Maintenance Plan for OFCH System

tm2204

I've an old OFCH system, old 15+ years boiler (F&E type not a combi), 13 rads, HWC with indirect coil, single zone (no motorised valves). Apart from annual/bi-annual service of the boiler I've not done much to the system apart from replacing the boiler circulation pump a few years ago.

I want to spend a bit of time (comfortable with plumbing) & money getting my system into shape as I'm almost certain I must have a lot of sludge in my system. Live in a soft water area so not so worried about scale. Some of the rads are starting to exhibit signs of sludge... colder at the bottom or patchy yet hot at the top.

Plan of action is as follows:

(1) Partially drain down the system, add a chemical cleaner (Protex Universal Cleanser from B&Q) to the F&E tank, turn water back on and let the system fill with the chemical cleaner (I've older type radiators so I can't feed the chemical cleaner directly in via any of my rads).

(2) Run the system for a couple of weeks. I'm hoping this will break down most of the sludge and get it circulating in the heating systems water.

(3) Remove each radiator individually (yes... time consuming), take outside and flush through with hose and/or powerwasher. Refit rads & bleed.

(4) Install MagnaClean filter beside boiler. This will involve fully draining down the system so I'll flush it through a few times with water from the F&E tank and let it run for a couple of hours each flush.

(5) Also while the system is drained I'll remove the boiler circulation pump and flush it through to remove any sludge built up.

(6) Final flush, refill & inhibit (Protex Inhibitor from B&Q).

A few people have suggested having a power flush done but I don't really like this... system is old and I do not want to risk blowing any seals or joints. Also it's costly and I don't mind manually doing each radiator myself.

I've watched a lot of YouTube videos (mainly PlumberParts & Dereton33) and I'm confident of doing this work myself.

Any suggestions or opinions on my plan? Thanks

tm2204

Any input on this? Looking to see if this plan is optimal or if there is a better way to go about it. Cheers.

K.Flyer

tm2204 wrote: »

Any input on this? Looking to see if this plan is optimal or if there is a better way to go about it. Cheers.

Yes, get someone in to give the system a good Power Flush.
With your plan every radiator connection you open you create the potential for a spillage and creating a mess. You also create the potential for leaks afterwards and your plan is excessively time consuming and not guaranteed to thoroughly clean the system.

tm2204

K.Flyer wrote: »

Yes, get someone in to give the system a good Power Flush.
With your plan every radiator connection you open you create the potential for a spillage and creating a mess. You also create the potential for leaks afterwards and your plan is excessively time consuming and not guaranteed to thoroughly clean the system.

Cheers for the reply. Being an old system having a power flush done concerns me exactly because it can cause leaks (high pressure on older seals & joints). also power flush is an expensive process. I have time on my hands so whipping off each rad (and replacing one or two with newer ones) and flushing through is no problem to me.

When you say "not guaranteed to fully clean the system"... can you elaborate? I am also installing a MagnaClean as part of this process so that's gonna catch the loosened sludge etc: after I run the chemical cleanser for a couple weeks. I'll also be inhibiting the system after.

WestWicklow1

tm2204 wrote: »

I am also installing a MagnaClean as part of this process so that's gonna catch the loosened sludge etc.

I've recently taken over the maintenance of my own central heating system. I never before heard of the MagnaClean. Thanks for informing me.

Do you think a MagnaClean, with regular maintenance of the MagnaClean itself, would eventually clean a 30-year-old system (10-year-old boiler)? I don't have any cold spots on the bottom of the radiators.

K.Flyer

tm2204 wrote: »

Cheers for the reply. Being an old system having a power flush done concerns me exactly because it can cause leaks (high pressure on older seals & joints). also power flush is an expensive process. I have time on my hands so whipping off each rad (and replacing one or two with newer ones) and flushing through is no problem to me.

When you say "not guaranteed to fully clean the system"... can you elaborate? I am also installing a MagnaClean as part of this process so that's gonna catch the loosened sludge etc: after I run the chemical cleanser for a couple weeks. I'll also be inhibiting the system after.

Whilst you are cleaning out the radiators and maybe some dirt out of the main circuit your method will not clean the arterial pipe runs between the main circuit and the radiators.
Also the danger is that loosened debris can get lodged in tight corners or valves causing bigger circulation problems for you.
A power flush machine will clean all parts of the heating system in both directions removing this risk.
The machine works by pushing more water faster, it utilises volume of water flow rates rather than high pressure.
A correctly installed Mag filter will prevent debris getting into your boiler heat exchanger but will not remove all of the dirt that has settled back down into the radiators from pipework that wasn't fully cleared.
The exercise is to remove all the dirty water from the entire heating system, including sediment in header tanks, leaving the system with fresh treated crystal clear water.

K.Flyer

WestWicklow1 wrote: »

I've recently taken over the maintenance of my own central heating system. I never before heard of the MagnaClean. Thanks for informing me.

Do you think a MagnaClean, with regular maintenance of the MagnaClean itself, would eventually clean a 30-year-old system (10-year-old boiler)? I don't have any cold spots on the bottom of the radiators.

It will pick up dirt suspended or floating in the water but it will not by itself disturb and remove dirt lodged in pipework or radiators.

tm2204

K.Flyer wrote: »

Whilst you are cleaning out the radiators and maybe some dirt out of the main circuit your method will not clean the arterial pipe runs between the main circuit and the radiators.
Also the danger is that loosened debris can get lodged in tight corners or valves causing bigger circulation problems for you.
A power flush machine will clean all parts of the heating system in both directions removing this risk.
The machine works by pushing more water faster, it utilises volume of water flow rates rather than high pressure.
A correctly installed Mag filter will prevent debris getting into your boiler heat exchanger but will not remove all of the dirt that has settled back down into the radiators from pipework that wasn't fully cleared.
The exercise is to remove all the dirty water from the entire heating system, including sediment in header tanks, leaving the system with fresh treated crystal clear water.

Thanks for the tips... appreciated.

Forgot about the header tank... I'll be cleaning this out as well

tm2204

WestWicklow1 wrote: »

I've recently taken over the maintenance of my own central heating system. I never before heard of the MagnaClean. Thanks for informing me.

Do you think a MagnaClean, with regular maintenance of the MagnaClean itself, would eventually clean a 30-year-old system (10-year-old boiler)? I don't have any cold spots on the bottom of the radiators.

I believe once you do an initial clean with a combination of power flush, chemical cleaner, magnaclean & header tank clean... flush through he system a few times then add chemical inhibitor on the final fill you should have an effective heating system. Check the magnaclean filter periodically to see how much sludge it's grabbing.

The fact you have no cold spots in your rads bodes well