New (old) house, broken heating system

[jimsbrokenhouse]

Morning all, hoping someone can help me.


After years of renting we've just bought a house (1950s ex council semi) and I'm trying to wrap my head around the
heating system - I've only ever seen combis before, except my parents' old fully pumped conventional system - but
just can't work out what's going on.


The boiler is an old Halstead Best 40, the cylinder is the original from the 70s (heavily patched up with some
white stuff, must have leaked before) and there are the usual two tanks in the loft. The boiler has a 28mm out and
a 22mm (I think) in, connected to the central heating ring (according to the manual). The hot water in/out isn't
connected. The radiators all work fine (ancient microbore, I think 8mm, no thermo valves) but the cylinder doesn't
heat up - the input pipe doesn't even get warm. Currently using the immersion for HW, which is also ancient but
still works. There's one pump, just next to the boiler, and no motorised valves or anything else. Not even a room
thermostat (well, it's not connected). The controller is relatively new.


I tried disconnecting the pump and running it up to see if the tank heated up but unsurprisingly the boiler just
cut out after a minute of heating water that wasn't being taken away. There are two big red valves, one on the
cylinder output and one near the boiler, both are open.


We knew when we bought the place that the hot water didn't work and were hoping it would be a simple fix, but have
the money put aside to sort it if not. We've had a few blokes over but they've all been pushing to just tear the
whole thing out, radiators and all, and fit a combi. We can just about afford this, but don't want to tear the
whole house up and have to replaster/decorate the whole thing and live in a warzone for weeks.


So, questions are:
Do I have a pumped CH, gravity HW system?
Why is the cylinder not heating up when the CH is turned on?
Can it be fixed by draining down, power flushing and replacing the cylinder? If so, roughly how much will it cost?
Can we fit a combi and keep the microbore if it's flushed out?
Should we do that rather than keeping the boiler and replacing the cylinder/fixing the HW problem?
Or should we just suck it up and tear out the whole thing?


Thanks in advance - I know it's a huge post and probably not enough info to go on. I've gotten as far as I can
with my own research and getting people over but really not sure which option to explore!

 

[kris]

Hi there Jim and welcome along,,,, with what your describing I reckon it's all pumped as the boiler just cut off when you disconnected the pump, ( not good for boiler ).. If there's a time lock then you'll know if you've total control over the hw and ch, can you have ch on its own and if the time lock allows this then feel the coil pipes going into cylinder when on ch only if it doesn't heat up then there must be a motorised valve somewhere, if it does heat up then the time lock is basically acting as a switch when on does both, I think,,,

 

[jimsbrokenhouse]

Cheers Kris - I had to rewire the programmer (along with most of the electrics here it's been done by a chimpanzee and was an unsafe mess of taped mains cables hanging in a puddle behind the washing machine) which was what led me to realise that there was only one pump, one circuit (CH) and one set of pipes. No thermostat or valves anywhere. Running the CH doesn't heat up the pipe going into the cylinder, I assumed it's supposed to and there's a blockage somewhere. Looks like the minimum work then will be new cylinder, second pump, new HW piping and a power flush of the whole lot. For the amound of money and disruption we might as well seriously think about tearing the lot out and starting again with a combi :-S
Cheers again,
James