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Flowmeter and glycol
We have just had our Valiant ASHP serviced and the report has come back that we only have plain water in the circuit and we lack a flow meter.
Do we need both glycol and a flow meter (if so our bloody useless installers have mucked up yet again) if not why are they recommended by the servicing team?
At around £800 it more bloody remedial work on this installation.
Cheers
Mark
Posted by: @witchcraftWe have just had our Valiant ASHP serviced and the report has come back that we only have plain water in the circuit and we lack a flow meter.
Do we need both glycol and a flow meter (if so our bloody useless installers have mucked up yet again) if not why are they recommended by the servicing team?
At around £800 it more bloody remedial work on this installation.
Cheers
Mark
You should not need an additional flow meter. The ASHP should have a flow rate sensor which is enough for normal use. This will throw an error code if the flow is too low. I have an external flow meter but this is for MMSP monitoring. You should ask the engineer why a flow meter is needed? Maybe they are just fishing for work?
The system would normally be filled with a glycol mix on commissioning. If not, anti freeze valves are an alternative. If you have neither then there is a risk that if/when there is a power cut and it's very cold the ASHP could freeze up and be damaged. Unfortunately it's quite an expensive job to refill with glycol.
Posted by: @witchcraftWe have just had our Valiant ASHP serviced and the report has come back that we only have plain water in the circuit and we lack a flow meter.
Do we need both glycol and a flow meter (if so our bloody useless installers have mucked up yet again) if not why are they recommended by the servicing team?
At around £800 it more bloody remedial work on this installation.
Cheers
Mark
I would suggest that you ask your installer to add the glycol that they should have added during the installation. If they refuse then make a complaint to MCS and any other body who have supposedly accredited their service.
Posted by: @witchcraft@derek-m But these installers are the lovely mob I took to court and they then went bust
They should have indemnity insurance against which you should be able to claim.
@witchcraft, your MCS installers will have been insured by HEIS or another body. It’s a requirement and it’ll be in your paperwork.
On the subject of glycol, it’s usually added in systems to prevent accidental freezing in the event a heat pump stops working or if there’s a power outage. Most installers add it to be “safe”. I’m not sure it’s a requirement though.
I’m with Kev on the flow meter. The pump should have this built in as it cuts out when there’s insufficient flow. Surely Vaillant heat pumps have their own flow sensors without the need for additional external ones.
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You don’t need glycol or a flow meter….
glycol is just a terrible solution to the ‘power cut in the middle of winter’ problem…. Caleffi anti freeze valves are £150-200 a pair, Chinese ones are £40 a pair.
Off grid on the isle of purbeck
2.4kW solar, 15kWh Seplos Mason, Outback power systems 3kW inverter/charger, solid fuel heating with air/air for shoulder months, 10 acres of heathland/woods.
My wife’s house: 1946 3 bed end of terrace in Somerset, ASHP with rads + UFH, triple glazed, retrofit IWI in troublesome rooms, small rear extension.
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