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Plumberpro, Mechanical Engineer
Category: HVAC
Satisfied Customers: 634
Experience:  Over 20 years experience in plumbing heating and gas
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I have a Ideal 535Classic Combi boiler2 Honeywell CM707

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I have a Ideal 535Classic Combi boiler
2 Honeywell CM707 RoomThermostats - 1 in upstair bedroom -1 in lounge
New build house - moved in June
Problems -boiler cuts on /off before Room temp is reached as does the room thermostats
eg - time tRoom temp 15.5 room temp set to reach 20c
Time 4.54 boiler on
time 4.56 boiler off but calling for heat. the boiler clicks on /off unti 6.05 when the room temp reached 19c when the boiler displayed 0 1 min later it went on then off and every few mins it was 6.59 before 20c was reachedI am now told to put ALL the trvs open to 6 for boiler to work - yet the room stats goes off and boiler before temp is reached - please help. rads were recluctantly balanced for me
Customer: replied 2 years ago.
(Posted by JustAnswer at customer's request) Hello. I would like to request the following Expert Service(s) from you: Live Phone Call. Let me know if you need more information, or send me the service offer(s) so we can proceed.
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Customer: replied 2 years ago.
Hi I am a pensioner with very limited income - I have already paid £29 and to pay an extra £8 is beyond me I have not received a reply to my question so can only rate 1 star
Hi, we can continue to talk like this, if you like. It definitely sounds like there is a flow issue. Which could be from a pipe work problem , incorrectly installed, undersized . Or could be an issue with the pump( not running at full power ). . The reason that your room stat isn't reaching what you've set it at, could be that boiler is getting up to temperature too quickly due to Decrased flow rate...The other alternative is that the temperature sensor in the boiler May be faulty and is not letting the boiler get hot enough
Customer: replied 2 years ago.
Thanks for this. Flow issue - which pipe work please, there is a new pump on boiler. when the Ideal boiler guy came outhe said that the temp in oiler was 75c 9If I remember right) and the rads were 56 at top and 48 at bottom. when the plumbing boss came on Fri he said you do not want the rads at 75 as that can scald you !!! According to him All the Trvs have to be FULLY open at 6 for the boiler to work properly I questionthis
Customer: replied 2 years ago.
PS with the rads open fully at 6 the room temp reaches quicker but after a few hrs the thermosts asks fo the boiler to go on again but its only on for less than a minute
Hi , the scalding thing is rubbish. Most heating systems are designed to run at full temperature. You should be gettingn g the radiators at at least 70 if the boiler is getting to 75 degrees.. the ttc s don't all have to be fully open , thatsco poets rubbish too , otherwise what's the point of them . There whole purpose is to allow individual room temperature control. You should have 22mm pipework from the boiler and out as main branches of heating pipework. I so see if they have run it in 15mm pipework to cost save
Customer: replied 2 years ago.
Thks for all this . just because I am an OAP .- woman on my own - they are tryn to fob me off with technical data. I did say to him what is the point of having 2 thermostats if they all have to be (a) fulyl open at 6 to work and (b) upstairs and down stairs on at the same time. he told down stair heat was escaping upstair.
the other thing that happens is the pumps that work heating - when the thermostats go off you can hear a noise coming from the pumps until the boiler goes off - yet when u run the how water and the fan of boiler is on here is no noise from these. I am willing to pay the extra £8 if you are not understanding all my questions. but I would like something in writing so that I can show these plumbers hat the problems could be - I have no idea how much info I can get for £29
When the heating goes off , often the boiler pump will continue to run for a Couple of minutes to clear heat from the boiler. I would recommend an independent report from a heating engineer who can come out and have a look for themselves
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Customer: replied 2 years ago.
Thank you for all this - I do not think Persimmon will be too happy to pay for an independent heating engineer but I shall put I to them - thank you for you your advice - I rate U 5 STAR