Dee Posted October 11, 2017 Posted October 11, 2017 I balanced my heating system a couple of years ago and all 15 rads worked perfectly but now some have ceased to heat up.... Cold at the bottom, Luke warm at the top. Pipes at TVR end are hot, pipes at lockdhirld end stone cold.... Any ideas?!
PeterW Posted October 11, 2017 Posted October 11, 2017 TRVs could be jammed. Take them off and see if the pistons on the valve heads move.
Nickfromwales Posted October 11, 2017 Posted October 11, 2017 41 minutes ago, Dee said: I balanced my heating system a couple of years ago and all 15 rads worked perfectly but now some have ceased to heat up.... Cold at the bottom, Luke warm at the top. Pipes at TVR end are hot, pipes at lockdhirld end stone cold.... Any ideas?! How old are the rads Dee? Quick test, turn each trv down to zero bar one of the troublesome rads. See if that heats through. It could just be the pump.
Dee Posted October 12, 2017 Author Posted October 12, 2017 All TVR are working.... Will try turning off and see what happens
Dee Posted October 12, 2017 Author Posted October 12, 2017 (edited) Should of mentioned this, The rads farthest from the boiler are the coldest... If one heats up what does that tell me? One is certainly now warmer at the top but cold at the bottom also some rads that I have 'turned off' remain very hot Edited October 12, 2017 by Dee
PeterW Posted October 12, 2017 Posted October 12, 2017 1 hour ago, Dee said: Should of mentioned this, The rads farthest from the boiler are the coldest... If one heats up what does that tell me? One is certainly now warmer at the top but cold at the bottom also some rads that I have 'turned off' remain very hot That tells me that the TRVs don’t work .... isolate the rad with both TRV and lockshield off. It shouldn’t get hot at all.
Dee Posted October 12, 2017 Author Posted October 12, 2017 @PeterW. I've long suspected the TVRs were dodgy but haven't got the money to change them.... Or skill.... Is there a cheats way of balancing the system? Last time I did it I was meticulous, measuring temp between pipes ect, took me the entire weekend!
dpmiller Posted October 12, 2017 Posted October 12, 2017 you shouldn't be using the TRVs for balance, just the lockshields and if they're not shutting down that certainly needs attending to firstoff.
PeterW Posted October 12, 2017 Posted October 12, 2017 You could get away with just changing the heads if the plungers still work. Take them off and give a squirt of WD40 and see if they move up and down. To balance you need to know the order in which they heat up - do you know the route from boiler to boiler ..?
Nickfromwales Posted October 12, 2017 Posted October 12, 2017 What type of boiler? Open pipe with a tank in the attic or sealed and pressurised ( aka system boiler ) with a filling loop and pressure gauge ? If the former, any pics of the plumbing by the pump so I can see if there's a bypass valve you can shut for testing? Dont pull the pins of the TRV's up too hard or you'll be needing wellies . They do come out with not much effort. ( and they don't go back in ask me how I found that out ).
Dee Posted October 13, 2017 Author Posted October 13, 2017 @dpmiller. I measured the temp across the pipes in each rad until the multimeter showed a variation of about 12 degrees and on the flow and return on the boiler.... I though that was correct? @PeterWall the plungers work fine, I don't understand why some rads shut down and others don't! I kinda know the route they heat up in but it's a big house and I get confused easily! @Nickfromwales It's a Heatrea sadia sealed system about 8yrs old. Pump seems fine although it gets extremely hot, hotter than the rads! Last night I turned all the rads off bar the coldest and furthest from the boiler, it did heat up but still warmer at the top than the bottom and when I turned about half back on it cooled down again... Go on what happened, you can tell me !!!!
PeterW Posted October 13, 2017 Posted October 13, 2017 @Dee Pump is shagged by the sounds of it. Get a new pump, or turn the current one up to max and do the test with the rads again. Sounds like it can’t circulate to all the rads properly. Have you got a Magnaclean in the boiler return flow ..?? That would help you see how much crud in the system and also re-dose the inhibitor. May be worth putting one in then dosing with X400 System cleaner and trying again ... one rad at a time ..! And if you can’t work the rads out then write on each one with dry wipe marker and it means you can just rub it off when you’re done ... TMV pins - are they loose or do they actually move up and down ..??
Nickfromwales Posted October 13, 2017 Posted October 13, 2017 X400 cleaner is for newer systems. I'd treat it with X800 sludge remover and leave that in for a month before draining, refilling and running for 48 hrs, then drain out and refill with 2x X100 inhibitors. It does sound like the pump is ( ahem ) shagged. ?? 8 years old for boiler AND rads? That's not old enough for the rads to be blocked with corrosion imo, but if never treated with inhibitor it's possible that they've furred up enough to warrant the X800 treatment. Drain down, chuck a new pump in and add the X800 when you refill. I'd also change the pump isolation valves at the same time as they will likely leak if you try to use them now. I always do that when drained down TBH as the buggers always leak soon afterwards and call-backs are a pita.
PeterW Posted October 13, 2017 Posted October 13, 2017 Worth putting the filter in before a clean down though @Nickfromwales as if the X800 does its job it will clog up the HeX on the boiler...? @Dee I would fit a Wilo Pico or similar as that will see another good 8-10 years on the pump.
Nickfromwales Posted October 13, 2017 Posted October 13, 2017 The heat exchanger is man enough to cope with the broken down particulate TBH, plus any existing crud in the HE will be broken down and made waterborne, hence the month of cycling prior to a full drain down, and refill with fresh inhibited water. Fitting the filter whilst fitting the pump would work, just you'd have to clean it every other day whilst the X800 does its thing. I'd run with the sludge remover first and fit the filter when it's empty from the second drain down after the X800 is spent.
Dee Posted October 13, 2017 Author Posted October 13, 2017 Two image of system and pump. How do I know if the pump is failing? It seems to run smoothly and silent... Never had any issues with it How do I turn it up and know that it isn't working too hard? Pressure gauge is set to 2 bar
PeterW Posted October 13, 2017 Posted October 13, 2017 Need a photo of the black box on the pump @Dee
Nickfromwales Posted October 13, 2017 Posted October 13, 2017 Or just is it on 1,2 or 3? This may be a motorised zone valve not opening properly / fully if it's a system boiler on S-plan. An you see the motorised valves @Dee ? Make / type? I can tell you the first checks to do then.
Dee Posted October 13, 2017 Author Posted October 13, 2017 HiTwo image of system and pump. How do I know if the pump is failing? It seems to run smoothly and silent... Never had any issues with it How do I turn it up and know that it isn't working too hard? Pressure gauge is set to 2 bar
Dee Posted October 13, 2017 Author Posted October 13, 2017 @PeterW. There is a dial on the black box with 3 settings, it's set to 3
PeterW Posted October 13, 2017 Posted October 13, 2017 Pump should be as warm as the rads. If it’s red hot then it’s blocked somewhere especially if it’s on 3. As @Nickfromwales said - any valves ..??
Dee Posted October 14, 2017 Author Posted October 14, 2017 @Nickfromwales Motorised valves? Can you describe what I'm looking for? ... Or should I get a plumber in? Thanks a gain
Nickfromwales Posted October 14, 2017 Posted October 14, 2017 58 minutes ago, Dee said: @Nickfromwales Motorised valves? Can you describe what I'm looking for? ... Or should I get a plumber in? Thanks a gain Something like these
Dee Posted October 15, 2017 Author Posted October 15, 2017 @PeterW. There is a dial on the black box with 3 settings, it's set to 3
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