Central Heating inhibitor/injector

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Daynat

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Feb 17, 2016
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Location
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Hello guys

Some time ago I would buy CH inhibitor with a fixed connector already attached. Cannot seem to get one anywhere now.

I do not fancy paying £12 or so for a little bit of plastic nozzle. I wonder if anyone has ever made up their own ?. Any advice please.

Thank you

Daynat :D
 
"Hello Daynat",

Do You know that this is a U.S. Plumbers Forum ?


The Plumbers on here might suggest something / fittings to use when adding Heating system chemicals [Cleanser / Corrosion Inhibitor etc.] however they might not be aware that You want to connect to the top tapping on a Radiator or Combi Boiler filling loop - and You might not be able to buy the item in the UK.

IF You mean a method to POUR Inhibitor etc. into the top of a Radiator [1/2" Vent or Plug removed] you could use a Funnel and you could make up an `L shaped` pipe [soldering] using:

A piece of 22mm Copper pipe - 22mm Elbow - 22mm to 15mm Internal reducer - short of 15mm Copper pipe and a 15mm x 1/2" Compression Male Iron to Copper.

Screw the Male Iron to Copper into the 1/2" tapping at the top of the Radiator - connect the L shaped pipe - then use the Funnel [end size to fit into the top of the 22mm upstand] to pour the Chemical into the Radiator.

Obviously You will have to isolate the Radiator and have drained enough Water out of the Radiator to accommodate the Corrosion Inhibitor / System Cleanser before pouring in the Chemical.

But if You want an inexpensive `Kit` which includes a Plastic Radiator adaptor / Bottle adaptor and short of plastic hose pipe here is one from ebay:


http://www.ebay.co.uk/itm/No-Nonsense-Central-Heating-Filling-Kit-By-Plumb-Sure-/191980009267


I am assuming that You do NOT mean the Fernox [and other manufacturers] Concentrated Inhibitor which comes in a Mastic gun tube and has a small flexible tube which screws into the Radiator Vent plug pinhole ?



I have assumed that because You mention `not wanting to pay £12.00 for a plastic nozzle`.

And as You will know the Fernox type Concentrated Inhibitors cost a `Premium price` which can often be more than double the price of Heating Chemicals supplied in plastic bottles.


I hope that these suggestions are helpful.

Regards,

Chris
 
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If I wanted to inject chemicals into a hydronic system.

i would make a pot feeder.

"Hello Frodo",

The OP / Daynat mentioned that He did not want to spend even £12.00 [$14.64] on an item to connect to a UK Heating system [I am guessing a Domestic system].


The `L shaped pipe` that I suggested making up would be from fittings that any UK Heating Engineer or Plumber would already have - but even if they had to be bought would only cost about £2.00 [$2.44] - not including the small pieces of 22mm & 15mm Copper pipe [Offcuts].

Also IF He intends to be connecting to the top of a Radiator - removing either the 1/2" Vent or Plug - having isolated the Radiator and drained out enough water to accommodate the Chemical - there is no need for any Valves on the pipe that I described as the Chemical would just be being poured into a partially drained Radiator.

I mentioned in my previous message about a type of Heating system Corrosion Inhibitor which comes in a Mastic gun tube - that has a thin flexible plastic tube which screws onto the Inhibitor container [Mastic type tube] and into the pinhole of a Radiator Vent plug - adaptors can be obtained which enable that small flexible tube to be connected to the `Filling Loop` 1/2" Stainless steel braided hose connection on a Pressurised Heating system / Combination Boiler.

As I noted in my message to Daynat - those particular products are priced at a `Premium` because of their `Ease of use` and are often more than double [perhaps treble] the price of Corrosion Inhibitor / System Cleanser etc. that is supplied in Bottles.


However I am sure that your suggestion of making up a `Pot Feeder` works perfectly well and is cost effective for the Heating systems that you deal with.


Regards,

Chris
 
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Oh! Many thanks for all the useful information supplied.
I just hate spending money for over-priced goods, and often make up my own rudimentary tools. Does the job.
I did make up some pipe-work using the method described, but did not think of using the 15mm X 1/2" iron to copper compression. So it did not work efficiently.

Many thanks again.

Daynat
 
be careful when you drain the radiator as others have advised, if you introduce air into a closed system .you risk getting an air lock at a high point

"Hello again Frodo",

I assume that you were referring to my comment about draining an amount of system water out of a Radiator in order to pour in Corrosion Inhibitor.


Here in the UK the process that we use is:

Turn Off the Heating system.

Turn Off the Radiator Valves at both ends of the Radiator - noting the amount of turns to close the Lockshield valve [the Return valve] - to be able to reset it for Balancing the Flow / Return rate.


Loosen one of the Radiator Valve unions and drain out [into a container / tray while venting the Radiator] an amount of system water which is slightly more than the amount of Corrosion Inhibitor that is going to be poured in.

Remove the top Plug [ideally] or Vent [if necessary for access] from the Radiator and connect a `Funnel Adaptor` & Funnel [as I described in my previous message] or a similar adaptor - and pour in the Chemical.

Remove the Adaptor connection and replace the Plug or Vent plug.

Turn the Radiator Flow valve - Vent the Radiator until full - on a Sealed system that will require Re-pressurisation of the system - possibly while refilling the Radiator depending upon the Volume of water in the system but if not - afterwards.

