Wt Heating Oil Discussion Threads

[equaliser] 29/7/2002 00:20

edit double post

[equaliser] 29/7/2002 00:18

Paulismyname

A few questions on your old Potterton system, as 5 years is not a long time
and from my experiance Potterton are reliable I still run a 18 year old system on a wall mounted Poterton 50k BTU.

Your statement that the pipe work is too small and the Boiler overheated ?

1 Boilers have internal thermostats to regulate heat exchanger thmperature, so even considering less than ideal water flows the boiler should not self destruct. The only outcome would be poor heat flow into water and a bit of wasted gas heat input ( wasting a bit of money)

1a Have you had the pump cheched ?

2. Was this boiler a cast iron heat exchanger type.
3. was the system fully pumped or pumped heating & gravity Hot water a new instalation 5 years ago would be fully pumped if it is 15 years + then graverty.

In short it does not sound that you need a complete new system but a new cast iron boiler simple and robust cost for 60,000 BTU should do a large house
less than 500 pounds from Wickes Halstead boilers make them for wickes so check their web site for larger units if needed. cost more direct though.


I agree with the others that you are in for a rip off if not carefull

you should be able to sort this for 800 to a grand without tearing up the house.

Yes it would be nice to fit a new system in which case condesing combi boilers
could be considered but new radiators and thermo valves will be needed as well.

Something else you will hear is a recent change in building regulations that now insist that, if a heating system is replaced then it must conform to a energy eficiency standard.
This has a lot of issues on boiler control ( this hits gravity systems but not fully pumped. and you need thermo rad valves. you may need an instaler who is willing to ignore this or DIY

My view, to control expenditure and get value for money a cast iron boiler fully pumped and a few rad valves should do it. but if your system is gravity then some changes to pipes might be needed.

Good luck.

[paulismyname] 29/7/2002 00:15

Thank you very much for all the pointers posters, I certainly take on board the dual issues of qualified engineers and BG overpricing. I will post again when a solution has occured

[paulismyname] 28/7/2002 21:45

I am very grateful for some of the informed comments posted here, please do not allow me to take your time from active trading but to answer some requests for more infomation:

a) Boiler is a potterdon 850 BTU

b) The is a three way valve in the airing cuboard upstairs on the other side of a largish double fronted victorian house split bu a staircase

c) It is a microbore system.

d) Do not know what type of pump I have

e) I can control the temperature of the water in the rads by a dial on the boiler, the temp of the water in the airing cuboard by another dial fixed to the hot water tank, and the governing temp of the overal house by an air thermostat in the hall downstairs

f) there are two additional tanks in the loft.

g) We did have the system drained out and new "salts" put in it a year or so ago

h) there are 10 rads, most of which are double.

i) original pipework was done before we moved in, say about 20 years ago

j) Have had a new pump three years ago together with a 3 way valve

[equaliser] 28/7/2002 18:43

Paulismyname

There are interesting technical ideas developing here can you provide more details on 'not working' Does the boiler try to ignite, does the circulation pump run. What do you see hear when you switch on.


Thinking on it further the idea that a combi can cope with higher pressure is a bit naff as the circulation pump is the same Grundfoss thpe as used in all systems.
circulation pumps can rust up and this is not always obvious.
there is often a 3 position switch on the side of the pump 1 slow speed 3 fast speed.
a tall/large house ie victorian would need to be set to 3 to lift the water and get flow rate through a long pipe network. Pumps come in various capabilitys in terms of flow rate and lift head. there is a graph supplied with new pumps which gives these values for the pump's settings.

DSS's ideas on control valves is worth going into. idealy you need a central heating engineer who will fix your old system and it could be a simple fault even a blown fuse. Unfortunately all you too often find is the "you need a new system mate" central heating fitters who want to fit combi's as they are easy to install but as others earlier told you have issues. I say this as in my house fixing up game I fit combi's myself then get the safety issues inspected as FSE said earlier.

Eq

[dss] 28/7/2002 15:40

One of the most regular faults on a system which our guys go out to, apart from the thermocouple ,is the failure of a valve,either 3 position diverter on such as a y plan system or more likely on a big house system a port valve for the upstairs and down stairs.

Do you have more than one thermostat?

can you time heat upstairs and down seperatly?

