Low heat output

hardyannual · Posted: Wed Mar 07, 2007 12:36 pm Post Subject: Low heat output

I moved into an old house just before Xmas.During a cold spell the central heating did not seem to cope that well in warming the place up, although all the radiators did warm up. the one nearest to the boiler did appear to be the hottest.I was wondering if it might benefit from a new pump ? the Grundfos one has been marked with a date of 1992 . I have no idea how long they should last.

big-all · Posted: Wed Mar 07, 2007 12:50 pm Post Subject: Re: Low heat output

hardyannual wrote:

I moved into an old house just before Xmas.During a cold spell the central heating did not seem to cope that well in warming the place up, although all the radiators did warm up. the one nearest to the boiler did appear to be the hottest.I was wondering if it might benefit from a new pump ? the Grundfos one has been marked with a date of 1992 . I have no idea how long they should last.

heeelllooo and welcome hardyannual

the one nearest the boiler could be the last in the circuit therefore the coolest untill demand drops from the other radiators

you realy need to say what the capacity of the boiler and how many rads you have before somone [not me ] can work out if you have a mismatch

things to check though

that your boilers on full output and is running continuosly till the last radiator is up to or near full temprature

__________________
big all
we are------------------ all still learning

Agile · Posted: Wed Mar 07, 2007 12:59 pm Post Subject:

Grunfoss pumps can last 30 years if the water is clean so I dont recommend changing it.

You do need to balance the system and you should also see what condition the water is in. It should be clear and not noticeable blackish. A slight straw colour is OK though.

Tony

hardyannual · Posted: Wed Mar 07, 2007 2:54 pm Post Subject:

Hi
Thanks for the welcome and advice.

I'll open up one of the drain valves under the rads and check the water

first of all.

cheers

hardyannual · Posted: Thu Mar 08, 2007 12:08 pm Post Subject:

Further update.

I drained each valve under the rads - lots of black silvery water and for some reason quite foamy in places

drained until the water was clear in each case.

so will see how it goes

cheers

gas4you · Posted: Thu Mar 08, 2007 7:04 pm Post Subject:

Sounds like you have drained quite a lot out. I would suggest adding fresh inhibitor to protect system again

hardyannual · Posted: Fri Mar 09, 2007 11:21 pm Post Subject:

gas4you wrote:

Sounds like you have drained quite a lot out. I would suggest adding fresh inhibitor to protect system again

aarh hah is that what the foamy stuff was?

thanks, I had better get some

The heating guy at the old house told me to put it in the small tank every couple of years , but I never really knew where it was going.

JohnD · Posted: Fri Mar 09, 2007 11:26 pm Post Subject:

If there is lots of black, buy a bottle of chemical cleaner and use this first, then flush it out and refill using your inhibitor.

Sentinel and Fernox are good brands.

Read the instructions several times.