Baxi WM 38/RS Manual

[markocosic]

Hello,


I've just bought a house, inside which is a geriatric Baxi WM/38 RS. The tag says that it's set to it's maximum heat output; house is 65m^2 1950s terrace with double glazing/cavity wall insulation/loft insulation. No idea when the boiler was fitted.

Controller is a Horstman H525; no thermostat. Hot water via vented cylinder, central heating via radiators plumbed in a 2-pipe system with TRVs all round. Pump is a Grundfos Selectric UPS 15-50 and there's a bypass valve fitted.

Previous occupants were muppets and set the heating to "on" 24/7 for both CH and HW; using the TRVs to "turn the heating off" so that they could heat the house with electric radiators/fans ("cheaper") but keep the hot water on - with the the boiler/pipework banging/clunking in sympathy. Shower is electric anyway.

I've opened all the lock-shields and set all the TRVs to a nominal 21C; set the CH for 06:00-08:00 and 20:00-23:00; HW for 07:00-08:0 and 20:00-21:00. I've dropped gallons of water out of the system/flushed with gravity, and bled the rads. Less banging/clunking, but still non-zero. There's the clunk-clunk of badly installed pipes expanding and contracting, plus kettling from inside the boiler.

Flow and return pipes are roasting hot. I appreciate that this isn't a condensing boiler and it will have a bloody hot return, but the dial on the front of the boiler that runs from 1-6 doesn't appear to do an awful lot.

Should it?

Are there user manuals available? (beyond what's printed on the back of the front cover)

Is it worth attempting to descale the heat exchanger with an acidic descaler?


Above the boiler are soot marks, though it isn't tripping the CO alarm in the kitchen, so these could be from a previous life.

Any there servicing manuals available?

Brushing the heat exchanger fins would appear straightforward, but looking through the pilot sight glass there's some white crust around the holes/slots in the burner tube/whatsit that the flames appear out of.

Any RGIs in the Cambridge area willing to:

-loan me the brushes one evening
-recommission the boiler (check supply pressure/for leaks/exhaust gas readings)

I'm happy to do the monkey-work of dismantling/cleaning/reassembling (it's a pretty simple boiler) but I don't have the gear to recommission it and it'd be easier to clean the fins with the proper tools.

In 18 months or so it'll get replaced, but I'll need another winter out of it for now.


Thanks,

--
Marko

 

[buck51]

Some people will never get the message!!!!

 

[markocosic]

Outrageous isn't it, asking for a service manual and an RGi with pressure gauges/sniffer.

Pulled the HX cover, cleaned the thermostat bulb and its hole with scotchbrite, added a dab of heat transfer paste and reassembled - appears to have done the trick.

Still interested in somebody local with gauges/sniffer to check that side of things.

 

[CBF]

buck is not talking about you asking for the MI they are saying you shouldn't be doing anything to the inside of the boiler you are not a RGI

 

[markocosic]

That the problem. I'm new to the area and tried a few umbers from the yellow pages but gave up hope of finding somebody able (willing?) to understand English let alone repair a boiler.

"Can you service X?" "No mate, what you want is..."

Best to replace said boiler immediately, regardless of reasons for delaying until house is extended/re-plumbed in its entirety.
Impossible to service something so old, parts not available
Regs say you're not allowed to service something so old
Regs say that an RGI is needed to wipe the dust off the outside of the case nevermind touch the insides
Regs say I can't just sniff and pressure test it for you
Regs say that you need a condensing boiler these days yada yada

But if you want me to nail a new combi on the wall for you then that'll be...

I gave up after double digits of full of it/themselves. Welcome to the southeast eh!

 

[FiremanT]

Ditch the YP's. Talk to a neighbour and get a recomendation. A full service o that boiler will be less than a ton.

 

[Tibbot]

Welcome to the southeast

Cambridge is in Anglia, not South East.

 

[markocosic]

It's south of Watford Gap as far as rates go!

Ditching the YP and waiting for an RGI doing some work on a nearby council property to earn himself a drink on his lunchbreak did the trick.

(all ok)

 

[skodaman007]

www.partsarena.com/baxi/

follow any download instructions (grafix viewer)

then find your Baxi Wall Mounted boiler.

 

[markocosic]

Awesome; thanks!