot water. New hot water tank time.

 

[Hugh Jaleak]

Sounds like system is sludged up, but I would check the water level. Look in loft space, should find two cisterns, (tanks). Larger feeds the hot water cylinder, ignore that. Smaller will be the 'feed and expansion' cistern, serves the CH system. Check it's got water in it. (Will probably be filthy water but dont worry too much at this stage.)

If the F&E does contain water then possible the feed from this into the tank is blocked, can try draining some water off from a drain off, and see if system tops itself back up. If level doesnt move in F&E cistern the possible cold feed from the cistern to the system is blocked. Need to trace affected section of pipe and replace it. (Run a magnet along the pipe, any build up of crud will attract the magnet.)

Running the system with low water content at best wont do it any favours, at worst could be dangerous. Appreciate you're selling up but if heating system is found to be knackered then could affect asking price...

 

[SmithyXL]

An old system as you describe and only one tank in the loft-space? could suggest a primatic cylinder, bit awkward to work on for a DIYer, I would get someone in to have a look and confirm the problem for you. best of luck with it.

 

[MrMrMr111]

Thanks for ideas. I'm going to have to go in loft and have a look and report back aren't I. Looks like my Easter w/end is taken!?! I'm sure I've only got one tank, seem to remember it just being a square tank and had a loose top/cover on it and could hear water being poured into it, filling.

Regarding leaving it as its selling, I would but the house has been up for a few years now and nothing so I can't risk leaving it too long.

For some reason the downstairs hot tap didn't used to be dirty really always the bathroom hot tap upstairs. But now the downstairs is really dirty to. I was hoping after a few days it wood run clear but this time seems to have stopped dirty.

Should I try a cleaning fluid? Any recommendations? Also where don't pour it in?

Cheers

 

[Hugh Jaleak]

Need to ascertain how many tanks you've got in the loftspace. If there's only the one, then chances are you may have a 'Primatic' cylinder as SmithyXL suggests. Unfortunately if this is the case then there's no chance of getting any cleaning fluid into the system, and the design of the cylinder may well be the root of your problems.

Gurgling and banging well well suggest boiler is overheating, which could be a result of a gunged up system. Unfortunately, with a Primatic cylinder, there is no opportunity to add chemicals to the system, so protection against corrosion cannot be introduced, so system begins to suffer electrolytic corrosion from day one.

Think it's going to come down to what your prepared to pay out to get it sorted against what you are prepared to lose from the asking price when selling...

 

[MrMrMr111]

Well I believe I'm right in thinking if I sell it as is, there's never any guarantee of the heating, electrics anyway is there? (In UK?). I'm not trying to "get away with it", I'd rather have it working fine to be fair but don't want to spend too much at all. To be honest if we were stopping I'd replace it all with a combi and new radiators, but this won't get reflected in the price back is get so I'm prepared to try and struggle on until it sells.

I'll have a look over the w/end to see what tank/cylinder I have and report back.

Thanks again

 

[Hugh Jaleak]

No guarantee possibly, but if it gets picked up by a keen surveyor then that gives any prospective buyer ammunition to start negotiating price reductions. If the existing system can be 'nursed' back into life for a reasonable price then maybe better than a buyer wanting several £K off the asking price in order to fit an entire new system.....

 

[keego]

I'm sure I've only got one tank, seem to remember it just being a square tank and had a loose top/cover on it and could hear water being poured into it, filling.

Sounds like a Rolyat, if you're still getting dirty water then it's fooked & you would need to replace with a Fortic F3 & fit a separate F&E tank which ain't going to be cheap!

 

[MrMrMr111]

I'm sure I've only got one tank, seem to remember it just being a square tank and had a loose top/cover on it and could hear water being poured into it, filling.

Sounds like a Rolyat, if you're still getting dirty water then it's fooked & you would need to replace with a Fortic F3 & fit a separate F&E tank which ain't going to be cheap!

Oh dear this sounds expensive. How much are we talking? Is it a DIY job?

 

[keego]

If it is a Rolyat or similar ( it would look like a tea chest ) then you are looking at a day's labour, about £250 plus parts, it's not a DIY option. Bearing in mind you have a BBU then it would be more economical to do a combi conversion.
If you've just put the house on the market the doing this would make it more sale able, however if you've got a buyer then think how you would feel if you had been shat on in the same way, the last thing you need when you've just moved house is a huge bill......it's your conscience & if you can live with it then so be it.

 

[sooey]

But he said

I'm not trying to "get away with it",