The port valves will be probably near to the boiler at a point where upstairs diverts away from downstairs.It will be controlled by either time,a stat or both.
It will have a short shiny flex leading away from it and probably a makers plate of Honeywell or Danfoss.It is a silver box 3"*2.5"*2" and appears to be attached to the pipe almost like a Limpit (or is it a Limpet!)

If it is faulty it will be hot at one side and cold at the other as the pipes lead into it.The result of this having failed is that you boiler is basically trying to push hot water into a "brick wall" since the valve is a very efficient stoptap when closed.

[blueflame] 27/7/2002 13:07

double post.

[blueflame] 27/7/2002 13:00

FSE - Not to sure I would promote fitting it yourself. A guy in Nottingham fitted it himself and the HSE prosecuted him and he got sent to Prison for 6 months. Be careful.

Paul..... Unless your 10mm pipe is seriously scaled or sludged up I wouldnt go to the expense/problem of ripping it all out.

Baxi's new Combi looks very good and they have had few reliabilty issues with the latest one's. Dont touch a Baxi Bahama though.

[jeffmack] 27/7/2002 08:31

Had a potterton combi boiler fitted yesterday and it doesn't work. Now have towait for the Potterton engineer to come out tomorrow. Cost including some new controls on my tank, £1500

[the wah] 27/7/2002 08:23

Paulismyname, much good advice above.
I had a new condensing boiler fitted to my old house, using the existing plumbing and hot water tank,adding four extra radiators and fitting the necessary motorised valves and thermostat. I had quotes from British Gas and two local firms: BG- £5k, local#1- £3k, local#2- £1.8k. The cheapest was recommended by a neighbour, so I knew that their work was OK. I went along with BG at first because they were offering a 5 year guarantee and low interest, low deposit credit. They turned me down for credit,(because my old address had not been registered by the landlord with the Post Office as it was on his existing property), I therefore told them I didn't want to go ahead. Despite this, their poor subcontractor turned up unannounced some weeks later with all the hardware on his van ready to start.
I also via Uswitch, try your search engine, I will edit in the URL later, changed my gas and electricity supply to who deal with you entirely online, and compared to BG and Npower are saving me about 25% on my bills, (the condensing boiler saves even more). Uswitch may recommend a different supplier depending on your consumption pattern.
regards, The Wah

[i know nothing] 26/7/2002 23:25

Paul,

Just fitted a 80,000 BTU Combination boiler for £800 including labour. Changed one radiator (cost about £25 only a small one) and five TRV's (Thermodtatic Radiator valves, decent quality) which were approx £15 each from B&Q, this I did myself as the plumber had drained the system down. It took me no more than 1 hour to complete this task. He spent the morning changing the boiler and the afternoon charging (and flushing and adding new chemical) the system.

The combination boiler is 20,000 BTU more than what is recommended, why? because a 60,000 BTU boiler would not heat enough water for the shower quick enough. For an extra £150 I wanted the bigger boiler. System works a treat and I'm very happy with it, would have no problems recommending such a system. Boiler is made by Bosch (doesn't show Bosch on it, different name, but part of Bosch Group). I did have to add a thermostatic valve (preferable over a pressure reducing valve) to the shower, cost about £175, again beware, some people will try and sell these for £350, find out what you need and go to a Builders Merchants for one.

So all in all, I would say that £3500 is a con. I would take issue with one point you raised concerning the pressure of hot water from a combination boiler, they restrict flow, so pressure may remain constant but you get less of it, watch out for that one, that is the sole reason why I opted for a 80,000BTU boiler, to get the increased flow rate.

IKN

[rysiu] 26/7/2002 23:04

Have had a quote from from an employee (just handed in his notice to go into business on his own) to remove old boiler, cold/hot water tanks and all pipework - new boiler a Worcester with nine radiators and 8 controlling valves, total cost £2,600 which I have been told by a professional ex=plumber that it is correct. Says that British Gas always price these jobs £1K more in view of all the checks they do after connection - i.e. Supervisor, Manager etc. etc.
Syas he will complete the work in four days.

[lastmanstanding] 26/7/2002 23:02

Get afew different people to come in and give you costing before deciding.

NEVER BUY FROM THE FIRST SALESMAN. A lesson you will do well to learn.

good luck mate.