Turn on the Lockshield valve [Return valve] - set at the number of turns that you noted when turning it off - re. the Balancing of the Radiator Flow / Return rate.

Turn on the Heating system and run to circulate the Corrosion Inhibitor or other system Chemical.

Carrying out the process in that manner will NOT cause any `Air Lock`.


Many Domestic Heating systems in the UK are `Open Vented` - with a Feed and Expansion Tank.

Others are `Sealed Systems` / Pressurised systems which are filled from the Mains water using a removable `Filling Loop` braided hose in order to remove the connection when the system has been filled / pressurised - there is obviously a double check non return valve on the connection to the Heating system pipework.

The process that I describe above would NOT allow any `Air` to be introduced into either type of system except for the Oxygen content in the very small amount of `Top Up` water - that Oxygen is negated by the Corrosion Inhibitors that We use here as part of the Corrosion Inhibiting process.

Also when installing Open Vented Heating systems in the UK we don`t allow any `High points` without an Air vent - with Sealed / Pressurised systems that is not as crucial although `Good System design` is still necessary.

Chris
 
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"Hello again Frodo",



Turn Off the Heating system.

Turn Off the Radiator Valves at both ends of the Radiator - noting the amount of turns to close the Lockshield valve [the Return valve] - to be able to reset it for Balancing the Flow / Return rate.


Loosen one of the Radiator Valve unions and drain out [into a container / tray while venting the Radiator] an amount of system water which is slightly more than the amount of Corrosion Inhibitor that is going to be poured in.

Remove the top Plug [ideally] or Vent [if necessary for access] from the Radiator and connect a `Funnel Adaptor` & Funnel [as I described in my previous message] or a similar adaptor - and pour in the Chemical.

Remove the Adaptor connection and replace the Plug or Vent plug.

Turn the Radiator Flow valve - Vent the Radiator until full - on a Sealed system that will require Re-pressurisation of the system - possibly while refilling the Radiator depending upon the Volume of water in the system but if not - afterwards.

Turn on the Lockshield valve [Return valve] - set at the number of turns that you noted when turning it off - re. the Balancing of the Radiator Flow / Return rate.
it is called a balance valve,/ circuit setter hash marks and a screw lock
Turn on the Heating system and run to circulate the Corrosion Inhibitor or other system Chemical.



Chris


To much work,

turn off the petcock valve under the bleeder, remove the bleeder
screw on the pot feeder
fill pot feeder, turn off the top pot feeder valve open the lower valve
let it sit and the water will circ thru the heater and pull the chemicals into the system

when finished, turn pet cock valve off unscrew feeder, screw bleeder back on.
turn pet cock on

drink a pint

btw, air lock does not happen just at high points
it can happen any where bubbles accumulate

Bell_and_gossett_circuit_setter_balance_valve__52845__25376__58068.1369873471.1280.1280.jpg balance valve/circuit setter/ test ports


w_1_0026231_dahl-521-51-61-14-fip-x-14-mip-lead-free_300.png petcock/gauge cock
 
To much work,

turn off the petcock valve under the bleeder, remove the bleeder
screw on the pot feeder

fill pot feeder, turn off the top pot feeder valve open the lower valve
let it sit and the water will circ thru the heater and pull the chemicals into the system

when finished, turn pet cock valve off unscrew feeder, screw bleeder back on.
turn pet cock on

drink a pint

btw, air lock does not happen just at high points
it can happen any where bubbles accumulate

View attachment 13259 balance valve/circuit setter/ test ports


View attachment 13260 petcock/gauge cock


"Hello again Frodo",

You are missing the entire point of this thread - seemingly just to argue with Me - this thread / original question was NOT `What is the best way to introduce Heating system Chemicals into systems ?`


Daynat / the OP wanted to be able to add Heating system Chemicals by making up an `inexpensive adaptor` - I guessed correctly that He wanted to be able to POUR IN the Chemicals and I described a simple / inexpensive to make `Funnel adaptor` - He was advised by Me how to do EXACTLY what He wanted to do.

Radiators in the UK and most of Europe do not have any `Petcocks`.

In order to connect ANYTHING to the top tappings on a Radiator [while the system is full of water] it must be isolated by turning off both Radiator valves and at least a small amount of system water drained out of the Radiator before removing the Plug or Vent Plug - unless one does not mind getting the Floor / Radiator and Valve wet.


Because of that point the OP / Daynat would just drain out a little more - just over a Litre / 2 UK Pints would usually suffice - and carry out the procedure that I described - which is exactly what He wants to do.


I am NOT stating that this is the `Best way` or that I or my Company`s Heating Engineers would go through that somewhat `time consuming process`.

We `Inject` the Chemicals in probably less than 2 minutes using the `Mastic Gun type container / tube` that I previously described.


We also use Aerosol Corrosion Inhibitors which Inject the Inhibitor in seconds.



As far as I recall YOU brought up the subject of `Air locks at High points` when you were trying to criticise the process that I explained in a previous message ?


The Air / Oxygen bubbles in the Fill water / Top up water are negated by the Corrosion Inhibitor Chemical - that is one of the `Main jobs` of the Inhibitor.



Chris
 
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